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Fiber in digestion: Dietary fiber: Essential for a healthy diet


Dietary fiber: Essential for a healthy diet

Eat more fiber. You’ve probably heard it before. But do you know why fiber is so good for your health?

Dietary fiber — found mainly in fruits, vegetables, whole grains and legumes — is probably best known for its ability to prevent or relieve constipation. But foods containing fiber can provide other health benefits as well, such as helping to maintain a healthy weight and lowering your risk of diabetes, heart disease and some types of cancer.

Selecting tasty foods that provide fiber isn’t difficult. Find out how much dietary fiber you need, the foods that contain it, and how to add them to meals and snacks.

What is dietary fiber?

Dietary fiber, also known as roughage or bulk, includes the parts of plant foods your body can’t digest or absorb. Unlike other food components, such as fats, proteins or carbohydrates — which your body breaks down and absorbs — fiber isn’t digested by your body. Instead, it passes relatively intact through your stomach, small intestine and colon and out of your body.

Fiber is commonly classified as soluble, which dissolves in water, or insoluble, which doesn’t dissolve.

  • Soluble fiber. This type of fiber dissolves in water to form a gel-like material. It can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium.
  • Insoluble fiber. This type of fiber promotes the movement of material through your digestive system and increases stool bulk, so it can be of benefit to those who struggle with constipation or irregular stools. Whole-wheat flour, wheat bran, nuts, beans and vegetables, such as cauliflower, green beans and potatoes, are good sources of insoluble fiber.

The amount of soluble and insoluble fiber varies in different plant foods. To receive the greatest health benefit, eat a wide variety of high-fiber foods.

Benefits of a high-fiber diet

A high-fiber diet:

  • Normalizes bowel movements. Dietary fiber increases the weight and size of your stool and softens it. A bulky stool is easier to pass, decreasing your chance of constipation. If you have loose, watery stools, fiber may help to solidify the stool because it absorbs water and adds bulk to stool.
  • Helps maintain bowel health. A high-fiber diet may lower your risk of developing hemorrhoids and small pouches in your colon (diverticular disease). Studies have also found that a high-fiber diet likely lowers the risk of colorectal cancer. Some fiber is fermented in the colon. Researchers are looking at how this may play a role in preventing diseases of the colon.
  • Lowers cholesterol levels. Soluble fiber found in beans, oats, flaxseed and oat bran may help lower total blood cholesterol levels by lowering low-density lipoprotein, or “bad,” cholesterol levels. Studies also have shown that high-fiber foods may have other heart-health benefits, such as reducing blood pressure and inflammation.
  • Helps control blood sugar levels. In people with diabetes, fiber — particularly soluble fiber — can slow the absorption of sugar and help improve blood sugar levels. A healthy diet that includes insoluble fiber may also reduce the risk of developing type 2 diabetes.
  • Aids in achieving healthy weight. High-fiber foods tend to be more filling than low-fiber foods, so you’re likely to eat less and stay satisfied longer. And high-fiber foods tend to take longer to eat and to be less “energy dense,” which means they have fewer calories for the same volume of food.
  • Helps you live longer. Studies suggest that increasing your dietary fiber intake — especially cereal fiber — is associated with a reduced risk of dying from cardiovascular disease and all cancers.

How much fiber do you need?

The Institute of Medicine, which provides science-based advice on matters of medicine and health, gives the following daily fiber recommendations for adults:

Fiber: Daily recommendations for adults

Age 50 or younger Age 51 or older
Institute of Medicine
Men 38 grams 30 grams
Women 25 grams 21 grams

Your best fiber choices

If you aren’t getting enough fiber each day, you may need to boost your intake. Good choices include:

  • Whole-grain products
  • Fruits
  • Vegetables
  • Beans, peas and other legumes
  • Nuts and seeds

Refined or processed foods — such as canned fruits and vegetables, pulp-free juices, white breads and pastas, and non-whole-grain cereals — are lower in fiber. The grain-refining process removes the outer coat (bran) from the grain, which lowers its fiber content. Enriched foods have some of the B vitamins and iron added back after processing, but not the fiber.

Fiber supplements and fortified foods

Whole foods rather than fiber supplements are generally better. Fiber supplements — such as Metamucil, Citrucel and FiberCon — don’t provide the variety of fibers, vitamins, minerals and other beneficial nutrients that foods do.

Another way to get more fiber is to eat foods, such as cereal, granola bars, yogurt and ice cream, with fiber added. The added fiber usually is labeled as “inulin” or “chicory root.” Some people complain of gassiness after eating foods with added fiber.

However, some people may still need a fiber supplement if dietary changes aren’t sufficient or if they have certain medical conditions, such as constipation, diarrhea or irritable bowel syndrome. Check with your doctor before taking fiber supplements.

Tips for fitting in more fiber

Need ideas for adding more fiber to your meals and snacks? Try these suggestions:

  • Jump-start your day. For breakfast choose a high-fiber breakfast cereal — 5 or more grams of fiber a serving. Opt for cereals with “whole grain,” “bran” or “fiber” in the name. Or add a few tablespoons of unprocessed wheat bran to your favorite cereal.
  • Switch to whole grains. Consume at least half of all grains as whole grains. Look for breads that list whole wheat, whole-wheat flour or another whole grain as the first ingredient on the label and have at least 2 grams of dietary fiber a serving. Experiment with brown rice, wild rice, barley, whole-wheat pasta and bulgur wheat.
  • Bulk up baked goods. Substitute whole-grain flour for half or all of the white flour when baking. Try adding crushed bran cereal, unprocessed wheat bran or uncooked oatmeal to muffins, cakes and cookies.
  • Lean on legumes. Beans, peas and lentils are excellent sources of fiber. Add kidney beans to canned soup or a green salad. Or make nachos with refried black beans, lots of fresh veggies, whole-wheat tortilla chips and salsa.
  • Eat more fruit and vegetables. Fruits and vegetables are rich in fiber, as well as vitamins and minerals. Try to eat five or more servings daily.
  • Make snacks count. Fresh fruits, raw vegetables, low-fat popcorn and whole-grain crackers are all good choices. A handful of nuts or dried fruits also is a healthy, high-fiber snack — although be aware that nuts and dried fruits are high in calories.

High-fiber foods are good for your health. But adding too much fiber too quickly can promote intestinal gas, abdominal bloating and cramping. Increase fiber in your diet gradually over a few weeks. This allows the natural bacteria in your digestive system to adjust to the change.

Also, drink plenty of water. Fiber works best when it absorbs water, making your stool soft and bulky.

Jan. 06, 2021

Show references

  1. Kim Y, et al. Dietary fibre intake and mortality from cardiovascular disease and all cancers: A meta-analysis of prospective cohort studies. Archives of Cardiovascular Disease. 2016;109:39.
  2. Duyff RL. Carbs: Sugars, starches, and fiber. In: Academy of Nutrition and Dietetics Complete Food and Nutrition Guide. 5th ed. New York, N.Y.: Houghton Mifflin Harcourt; 2017.
  3. Nutrition facts label: Dietary fiber. U.S. Food and Drug Administration. https://www.accessdata.fda.gov/scripts/InteractiveNutritionFactsLabel/#intro. Accessed Oct. 1, 2018.
  4. Veronese N, et al. Dietary fiber and health outcomes: An umbrella review of systematic reviews and meta-analyses. American Journal of Clinical Nutrition. 2018;107:436.
  5. Song M, et al. Fiber intake and survival after colorectal cancer diagnosis. Journal of the American Medical Association: Oncology. 2018;41:71.
  6. Colditz GA. Healthy diet in adults. https://www.uptodate.com/contents/search. Accessed Oct. 1, 2018.
  7. Dietary reference intakes (DRIs): Recommended dietary allowances and adequate intakes, total water and macronutrients. Institute of Medicine. http://www.nap.edu/. Accessed Oct. 4, 2018.

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Why Is Fiber Important in Digestive Health?

We hear a lot about the health benefits of protein — but all too often, the pros of eating fiber go overlooked. Everyday Health reached out to 10 digestive health experts and asked them exactly how fiber boosts your digestive health (and whether it’s possible to eat too much).

Mark Babyatsky, MD, chair of the department of medicine at Mount Sinai, in New York City

Dietary fiber, found particularly in vegetables, fruits, beans, and whole grains, helps to keep bowel movements regular. Individuals who consume high-fiber diets have much lower rates of constipation than individuals that eat a low-fiber diet, plus they have fewer hemorrhoids and diverticula (outpouchings) in the colon. Too much fiber may result in loose stools, bloating, or even diarrhea.

Kenneth Brown, MD, gastroenterologist

Dietary fiber is the term used to describe the combination of both insoluble and soluble fibers. Soluble fiber is the form of fiber that dissolves in water. Examples of foods that contain soluble fiber include fruits, oats, legumes and barley. Insoluble fiber comes from plant cell walls and does not dissolve in water. Examples of foods that contain insoluble fiber include wheat, vegetables, and seeds. Fiber works by both bulking up the stool and retaining water.

In addition, bacteria help digest the fiber which produces healthy ingredients for the colon such as short chain fatty acids. Fiber can be beneficial for both diarrhea and constipation depending how much fluid is also taken in with the fiber. Fiber can actually become a constipating agent if the amount of fluid taken in is too low.

Lisa Ganjhu, DO, gastroenterologist

Fiber plays a major role in digestive health. Fiber is the fuel the colon cells use to keep them healthy. Fiber also helps to keep the digestive tract flowing, by keeping your bowel movements soft and regular.

It is possible to get too much fiber, and your body will know it. You may experience bloating and many more bowel movements than you are normally are used to.

Jo Ann Hattner, MPH, RD

Fibers are primarily non-digestible carbohydrates. Fibers are components of plant foods, fruits, vegetables, dried beans and peas, lentils, nuts, and seeds — any food that is classified as a plant. The fiber provides structure. Think of the celery stalk and the obvious vertical fiber strings that one often gets caught in their teeth. In addition, because fibers are non-digestible, they contribute to stool bulk and add form to the stool. People with irregularity are often advised to increase their fiber and fluid intake.

But can you get too much? Well yes, you can get too much of anything. But you will know when you do. When you eat too much fiber, your digestive system may be overwhelmed and you will suffer from abdominal bloating and pass excessive gas. You don’t want that, so keep an open mind and just eat as much fiber as you personally need to keep regular and enjoy a flat abdomen.

Another really important role of fiber is that some fibers are prebiotics — meaning they are fermented in the colon by the healthful beneficial bacteria. The products of this fermentation, which include short chained fatty acids, are thought to be healthful to the lining of the colon. In addition the acidic milieu that results from the fermentation is unfriendly to the survival of the pathogenic (harmful) bacteria which cause illness and may contribute to an unhealthy colonic environment. Expect more research findings on this subject.

Lisa Pichney, MD, gastroenterologist

Fiber is good for the gastrointestinal tract because it provides bulk to the stool, helping in colonic lubrication and transit. Too much fiber can result in unwanted gas production.

Seth Rosen, MD, gastroenterologist

A high-fiber diet can contribute greatly to gastrointestinal health as well as to a general healthy lifestyle. Fiber helps to regulate bowel movements so they are not too loose or too hard and may decrease the risk of diverticulosis and diverticulitis. Most high-fiber foods tend to be low in calories, sugar, and fat, so they are generally healthy. When eating high-fiber foods one may feel fuller and thereby less inclined to overeat.

Additionally, high-fiber diets are often part of a low-cholesterol, heart-healthy diet. While it is rare for most of us to exceed the recommended daily fiber intake, some people do have difficulty with gas and bloating when eating a large amount of fiber or introducing fiber too quickly into the diet. Also, keep in mind, eating fiber always requires adequate hydration and help to minimize the gas and bloating that may develop.

Sutha Sachar, MD, gastroenterologist

A diet high in fiber has repeatedly shown benefits in preventing colon cancer. Contrary to what many people think, soluble fiber can be used for treatment of diarrhea as well as constipation. The only drawback to eating “too much fiber” is that is can cause gas. This can usually be overcome by drinking plenty of water along with it.

Fiber and Digestion Problems

Suffering from diarrhea? Conventional wisdom says choose foods high in fiber. Constipated? Eat a high-fiber diet, experts suggest.

That’s right, as contradictory as it may seem, the same remedy can work for diarrhea and constipation.

“Part of the answer is that fiber helps normalize transit time, or the rate at which food moves through the digestive tract,” says Joanne L. Slavin, PhD, RD, professor of food science and nutrition at the University of Minnesota.

Fiber Regulates Digestion

Constipation happens when food moves too slowly through the large intestines, often resulting in hard stool that is difficult to pass. Eating fiber-rich foods helps move the contents of the large intestine along more quickly. Fiber also absorbs water, softening stools so that they pass more easily.

Diarrhea occurs when undigested food moves too fast, before the intestines can absorb water, resulting in loose stools. Fiber’s ability to absorb water helps make stools more solid. And by slowing transit time, fiber gives the large intestines a chance to absorb additional water. Fiber also helps bulk up the contents of the large intestines, binding indigestible food together.

“Having something left at the end of digestion and absorption turns out to be necessary to form a normal stool,” says Slavin, a leading expert on fiber and digestion.

Types of Fiber: Insoluble and Soluble Fiber

Fiber is the indigestible part of carbohydrates found mostly in plants. Recent research reveals that there are many forms of fiber, each with a unique effect on nutrition and health. Two important categories are soluble and insoluble fiber.

Soluble fiber partly dissolves in water, creating a gel-like substance that helps lower cholesterol. Sources of soluble fiber include oats, barley, rye, dried beans, oranges, and apples.

Insoluble fiber remains more intact as it passes through the digestive system. That makes insoluble fiber especially helpful in preventing or easing constipation. Insoluble fiber may also help with weight loss, by making meals seem more filling without adding calories. Sources of insoluble fiber include wheat, brown rice, celery, carrots, nuts, and seeds.

Foods can contain both soluble and insoluble fiber.

Fiber can also be distinguished on the basis of its source. Research suggests that cereal fibers have an edge in aiding digestion, as well as proving beneficial in protecting against coronary artery disease, type 2 diabetes, and metabolic syndrome.

“Cereal grains are typically higher in total fiber than fruits and vegetables, so that may explain why they stand out in research studies,” Slavin says. Cereal fiber comes from oats, wheat, barley, and other grains.

Mix and Match Fibers

Certain sources of fiber may be especially helpful for treating particular conditions. If your goal is to lower blood cholesterol levels, for instance, Slavin recommends helping yourself to lots of oats, barley, and beans, which are rich in soluble fiber. To boost levels of the friendly bacteria that inhabit the intestines and help digest food, she recommends wheat, onions, artichokes, and chicory. These foods are loaded with fructo-oligosaccharides, components in some forms of fiber that encourage the growth of these helpful bacteria.

Before we start worrying about which fibers to choose, most of us would do well to choose any form of fiber. Surveys show that the average American consumes only half the fiber needed for optimal health, including a healthy digestive system. Experts agree, the best way to keep digestion on track is to increase consumption of fiber in all its many forms. Eat a varied diet that includes whole grains, fruits, vegetables, nuts, seeds, and legumes.

What Is Fiber, and Why Is It Vital for Digestive Health?: A Path to Natural Health: Naturopathic Doctors

So far in this series on digestive health, we’ve looked at the following topics:

  1. The Basics of Irritable Bowel Syndrome (IBS)
  2. Small Intestinal Bacterial Overgrowth (SIBO)
  3. The Low-FODMAP Diet and Its Role In Treating IBS
  4. What is the Gut Biome and How Does It Affect Our Health?

Today’s topic in this series is FIBER. You’ve probably heard that fiber is important for digestion. For example, most doctors will tell you a high-fiber diet is necessary to prevent constipation. Yet, when some people increase their fiber intake, they can actually get MORE constipated, or they can experience stomach pain, bloating, or even diarrhea.

It seems baffling: if fiber is good for our digestion, how can it cause digestive problems? The truth is that fiber is a more complicated subject than most people realize. That’s why in this article, we’ll be looking at what fiber is, what it does, the different types of fiber, and how to eat the right type of fiber, so you can keep your digestive system healthy and reap all the wonderful benefits fiber offers.

What Is Fiber?

Fiber (also known as roughage or bulk) is the indigestible part of plants. It is different from fats, proteins, and carbohydrates, which are broken down by the body and absorbed into our blood stream. Instead, fiber passes through the stomach, small intestine, large intestine, and out of the body in almost the same form it took when you ate it.

What Are the Different Types of Fiber?

Fiber is classified into two categories: soluble and insoluble. Soluble fiber dissolves in water, taking on a gooey, gel-like consistency. Insoluble fiber absorbs water, and helps add bulk in the intestines. Most plant-based foods contain both soluble and insoluble fiber.

12 Amazing Health Benefits of Fiber

Both kinds of fiber work together to keep the digestive system healthy and to help prevent disease. While soluble and insoluble fiber each play a specific role in your digestive health, there is some overlap in the benefits they provide. Here’s just a short list of some of the impressive things fiber can do for you:

  1. Maintain regular bowel function – The bulking properties of insoluble fiber, and the gelatinous quality of soluble fiber, make it easier for stool to travel through the colon. This helps reduce the likelihood of constipation. Insoluble fiber also helps reduce diarrhea by holding onto water in the gut.
  2. Keep your “gut biome” healthy (see my previous article about the gut biome) – Bacteria in our gut feast on the fiber that comes from our diet. Fiber nourishes them and helps them to flourish so they can aid us in digestion and nutrient absorption.
  3. Prevent diverticulosis and diverticulitis – Diverticulosis is when the wall of your colon becomes stretched out. Over time, diverticulosis can develop into a more serious (and extremely painful) condition called diverticulitis. Consuming fiber on a regular basis helps keep the colon muscles toned, making them less likely to stretch out.
  4. Lower “bad” cholesterol – In its gel-like form, soluble fiber can bind to LDL cholesterol (the bad kind) and help eliminate it from your body.
  5. Stabilize blood sugar – Fiber helps slow down the absorption of sugar in the bloodstream, thus keeping glucose levels from going too high.
  6. Prevent type-2 diabetes – By reducing LDL cholesterol and helping you maintain healthy blood sugar levels, fiber reduces your risk of developing type-2 diabetes.
  7. Lower high blood pressure – According to a 2005 report published in the Journal of Hypertension, multiple studies have indicated that adding fiber to the diet can help lower high blood pressure.1
  8. Lower the risk of developing hemorrhoids – As constipation is a common cause of hemorrhoids, a high-fiber diet helps prevent them from developing.
  9. Reduce inflammation – Bad (or “pathogenic”) bacteria can lead to inflammation and diseases of the colon. Fiber helps keep good bacteria healthy and reduces the damage caused by bad bacteria.
  10. Help you maintain healthy weight – Fiber-rich foods are bulky, making us feel fuller faster. They also make us feel fuller longer because they take longer to digest than other foods. This combination can help keep us from overeating or snacking between meals. Fiber-rich foods also tend to be lower in calories than fats or proteins.
  11. Help with detoxification – Some toxins can enter our bodies via our food or environment. Others (such as excess hormones) can develop as byproducts of metabolism. Fiber binds to these toxins and helps our digestive system eliminate them from our bodies, so we are less likely to suffer their harmful effects.
  12. Lower the risk of developing colon cancer – Chronic constipation can lead to the development of polyps in the colon, which is one of the risk factors for developing colon cancer. As it helps prevent constipation, adequate dietary fiber lowers the risk of polyps from developing.

Is There Such a Thing as the WRONG Kind of Fiber?

At the beginning of this article, I mentioned that rather than feeling better when they increase their fiber intake, some people can actually feel worse. This unfortunate experience most frequently occurs in patients who struggle with irritable bowel syndrome (IBS) or small intestinal bacterial overgrowth (SIBO). Let me explain how this can happen.

Most varieties of soluble fiber can become fermented by gut bacteria. We call these fermentable foods “FODMAPs”. People with IBS or SIBO are especially sensitive to fermentation in the gut, which will create gas, bloating, and abdominal pain. Other people suffer from an overgrowth of yeast in the large intestine. As yeast thrives on fermented substances in the intestines, consuming soluble fiber is likely to make them feel much worse.

Thus, if you have any of these conditions, it’s NOT a good idea to increase your intake of fibers classed as “FODMAPs” until you have addressed the underlying problem and your digestive issues have stabilized. You can find a list of high- and low-FODMAP foods in my previous article “The Low-FODMAP Diet and Its Role In Treating IBS”.

Once you’ve reestablished the correct micro-ecology in your gut, you should be able to resume a diet containing all varieties of healthy fiber.

How Much Fiber Should You Eat a Day?

While the optimum amount of fiber you need per day will depend upon your individual health, a basic guideline for your minimum daily requirement is:

Men Age 50 or younger: 38 grams

Men Age 51 or older: 30 grams

Women Age 50 or younger: 25 grams

Women Age 51 or younger: 21 grams

Which Foods Are High in Fiber?

Soluble fiber is found in varying quantities in all plant foods, including (but not limited to):

  • Legumes: split peas and lentils
  • Beans: lima, navy, soy, black, chickpeas, kidney
  • Grains: oats, rye, and barley
  • Fruits: figs, avocados, plums, prunes, berries, ripe bananas, and the skin of apples and pears
  • Vegetables: broccoli, Brussel sprouts, collard greens, carrots, and Jerusalem artichokes
  • Root vegetables and tubers: sweet potatoes and onions
  • Nuts: almonds, peanuts, soy nuts
  • Seeds: flax, chia, sunflower
  • Psyllium seed husks

Sources of insoluble fiber include (but are not limited to) the following. You’ll notice that many foods contain BOTH soluble and insoluble fiber:

  • Whole grain foods (unrefined)
  • Bran: wheat and corn
  • Legumes: beans and peas
  • Nuts and seeds (all kinds)
  • Potato skins
  • Lignans: found abundantly in flaxseeds, as well as in sesame seeds, berries, and other foods)
  • Vegetables: green beans, cauliflower, zucchini, celery
  • Fruits: avocado, unripe bananas, grape skins, tomato skins

NOTE: Refined grains have had their outer shells removed and are lower in fiber. Sometimes the outer part of the grain (the “bran”) is added back into foods to increase their fiber content (oat bran is one example). Processed foods, canned fruits and vegetables, and pulp-free juice are also lower in fiber.

Top 15 High-Fiber Foods

To get an idea of what should be a part of your diet to ensure you are getting enough fiber, here’s a list of my top 15 favorites, plus suggested portion sizes:

  1. Raspberries: 1 cup = 8 gm.
  2. Strawberries: 1 cup = 3.0 gm.
  3. Apple: 1 medium with skin = 4.4 gm.
  4. Pear: 1 medium with skin = 5.5 gm.
  5. Lentils: 1 cup = 15.6 gm.
  6. Black beans: 1 cup = 15 gm.
  7. Almonds: 1 oz. (23 nuts with skin) = 3.5 gm.
  8. Peas: 1 cup = 8.8 gm.
  9. Broccoli: 1 cup = 5.1 gm.
  10. Oatmeal: 3.5 ounces = 10 gm.
  11. Barley (pearled): 1 cup = 6.0 gm.
  12. Whole wheat spaghetti: 1 cup = 6.3 gm.
  13. Bran flakes: ¾ cup = 5.5 gm.
  14. Chia seeds: 1 TB = 5 gm.
  15. Popcorn: 3 cups = 3.6 gm.

Should I Take a Fiber Supplement?

Most people get enough fiber through their normal diet. But if you feel you need an extra boost, I recommend adding ground flax or chia seeds to smoothies or protein shakes. Their soluble properties also help add bulk to the mixture, so you feel satiated for longer.

If your lifestyle causes you to fall short of your targeted dietary fiber requirements, you could add a fiber supplement to your daily diet. For example, people who travel for work often have erratic dietary habits, and may be prone to bouts of constipation. Taking a fiber supplement can help keep them regular when on the road.

There are so many “fiber boosting” products on the market: powders, drinks, fiber bars, and fiber cereals. Insulin or chicory root are common ingredients in such products. Which product to choose is really a matter of convenience, taste, and ingredients (especially if you have food allergies or sensitivities).

IMPORTANT: Some people (even those without IBS or SIBO) will complain of gas and intestinal discomfort after eating foods with added fiber, especially if they are unaccustomed to it. Start with a small serving, and gradually work your way up over a period of a few weeks, until your body adjusts to the change. It is also important to drink more water when you increase your fiber to help it move more easily through your system, and to unlock many of its health properties.

If you still experience digestive distress from fiber after a few weeks, you may need to be evaluated for SIOB, and discuss going on a low-FODMAP diet, with your practitioner.

Closing Thoughts

As we’ve explored in this article, a diet rich in plant-based fiber keeps our digestive tract healthy, decreases our cholesterol, stabilizes our blood sugar, decreases our risk of colon cancer, and helps us maintain a healthy weight – to name just a few benefits. Unfortunately, the standard America diet tends to be low in fiber and high in processed refined foods, putting many people at risk of disease and overall poor health. That’s why I hope this article has inspired (and informed) you to include adequate fiber in your daily diet.

If you or someone you know suffers with dietary or digestive problems, I invite you to drop me a line on the “contact us” page on this site and request a free initial consultation to discuss your needs.  I treat patients locally at my practice in Issaquah, Washington, and worldwide via phone or Skype.

Next time, we’ll look at the role of the gallbladder and the important part it plays in our digestive health. I hope you’ll subscribe to this blog so you can receive that article and all future articles on A Path to Natural Health.

“Health is a journey we travel over our lifetime.
Learn everything you can to make your journey a happier one.”


Fiber | The Nutrition Source

Fiber is a type of carbohydrate that the body can’t digest. Though most carbohydrates are broken down into sugar molecules, fiber cannot be broken down into sugar molecules, and instead it passes through the body undigested. Fiber helps regulate the body’s use of sugars, helping to keep hunger and blood sugar in check.

Children and adults need at least 20 to 30 grams of fiber per day for good health, but most Americans get only about 15 grams a day. Great sources are whole fruits and vegetables, whole grains, and beans.

Fiber comes in two varieties, both beneficial to health:

  • Soluble fiber, which dissolves in water, can help lower glucose levels as well as help lower blood cholesterol. Foods with soluble fiber include oatmeal, nuts, beans, lentils, apples and blueberries.
  • Insoluble fiber, which does not dissolve in water, can help food move through your digestive system, promoting regularity and helping prevent constipation. Foods with insoluble fibers include wheat, whole wheat bread, whole grain couscous, brown rice, legumes, carrots, cucumbers and tomatoes.

The best sources of fiber are whole grains, fresh fruits and vegetables, legumes, and nuts.

Some tips for increasing fiber intake:

  • Eat whole fruits instead of drinking fruit juices.
  • Replace white rice, bread, and pasta with brown rice and whole grain products.
  • For breakfast, choose cereals that have a whole grain as their first ingredient.
  • Snack on raw vegetables instead of chips, crackers, or chocolate bars.
  • Substitute beans or legumes for meat two to three times per week in chili and soups.

Fiber and disease

Fiber appears to reduce the risk of developing various conditions, including heart disease, diabetes, diverticular disease, and constipation. Despite these benefits, fiber probably has little, if any, effect on colon cancer risk.

Heart disease

High intake of dietary fiber has been linked to a lower risk of heart disease in a number of large studies that followed people for many years. (16) In a Harvard study of over 40,000 male health professionals, researchers found that a high total dietary fiber intake was linked to a 40 percent lower risk of coronary heart disease. (17) A related Harvard study of female nurses produced quite similar findings. (18)

Higher fiber intake has also been linked to a lower risk of metabolic syndrome, a combination of factors that increases the risk of developing heart disease and diabetes. These factors include high blood pressure, high insulin levels, excess weight (especially around the abdomen), high levels of triglycerides, and low levels of HDL (good) cholesterol. Several studies suggest that higher intake of fiber may offer protective benefits from this syndrome. (19,20)

Type 2 diabetes

Diets low in fiber and high in foods that cause sudden increases in blood sugar may increase the risk of developing type 2 Diabetes. Both Harvard studies—of female nurses and of male health professionals—found that this type of diet more than doubled the risk of type 2 diabetes when compared to a diet high in cereal fiber and low in high-glycemic-index foods. (21-23) A diet high in cereal fiber was linked to a lower risk of type 2 diabetes.

Other studies, such as the Black Women’s Health Study (24) and the European Prospective Investigation Into Cancer and Nutrition–Potsdam, have shown similar results.

Read about what you can do to help prevent type 2 diabetes.

Diverticular disease

Diverticulitis, an inflammation of the intestine, is one of the most common age-related disorders of the colon in Western society. Among male health professionals in a long-term follow-up study, eating dietary fiber, particularly insoluble fiber, was associated with about a 40 percent lower risk of diverticular disease. (25)

Fiber and constipation

Constipation is the most common gastrointestinal complaint in the United States, and consumption of fiber seems to relieve and prevent constipation.

The fiber in wheat bran and oat bran is considered more effective than fiber from fruits and vegetables. Experts recommend increasing fiber intake gradually rather than suddenly, and because fiber absorbs water, beverage intake should be increased as fiber intake increases.

Colon cancer

Studies have largely failed to show a link between fiber and colon cancer. One of these—a Harvard study that followed over 80,000 female nurses for 16 years—found that dietary fiber was not strongly associated with a reduced risk for either colon cancer or polyps (a precursor to colon cancer). (26)

Following the Scientific Trail: The Story on Fiber and Colon Cancer

Because science is such a dynamic process, you can never exactly tell where it is going to lead you. Conclusions that once seemed logical and fairly solid may be revised—or completely overturned—as more and better research is done on a particular topic. One example of this is the relationship between fiber and colon cancer.

Starting about 30 years ago, a high fiber intake was regularly recommended as one way to lower the risk for colon cancer. This recommendation was largely based on observations that countries with a high fiber intake tended to have rates of colon cancer lower than the rates found in countries with a low fiber intake.

But such descriptive studies don’t provide the most definitive information. While they are often good points to start a scientific journey, they only take a broad look at large groups of people. Descriptive studies generally can’t address all of the factors that might account for differences in rates of disease. Fiber intake could indeed have something to do with the differences in colon cancer rates, but those differences could also involve many other things that differ between countries, including other diet or lifestyle factors.

When studies that can take such things into account on an individual level began to look at the issue of fiber and colon cancer, the picture became much less clear. A number of case-control studies found that a high fiber intake was linked to a lower risk of colon cancer, but many did not. Given these wavering results—and because case-control studies are not an optimal way to assess food intake, relying as they do on participants’ recollections of what they ate in the past—more research using better methods was needed. In the meantime, many health professionals still regularly recommended a high fiber intake for people trying to lower their risk of colon cancer.

Not until the results of cohort studies came out did this recommendation begin to lose its backing. Because cohort studies observe a group of people over time, their findings are generally stronger than those of case-control studies, especially when it comes to something like diet and colon cancer. What most of these cohort studies found was that fiber intake had very little, if any, link with colon cancer.

Such findings were further bolstered by the results of randomized trials—types of studies that many consider the gold-standard of research. These studies took a group of people and randomly assigned individuals to one of two groups. One group was put on a high fiber diet, while the other group followed a lower fiber diet. After 3 to 4 years, the two groups were compared and no difference was found in rates of colon polyps—noncancerous growths that can turn into cancer. Of course, colon polyps are not cancer, but since it’s thought that all colon cancers start as polyps, it is strong evidence that fiber intake has no direct link with colon cancer.

In this case, the path of discovery led from widespread belief in a clear link between fiber and colon cancer to acceptance of the likelihood that there was no strong link between the two. As such, it’s an excellent example of how research can often develop. What may start as a clear connection based on findings from broad, descriptive studies can slowly unravel as more and better-quality research unveils the true nature of a relationship. However, keep in mind that a weak relationship is difficult to exclude altogether. Further studies might yet demonstrate a weak effect of fiber on colon cancer, although such a finding wouldn’t alter the conclusion that other means must be sought to prevent colon cancer.

Breast cancer

A large-scale 2016 study (27) led by researchers at Harvard T.H. Chan School of Public Health showed findings that higher fiber intake reduces breast cancer risk, suggesting that fiber intake during adolescence and early adulthood may be particularly important.

  • Women who eat more high-fiber foods during adolescence and young adulthood, including vegetables and fruit, may have significantly lower breast cancer risk than those who eat less dietary fiber when young.


16. Pereira MA, O’Reilly E, Augustsson K, et al. Dietary fiber and risk of coronary heart disease: a pooled analysis of cohort studies. Arch Intern Med. 2004;164:370-6.

17. Rimm EB, Ascherio A, Giovannucci E, Spiegelman D, Stampfer MJ, Willett WC. Vegetable, fruit, and cereal fiber intake and risk of coronary heart disease among men. JAMA. 1996;275:447-51.

18. Brown L, Rosner B, Willett WW, Sacks FM. Cholesterol-lowering effects of dietary fiber: a meta-analysis. Am J Clin Nutr. 1999;69:30-42.

19. McKeown NM, Meigs JB, Liu S, Wilson PW, Jacques PF. Whole-grain intake is favorably associated with metabolic risk factors for type 2 diabetes and cardiovascular disease in the Framingham Offspring Study. Am J Clin Nutr. 2002;76:390-8.

20. McKeown NM, Meigs JB, Liu S, Saltzman E, Wilson PW, Jacques PF. Carbohydrate nutrition, insulin resistance, and the prevalence of the metabolic syndrome in the Framingham Offspring Cohort. Diabetes Care. 2004;27:538-46.

21. Fung TT, Hu FB, Pereira MA, et al. Whole-grain intake and the risk of type 2 diabetes: a prospective study in men. Am J Clin Nutr. 2002;76:535-40.

22. Liu S, Willett WC, Stampfer MJ, et al. A prospective study of dietary glycemic load, carbohydrate intake, and risk of coronary heart disease in US women. Am J Clin Nutr. 2000;71:1455-61.

23. Schulze MB, Liu S, Rimm EB, Manson JE, Willett WC, Hu FB. Glycemic index, glycemic load, and dietary fiber intake and incidence of type 2 diabetes in younger and middle-aged women. Am J Clin Nutr. 2004;80:348-56.

24. Krishnan S, Rosenberg L, Singer M, et al. Glycemic index, glycemic load, and cereal fiber intake and risk of type 2 diabetes in US black women. Arch Intern Med. 2007;167:2304-9.

25. Aldoori WH, Giovannucci EL, Rockett HR, Sampson L, Rimm EB, Willett WC. A prospective study of dietary fiber types and symptomatic diverticular disease in men. J Nutr. 1998;128:714-9.

26. Fuchs CS, Giovannucci EL, Colditz GA, et al. Dietary fiber and the risk of colorectal cancer and adenoma in women. N Engl J Med. 1999;340:169-76.

27. Farvid MS, Eliassen AH, Cho E, Liao X, Chen WY, Willett WC. Dietary fiber intake in young adults and breast cancer risk. Pediatrics 2016: 137(3).

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Soluble and insoluble fiber: Differences and benefits

Dietary fiber, the indigestible part of plant material, is made up of two main types. Soluble fiber easily dissolves in water and is broken down into a gel-like substance in the part of the gut known as the colon. Insoluble fiber does not dissolve in water and is left intact as food moves through the gastrointestinal tract.

The term fiber refers to all the parts of plant-based foods that cannot be digested or absorbed by the body. Unlike simple carbohydrates, including most breads and sugars, fiber is a complex carbohydrate and does not raise blood sugar levels.

Fiber is commonly found in vegetables, fruits, whole grains, and legumes. It is also sometimes called roughage or bulk. It is an essential nutrient, which means it must be eaten in the diet.

Fast facts on soluble and insoluble fiber:

  • Soluble and insoluble are the two main types of fiber. Many fiber-rich foods contain some of both.
  • Both forms of fiber have health benefits.
  • Humans have been using fiber as a dietary aid since ancient times.
  • In a society built on refined carbohydrates, or white breads, pastas, and sugar sweeteners, getting enough fiber can take effort.

Share on PinterestWhole grains and cereals are a good source of fiber, particularly insoluble fiber.

Soluble fiber dissolves in water and gastrointestinal fluids when it enters the stomach and intestines. It is transformed into a gel-like substance, which is digested by bacteria in the large intestine, releasing gases and a few calories.

Insoluble fiber does not dissolve in water or gastrointestinal fluids and remains more or less unchanged as it moves through the digestive tract. Because it is not digested at all, insoluble fiber is not a source of calories.

The health benefits of dietary fiber are plentiful. Some of the main ones are listed here.

Soluble fiber

  • Lowering fat absorption and helping weight management: As a thick, spread-out gel, soluble fiber blocks fats that would otherwise be digested and absorbed.
  • Lowering cholesterol: Soluble fiber prevents some dietary cholesterol from being broken down and digested. Over time, soluble fiber can help lower cholesterol levels or the amount of free cholesterol in the blood.
  • Stabilizing blood sugar (glucose) levels: Just as it prevents fats from being absorbed, soluble fiber slows down the digestion rate of other nutrients, including carbohydrates. This means meals containing soluble fiber are less likely to cause sharp spikes in blood sugar levels and may prevent them.
  • Reducing the risk of cardiovascular disease: By lowering cholesterol levels, stabilizing blood sugars, and decreasing fat absorption, regularly eating soluble fiber may reduce the risk of heart disease and circulatory conditions.
  • Feeding healthy gut bacteria: Some soluble fiber-rich foods feed gut bacteria, as it is fermentable in the colon, and so it helps the bacteria thrive longer.

Insoluble fiber

  • Preventing constipation: As an indigestible material, insoluble fiber sits in the gastrointestinal tract, absorbing fluid and sticking to other byproducts of digestion that are ready to be formed into the stool. Its presence speeds up the movement and processing of waste, helping prevent gastrointestinal blockage and constipation or reduced bowel movements.
  • Lowering the risk of diverticular disease: By preventing constipation and intestinal blockages, insoluble fiber helps reduce the risk of developing small folds and hemorrhoids in the colon. It may also reduce the risk of colorectal cancer.

Soluble and insoluble fiber

  • Feeling satiated or full longer after meals: Soluble fiber slows down how quickly foods are digested, meaning most people feel full longer after fiber-rich meals. Insoluble fiber physically fills up space in the stomach and intestines, furthering the sensation of being full. These properties can help people manage their weight.
  • Helping lower disease risk: Due to fiber’s many health benefits, a high-fiber diet is associated with a lower risk of many diseases, including obesity, cardiovascular disease, diabetes, metabolic syndrome and others.

Good sources of fiber

Share on PinterestRegularly consuming good sources of fiber may help to stabilize cholesterol, blood sugar, and fat levels.

The nutrition label on food packaging lists the amount of dietary fiber found in each serving of the product.

If a product is marketed as being high in fiber or having associated health benefits, the amount of soluble and insoluble fiber in grams (g) per serving must be listed under the dietary fiber heading. Some manufacturers may also voluntarily give the soluble and insoluble content of the fiber element of the product.

According to the FDA, foods that are considered high in fiber contain at least 20 percent of the recommended daily value (DV) of dietary fiber per serving. Foods that have 5 percent or less are considered poor sources of dietary fiber.

Beans, peas, and whole grains are high in fiber. Some fruits and vegetables are also relatively high in fiber. Common foods that are good sources of fiber include:

  • cooked navy beans (1/2 cup contains 9.5 g)
  • 100 percent ready-to-eat bran (1/2 cup contains 8.8 g)
  • canned kidney beans (1/2 cup contains 8.2 g)
  • cooked split peas (1/2 cup contains 8.1 g)
  • cooked lentils (1/2 cup contains 7.8 g)
  • cooked pinto/black beans (1/2 cup contains 7. 8/7.5 g)
  • cooked artichoke (one whole artichoke contains 6.5 g)
  • cooked white beans/chickpeas/great northern beans (1/2 cup contains 6.3-6.2 g)
  • mature soybeans (1/2 cup cooked contains 5.2 g)
  • plain rye wafers or crackers (2 crackers contain 5.0 g)
  • baked sweet potato with the peel (1 medium potato contains 4.8 g)
  • raw pear or Asian pear (1 small pear contains 4.3-4.4 g)
  • cooked green peas (1/2 cup contains 4.4 g)
  • whole wheat English muffin/bread (1 muffin or 2 slices contains 4.4 g)
  • cooked bulgur wheat (1/2 cup contains 4.1 g)
  • raw raspberries (1/2 cup contains 4.0 g)
  • boiled sweet potato without the peel (1 medium potato contains 3.9 g)
  • baked potato with the peel (1 medium potato contains 3.8 g)
  • stewed prunes (1/2 cup contains 3.8 g)
  • dried figs or dates (1/2 cup contains 3.7-3.8 g)
  • raw oat bran (1/2 cup contains 3.6 g)
  • canned pumpkin (1/2 cup contains 3.6 g)
  • cooked spinach (1/2 cup contains 3.5 g)
  • shredded ready-to-eat wheat cereals (1 ounce contains 2.8-3.4 g)
  • raw almonds (1 oz. contains 3.3 g)
  • raw apple with the skin (1 medium apple includes 3.3 g)
  • cooked whole wheat spaghetti (1/2 cup contains 3.1 g)
  • raw banana or orange (1 fruit contains 3.1 g)

A healthful diet contains a mix of both soluble and insoluble fiber. Soluble fibers are more common in foods, such as beans, peas, oats, barley, apples and citrus fruits. Good sources of insoluble fiber include beans, whole wheat or bran products, green beans, potatoes, cauliflowers, and nuts.

While many fiber supplements exist, most do not contain the additional vitamins and minerals, including vitamin B and iron, found in fiber-rich foods. Supplements may also not be, as easily or fully absorbed by the body.

Share on PinterestChoosing foods rich in fiber is preferable to relying on supplements. Choosing whole grains and brown rice or pasta is also a good way to increase fiber intake.

It is helpful to keep some simple rules in mind when shopping or preparing meals. Good tips for increasing fiber intake include:

  • Picking products that have whole grains close to the start of their ingredients list.
  • Choosing foods naturally rich in fiber over supplements, such as Metamucil, Citrucel, and others.
  • Eating beans, peas, or lentils on a daily basis.
  • Eating at least one food daily that contains 20 percent DV per serving.
  • Consuming fruits and vegetables with their skins or peels intact when possible.
  • Looking up the best way to eat specific foods. The amount of dietary fiber in many foods changes, depending on whether they are raw, cooked, stewed, steamed, fried or baked.
  • Picking unrefined grain and cereal products to include regularly in a diet.
  • Picking whole fruits and vegetables rather than juices.
  • Adding beans, peas, and lentils to soups and salads
  • Adding more beans, peas, or lentils than meat, or making them the main ingredient when preparing pasta dishes, casseroles, or stir-fry.
  • Making dips or spreads out of chickpeas, beans, peas, lentils, and other pulses.
  • Eating unsalted nuts, seeds, or dried fruits as snacks, or sprinkling them over cereals, salads, or yogurt.
  • Starting the day with whole grain breakfast options, especially 100 percent ready-to-eat bran.
  • Picking brown rice above the white variety.

Why do we need it?

Dietary fiber, also known as roughage, is the indigestible part of plant foods. Fiber has a host of health benefits, including reducing the risk of heart disease and type 2 diabetes.

Fiber is mostly in vegetables, fruits, whole grains, and legumes. There are two types of fiber — soluble and insoluble — and both play important roles in health:

  • Insoluble fiber does not dissolve in water and adds bulk to the stool, preventing constipation.
  • Soluble fiber absorbs water, forming a gel-like substance in the digestive system. Soluble fiber may help lower cholesterol levels and help regulate blood sugar levels.

This article looks at the different types of fiber, why they are important, and suggests some healthful fiber-rich foods.

Dietary fiber is an essential part of a healthful diet. It is crucial for keeping the gut healthy and reducing the risk of chronic health conditions.

Most people in the United States do not get enough fiber from their diets. According to some estimates, only 5% of the population meet the adequate intake recommendations. This means that most people in the U.S. could get health benefits from increasing their daily fiber intake.

Eating fiber has many health benefits:

Protection against heart disease

Several studies over the past several decades have examined dietary fiber’s effect on heart health, including preventing cardiovascular disease and reducing blood pressure.

A 2017 review of studies found that people eating high fiber diets had significantly reduced risk of cardiovascular disease and lower mortality from these conditions.

The authors say that these heart protective effects could be because fiber reduces total cholesterol and low-density lipoprotein (LDL) cholesterol, also called ‘bad cholesterol,’ which is a major risk for heart conditions.

Better gut health

Fiber is important for keeping the gut healthy. Eating enough fiber can prevent or relieve constipation, helping waste to move smoothly through the body. It also encourages healthy gut microbiota.

According to a 2015 review, dietary fiber increases the bulk of stool, helps promote regular bowel movements, and reduces the time that waste spends inside the intestines.

According to a 2009 review, dietary fiber has a positive impact on gastrointestinal disorders, including:

  • colorectal ulcer
  • hiatal hernias
  • gastroesophageal reflux disease
  • diverticular disease
  • hemorrhoids

A 2019 review reports that fiber intake may reduce a person’s risk of colorectal cancer.

Reduced diabetes risk

Adding more fiber to the diet may also have benefits for diabetes. Fiber can help slow down the body’s absorption of sugar, helping to prevent blood sugar spikes after meals.

A 2018 review reports that people who ate high fiber diets, especially cereal fiber, had a lower risk of developing type 2 diabetes. These individuals also reported a small reduction in blood glucose levels.

Weight management

For people aiming to lose weight, a diet high in dietary fiber can help regulate weight loss. High fiber foods help a person feel fuller for longer and may help people adhere to a diet.

In a 2019 study, researchers concluded that people who increased their dietary fiber intake increased their weight loss and adherence to their dietary caloric restriction.

Fiber includes nonstarch polysaccharides, such as cellulose, dextrins, inulin, lignin, chitins, pectins, beta-glucans, waxes, and oligosaccharides.

Soluble and insoluble are the two types of dietary fiber.

Most high fiber containing foods have both insoluble and soluble fiber, so people do not need to think much about the difference. Instead, they can focus on overall fiber intake.

Soluble fiber

Soluble fiber dissolves in water and forms a gel-like substance in the stomach. Bacteria later break the gel down in the large intestine. Soluble fiber provides some calories to the individual.

Soluble fiber provides the following benefits:

  • lowering LDL cholesterol in the blood by affecting how the body absorbs dietary fat and cholesterol
  • slowing absorption of other carbohydrates through digestion, which can help regulate blood sugar levels

Good sources of soluble fiber include:

  • beans
  • fruits
  • oats
  • nuts
  • vegetables

Insoluble fiber

Insoluble fiber does not dissolve in water and passes through the gastrointestinal tract, mostly intact. It does not provide calories.

Insoluble fiber helps build bulk in the stool, helping a person pass stool more quickly. It can also help prevent constipation.

Good sources of insoluble fiber include:

  • fruits
  • nuts
  • vegetables
  • whole grain foods

For more science-backed resources on nutrition, visit our dedicated hub.

According to the Academy of Nutrition and Dietetics, the recommended intake for dietary fiber in a 2,000 calorie diet is:

  • 25 grams (g) per day for adult females
  • 38 g per day for adult males

People need less fiber after 50 years of age at around 21 g for women and 30 g for men. During pregnancy or breastfeeding, women should aim for at least 28 g per day.

Learn more about daily fiber recommendations.

People who are allergic to high fiber foods can find it difficult to get enough fiber. They should speak to their doctor about finding sources of fiber that will not cause an allergic reaction.

In some cases, a person may want to talk to their doctor about fiber supplements. A doctor may recommend these if the individual has constipation or trouble passing stool. Pharmacies sell fiber supplements, such as Metamucil, Citrucel, and FiberCon.

These products do not provide the same levels of vitamins and nutrients as natural, high fiber foods, but they are beneficial when someone cannot get enough fiber from their diet.

People can boost their daily fiber intake by making a variety of small changes:

  • eat fruits and vegetables with the skins on, as the skins contain lots of fiber
  • add beans or lentils to salads, soups, and side dishes
  • replace white breads and pastas for whole wheat versions
  • aim to eat 4.5 cups of vegetables and 4.5 cups of fruit each day, as the American Heart Association suggest
  • if unable to meet the daily requirements, consider using fiber supplements

Dietary fiber is an essential component of a healthful diet, with research linking a high fiber diet with reduced risks of many health conditions, including cardiovascular disease, type 2 diabetes, and certain cancers. Fiber is also important for keeping the gut healthy.

Most people in America do not meet their adequate daily requirement of fiber. People can increase this measure by eating more high fiber foods, fruits and vegetables with the skins on, or by taking fiber supplements if this is not possible.

90,000 in what products does it contain, how to use it?

Fiber is food components that are not digested by digestive enzymes, but processed by the beneficial intestinal microflora. It is important for the body that in the daily diet there are foods containing it in sufficient quantities.

It has the following beneficial properties:

  • helps to eliminate cholesterol;
  • saturates well, preventing overeating;
  • improves intestinal motility;
  • reduces the rate of formation of fatty deposits;
  • removes carcinogens, reducing the risk of developing oncology;
  • has a mild diuretic effect, helping to eliminate excess fluid and sodium from the body.

Attention! A diet rich in dietary fiber is indicated for the prevention and treatment of obesity, dysbiosis, diabetes mellitus, atherosclerosis, hemorrhoids, liver and gallbladder diseases.

Where is it contained and what is the composition?

Dietary fiber consists of polysaccharides (cellulose, pectin, gum, hemicellulose) and lignin. The largest amount of fiber is found in bran. They contain a lot of B vitamins, as well as mineral salts of potassium, magnesium, phosphorus and iron.In particular, the content of this trace element in wheat bran is 2 times higher than in potatoes.

Attention! Fiber is completely absent in premium flour, sugar and sour cream.

It is present in significant quantities in some cereals, dried mushrooms, raw vegetables, fruits, dried apricots, dates. The substance is not assimilated by the body, therefore it does not give it energy. Fiber makes you feel full faster and stays in the stomach longer than other foods.

Thanks to fiber, eating one serving of whole grain bread can be as full as one serving of white bread. Plus, foods with fiber are beneficial in that it helps accelerate the elimination of fat from the digestive system.

How much fiber do you need per day?

A healthy adult needs to consume 15–25 grams of fiber per day, which enters the body with vegetables and fruits. It is also found in legumes, brown rice and whole grains. It is not found in meat and dairy products.

Attention! When eating food rich in dietary fiber, you need to increase the amount of fluid you drink by 0.5-1 liter. Otherwise, you may experience constipation.

In chronic inflammation of the pancreas and intestines, the amount of dietary fiber consumed should gradually increase over 10-14 days.

However, one should not get carried away. With the use of a significant amount of fiber for a long time, it is possible that a deficiency of fat-soluble vitamins and microelements occurs. To prevent this, multivitamin complexes with trace elements should be taken as a preventive measure.


These substances, interacting with water, swell and absorb cholesterol present in the intestines. They remove toxins and harmful microflora from the body. These abilities are enhanced by the presence of malic and citric acids found in fruits, berries and citrus fruits.

Pectins are especially useful for diseases of the digestive system. They normalize the intestinal microflora and cholesterol levels, cleanse the body, preventing its intoxication. Most of these substances are found in beets, black currants, apples, peaches and oranges. They are found in cabbage and carrots, as well as in the juice of mature fruits and vegetables.

Attention! To stabilize the balance between “good” and “bad” cholesterol, it is recommended to eat one grapefruit every day, as it contains a lot of pectin.

Food rich in fiber prevents the development of heart and vascular diseases, diabetes, cholelithiasis, obesity and stomach cancer. To prevent such problems, it is enough to eat an apple every day, a portion of red borscht or buckwheat porridge, a handful of nuts, or drink fresh juices and make cabbage salads.

90,000 Fiber. What is it, why is it needed, why and how is there more than

The World Health Organization recommends eating 400 grams (5 servings) of fruits and vegetables per day, which contains 25-30 grams of fiber.

According to statistics, Europeans consume only 50–70% of the daily value of fiber. This is especially influenced by the predominance of fast food, convenience foods, saturated fats, sugar and animal protein in the diet.

In 2019, a group of scientists conducted a meta-analysis of the effect of fiber on the human body.The results of the study confirmed that the daily fiber intake of 25-30 grams, which is recommended by the WHO, is optimal for health.

In this article we will talk about what fiber is, which foods contain it and how it affects the body.


1. What is fiber
2. How fiber supports the health of the microbiota
3. How to increase the proportion of fiber in the diet
4. How to assess the health of the microbiota

What is fiber

Fiber is a complex carbohydrate or dietary fiber found in plant foods.It is not digested by the body, but bacteria in the gut use it for a number of functions.

There are two types of fiber – soluble and insoluble. Almost all plants contain both species, but in different proportions. Both are needed by our body.

Soluble fiber

Photo by Melissa Di Rocco / Unsplash

Soluble fiber, when combined with water, acquires a viscous gel-like consistency, which helps food pass through the intestines, and also has a positive effect on some parameters in the body:

Blood sugar level : Soluble fiber slows down the absorption of macronutrients from food, especially sugars. Thus, it helps control blood glucose levels, which is important for people with insulin resistance, type 2 diabetes, or a predisposition to diabetes.

Blood Cholesterol : Soluble fiber blocks and reduces total dietary cholesterol, including low density lipoprotein. It helps with heart disease and reduces the risk of developing it.

Bile acids : The body uses cholesterol to produce bile acids, which help break down fats and collect metabolic waste.To prevent bile from accumulating in the body, soluble fiber blocks it and removes it in the stool.

Appetite & Weight : Studies show that soluble fiber enhances satiety and satisfies hunger for a long time. Research results indicate weight loss and improvement in body mass index in overweight and obese patients.

Gut microbiota : Soluble fiber is considered a prebiotic food for beneficial gut bacteria.They, in turn, break it down and produce short-chain fatty acids.

Insoluble fiber

Photo by Tom Hermans / Unsplash

Insoluble fiber – fiber resistant to digestive enzymes that pass through the body almost unchanged. They help form feces.

Insoluble fiber stimulates the intestinal wall to produce mucus (mucin) and fluid. The fibers absorb water to form feces, and the extra mucus helps move them through the intestines and out of the body.

How fiber supports microbiota health

The required amount of fiber in the diet improves several indicators of the body at once due to its effect on beneficial and probiotic bacteria.

The effect of dietary fiber on strengthening the immune system, regular bowel movements and decreased appetite has been clinically proven. For example, the fiber inulin promotes the absorption of minerals, but at the same time causes increased gas production.

Use Fiber type Products
Satiety, decreased appetite Dextrin, polydextrose Wheat, potatoes, rice
Improvement in blood sugar Fructooligosaccharides, resistant starch, pyrodextrin Legumes, wheat, rye, onions, garlic, cooked starch, vegetable bananas, chilled potatoes and pasta
Reducing inflammation and strengthening the immune system Arabinogalactan, 𝛃-glucan, fructooligosaccharides, galactooligosaccharides, xylo-oligosaccharides Radishes, carrots, pears, tomatoes, bran, whole grains, mushrooms, legumes, wheat, rye, onions, garlic, chamomile and echinacea (no more than 10 grams per day)
Improvement of blood cholesterol level 𝛃-glucan, cellulose Bran, whole grains, mushrooms, most edible plants
Stool regularity 𝛃-glucan Bran, whole grains, mushrooms
Absorption of calcium and magnesium Inulin Chicory, Jerusalem artichoke, onion, garlic

Fiber consumption reduces overall mortality and deaths from cardiovascular problems by 15–30%.

Butyric acid

Butyric acid or butyrate is a short-chain fatty acid that protects the intestines from inflammation and maintains the integrity of the intestinal walls.

Intestinal bacteria produce butyrate during the fermentation of dietary fiber. Among these bacteria are Faecalibacterium prausnitzii, Roseburia, Eubacterium and some others. With a lack of fiber, butyric acid production is disrupted, which leads to a weakening of the immune system and increases the risk of inflammation.

Butyrate-producing bacteria feed on such types of fiber as arabinoxylan, inulin, pectin, 𝛃-glucan, polydextrose. They are found in barley, oats, chicory, Jerusalem artichoke, onions, garlic, rye, apples, citrus fruits, berries, whole grains, bran, mushrooms.

Fiber as a prebiotic

Prebiotics are types of fibers that, when they enter the intestines, nourish bacteria and stimulate their growth.

These types of fiber include beta-glucans, galacto-, fructo-, xylo- and arabinooligosaccharides, isomaltose, lactulose, oligofructose, inulin, resistant starch.All of them are found in herbal products.

If you took the Atlas Microbiota Test, you may have noticed a lot of confusing terms in the Fiber Intake Rate report. These are all prebiotics that are present in your diet.

Through microbiota testing, we find out which bacteria live and prevail in your gut, what types of fiber they prefer, and how effectively the microbiota copes with the breakdown of fiber. This information is needed to provide personalized nutritional advice.

Nutrition for probiotic bacteria

Gut microbiota is a community of bacteria. The higher their diversity, the better the health indicators. The average and low presence of bacteria indicates an imbalance in the microbiota. Because of this, the body’s potential to defend against disease and inflammation may be reduced.

The more fiber from different sources in your diet, the more beneficial bacteria you have in your gut. For example, the probiotic bacteria Bifidobacterium produces acetate and lactate.They, in turn, are used by bacteria of the species Firmicutes for the production of butyrate.

These bacteria maintain the acidity of the intestines, provide protection against inflammation and pathogens, help to strengthen the immune system, and even reduce stress levels.

Community members such as Akkermansia have other useful qualities. They are present in the intestines of normal weight people and help control weight gain and maintenance.

Effect Fiber type Products
Growth of bifidobacteria Arabinan, arabinoxylan, fructooligosaccharides (FOS), galactooligosaccharides (GOS), galactomannans, mannanoligosaccharides Beetroot, rye, barley, oats, dairy products, chicory, Jerusalem artichoke, onion, garlic, maitake mushrooms, baker’s yeast
Growth of lactic acid bacteria Fructooligosaccharides, inulin, galactan, galactomannan, pullulan, pyrodextrin Thermally processed starch, rye, wheat, onion, garlic, legumes, dairy products, chicory, Jerusalem artichoke, red algae, maitake mushrooms
Growth Akkermansia Arabinoxylan Rye, barley, oats

How to Increase Fiber in Your Diet

It would seem that all that is required is to consume at least 30 grams of fiber from natural products.However, add fiber gradually. Side effects such as bloating, gas and abdominal pain are often associated with dramatic increases in fiber in the diet.

British Food, Lifestyle and Medicine Association recommends using the rainbow principle: eat five servings of vegetables and two fruits daily, each serving one of the colors of the rainbow.

You can track the result using the Nutrition Diary, which is built into the Atlas mobile application.

Convenience foods and fast food are not rich in fiber and contain a lot of salt, sugar and fat.

Ration constructor

🍛 Side dish

Whole grains : wheat, rye, barley, oats, quinoa, buckwheat (these can be both grains and flour).
Legumes : beans, lentils, chickpeas.
Starch : potatoes (cooked and chilled), green bananas, brown rice.

🥬 Additional sources of fiber

Vegetables : raw, fried, boiled, stewed, steamed, dried.
Fruit : preferably fresh, sometimes dried. Best for breakfast or dessert.
Greens : fresh, dried.
Mushrooms : Don’t forget them too.

🥑 Fats

Olive oil : Observe the measure.
Avocado : tasty and rich in fiber, measure is also important.
Greek Yogurt : Probiotic, great for breakfast or as a dressing.

🍋 Seasonings and dressings

Seeds and nuts : Choose raw for a crispy texture.
Citrus fruits : Their juice works well as a dressing
Herbs : They give a rich taste.
Spices : depending on your mood.
Pepper : black, red, mix, dried or fresh
Salt : the main thing is not to oversalt.
Nutritional Yeast : Add cheese flavor and aroma. Better for ready-to-eat meals.

🥚 Proteins

Red meat, seafood and fatty fish : each no more than once a week.
White meat and eggs : in moderation.
Vegetable protein : legumes, tofu.

Should you take fiber as a dietary supplement

It can be difficult to consume the recommended amount of fiber in a regular diet. The theory that in large quantities it promotes weight loss, as well as the availability in the form of nutritional supplements, makes the choice in favor of dietary supplements more attractive.

Studies looking at how fiber supplements affect BMI reduction are conflicting.On the one hand, some dietary supplements satisfy hunger for a long time. This reduces appetite and promotes consumption of fewer calories.

On the other hand, supplements contain pure fiber: unlike vegetables and fruits, they are devoid of vitamins and minerals. In addition, fiber often loses its ability to gel during production – it does not create a viscous mass that makes you feel full.

Fiber in the form of dietary supplements has its benefits: it helps to supplement the amount of fiber in the diet, and is also used to treat certain gastrointestinal disorders.But resorting to this method should be under the supervision of a doctor.

How to assess the health of the microbiota

In the Microbiota Test, we examine the DNA of bacteria from a stool sample. This allows you to find out the level of microbiota diversity, how bacteria cope with the synthesis of butyric acid and vitamins, and what types of fiber you are missing.

We will upload reports on four indicators to your personal account in the Nutrition section:

The test results also include nutritional recommendations based on your gut bacteria composition.

Subscribe to our newsletter at the top of the page and receive a 10% discount on Microbiota Test.

  • ED Jesch & TP Carr, Food Ingredients That Inhibit Cholesterol Absorption, 2017
  • SV Thompson et al., Effects of isolated soluble fiber supplementation on body weight, glycemia, and insulinemia in adults with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials, 2017
  • J Slavin & H Green, Dietary fiber and satiety, 2007
  • D Dhingra et al. , Dietary fiber in foods: a review, 2012
  • World Gastroenterology Organization, Diet and the gut guidelines, 2018
  • Andrew Reynolds et al, Carbohydrate quality and human health: a series of systematic reviews and meta-analyzes, 2019
  • McRorie, Johnson W. Jr PhD, FACG, AGAF, FACN, Evidence-Based Approach to Fiber Supplements and Clinically Meaningful Health Benefits, Part 2 What to Look for and How to Recommend an Effective Fiber Therapy, 2015
  • Max H Pittler, Edzard Ernst, Dietary supplements for body-weight reduction: a systematic review, 2004

How fiber helps to reduce weight and improve health :: Health :: RBC Style

© Dose Juice / Unsplash


Yulia Tsiruleva

10 June 2020

We try to take into account the amount of protein, fat and carbohydrates in order to eat well.But we often forget about another important element – fiber. We figure out how much dietary fiber and why the body needs it.

Fiber is a dietary fiber that does not provide us with energy and cannot be digested by the body, which is why food and beverage manufacturers ignore fiber when listing nutritional information. Why shouldn’t you forget about fiber and what is its benefit?

How fiber works

Fiber fibers are processed by beneficial intestinal microflora and support the stable functioning of the digestive system. Fiber reduces hunger, which helps you avoid overeating and control your weight. Soluble dietary fiber regulates blood sugar and cholesterol levels, while insoluble fiber cleanses the body and detoxifies. And this is only part of the beneficial properties of fiber.

In February this year, Harvard University School of Medicine released 250 studies that support the protective function of dietary fiber.About 30 grams of fiber in your daily diet reduces the risk of heart disease, heart attacks, strokes, type 2 diabetes and colon cancer by 16-24%. According to the US National Library of Medicine, eating a diet rich in fiber reduces deaths from infectious and respiratory diseases from 24% to 56% in men and from 34% to 59% in women.

© Maddi Bazzocco / Unsplash

How much fiber does the body need

The more the better, experts say.American scientists indicate that women and men under 50 need 25 and 38 grams of fiber per day, and after 50 – 21 and 30 grams, respectively. This is roughly equivalent to a cup of lentils, a bowl of boiled beans or broccoli with butter, two pears, a large bowl of tomato and cucumber salad, a serving of vegetable soup, and a handful of prunes.

UK dietitians add that children 2-5 years old require 15 grams of fiber a day, 5-11 years old 20 grams and 11-16 years old 25 grams.The average teenager needs to eat 2-3 vegetables a day – these can be cucumbers, tomatoes or carrots, the same amount of fruits (for example, bananas, kiwi, pears, apples), 1-2 whole grain toast, a serving of vegetable soup, a plate of baked eggplant or boiled broccoli, a serving of whole grain porridge (buckwheat, rice, oatmeal), a cup of dried fruit. Experts advise offering children and teenagers more raw vegetables and fruits, so vegetable and fruit salads and vegetable juices can be added in excess of the minimum daily allowance or instead of hot meals.

How to choose products

Experts recommend natural foods high in fiber. For example, the optimal content will be 6 or more grams of fiber for cereals and muesli, 3 or more for bread and crackers, 4 or more for pasta. It’s important to make sure that whole grains have a minimum of 1 gram of fiber per 10 grams of carbs. The best ratio would be 1: 5. Nutritionists emphasize that the words “multigrain” or “12 grains” in the name themselves do not mean anything – you need to check the list of ingredients.

What foods are rich in fiber

First of all – eat as many natural plant foods as possible. Fresh fruits and nuts are often more expensive than regular sweets, and there is not always time to make inexpensive grains, beans and lentils, but this will help you maintain a balanced diet.

Experts consider the leaders in fiber content:

© Table: Products – leaders in fiber content

How to lose weight with fiber

Soluble fiber helps to deal with belly fat – one of the most dangerous types of obesity according to experts.An additional 10g of plant fiber in the daily diet reduces the risk of gaining excess weight by 3.7%

Fiber keeps the intestinal microflora healthy, reduces the production of hormones that cause hunger and slows down the movement of food in the intestines, helping not to overeat.

As with most weight loss methods, a diet rich in plant fiber alone is not enough to lose weight and sustain gains. General health, dietary habits, sleep quality, and physical activity should also be considered.

To add fiber to your daily diet, you need to eat as many natural plant foods as possible. Fresh fruits and nuts are often more expensive than regular sweets, and there is not always time to make inexpensive grains, beans and lentils, but this will help you maintain a balanced diet.

If you decide to lose weight with the help of fiber, then you should pay attention to:

  • raw and cooked vegetables;
  • whole grain flakes, muesli;
  • oatmeal;
  • soups with vegetables, beans or beans;
  • vegetarian stews made from different varieties of beans and vegetables;
  • salads with seeds, berries and cereals.

In addition, nutritionists advise snacking on broccoli, carrots, beans or cauliflower, season them with hummus or fresh salsa, and add nuts, berries and fruits to simple sugar-free yogurts.

How to determine the approximate amount of fiber in a serving of food:

© Table: Fiber content of food

Daily Diet

The UK National Health Service provides an example of a high fiber diet (approximately 32.5 grams of fiber per day).


Two whole wheat toast, a banana, and a glass of fruit juice – 9.4 grams of fiber.


Jacket baked potatoes, 200 grams of beans in tomato sauce without salt and sugar, and an apple – 13.6 grams of fiber.


Vegetable curry with tomato sauce, onions and spices, whole grain rice, low-calorie fruit yogurt – 6. 5 grams of fiber.Since yoghurt can contain a lot of sugar, you need to check its composition.


A handful of nuts without sugar and salt – 3 grams of fiber.

Points to remember:

  • the body will take time to get used to a large amount of fiber, so it is worth increasing its proportion in the diet gradually;

  • need to drink more water to aid digestion;

  • Fiber in raw vegetables may irritate sensitive stomach and intestines;

  • You should consult your doctor before changing your diet, especially if you have health problems.

Read also: Top 10 Nutrient Foods

Soluble and insoluble dietary fiber

Dietary fiber – the indigestible part of plant material – is represented by the main two types of fiber: soluble and insoluble.

Soluble fiber dissolves easily in water and breaks down into a gel-like substance in the colon.Insoluble fiber does not dissolve in water and remains intact when food passes through the gastrointestinal tract.

The term “fiber” refers to all parts of plant foods that cannot be digested or absorbed by the body. Unlike simple carbohydrates (sugar, most types of bread, soft wheat pasta, etc.), fiber is a complex carbohydrate, it does not raise blood sugar levels. Fiber is found in vegetables, fruits, whole grains, and legumes.The presence of fiber is a must in the diet of every person.

Soluble fiber in the gastrointestinal tract turns into a gel-like substance that is fermented by bacteria in the colon.
Insoluble fiber remains unchanged as it passes through the digestive tract. Since it is completely indigestible, insoluble fiber is not a source of calories.

The health benefits of dietary fiber have been known for a long time.

Soluble fiber is known to reduce fat absorption and help regulate weight; prevents the breakdown and digestion of some of the cholesterol from food and can help lower cholesterol levels or the amount of free cholesterol in the blood; stabilizes blood sugar (glucose) levels by slowing down the absorption of nutrients, including carbohydrates. This means that foods containing soluble fiber are less likely to cause spikes in blood sugar levels, and are even likely to prevent them.So, regular consumption of soluble fiber lowers cholesterol, stabilizes blood sugar, and reduces fat absorption, which can reduce the risk of heart disease and circulatory disorders. Soluble fiber is a prebiotic, it is a substrate for the growth of beneficial microorganisms that live in the colon.

Insoluble fiber is not absorbed by our body and is not fermented in the large intestine. Passing through the gastrointestinal tract, insoluble fiber absorbs liquid and absorbs by-substances formed during digestion.In the presence of insoluble fiber, peristalsis increases and the rate of movement of food along the gastrointestinal tract increases, which prevents the development of constipation. Eating foods rich in indissoluble fiber reduces the risk of intestinal diverticulitis, hemorrhoids, and may reduce the risk of colorectal cancer.

Both types of fiber contribute to the feeling of fullness: soluble fiber slows down the rate of food digestion, and insoluble fiber physically fill the space in the stomach and intestines, contributing to a feeling of fullness.These properties can help people control appetite and manage their weight.

Due to the beneficial properties of fiber, a diet rich in it leads to a decrease in the risk of such diseases as obesity, cardiovascular diseases, diabetes, metabolic syndrome and others.

Currently, on the labeling of some food products, the manufacturer indicates the amount of dietary fiber it contains. It should be noted that in the European Union, an indication on the label that a product is a source of dietary fiber is possible if there is at least 3 g of dietary fiber per 100 g of the product, or at least 1.5 g of fiber per 100 kcal.

The recommended level of daily consumption of dietary fiber in the Russian Federation and other EAEU countries is 30 grams.
Foods rich in fiber include beans, peas, some fruits and vegetables, bran, lentils, artichokes, sweet potatoes, pears, bulgur, raspberries, peeled potatoes, prunes, figs, dates, pumpkin, spinach, raw almonds , raw apples, bananas, oranges, pasta, and whole wheat bread.

So, 1/2 cup of canned beans contains 8.2 g of fiber, 1/2 cup of split peas – 8.1 g, 1/2 cup of boiled lentils – 7.8 g, 1 medium pear contains 4, 3-4.4 g fiber, 2 slices of whole wheat bread contain 4.4 g fiber, 1/2 cup raw raspberries contain 4.0 g, 1/2 cup oat bran contains 3.6 g, 1 average apple – 3.3 g, 1/2 cup of whole wheat spaghetti – contains 3.1 g of fiber.

A balanced, healthy diet contains a mixture of soluble and insoluble fiber. Soluble fiber is more commonly found in foods such as beans, peas, oats, barley, apples, and citrus fruits. Legumes, whole wheat products, bran products, potatoes, cauliflower, and nuts are considered good sources of insoluble fiber.

Also on the market are biologically active food additives, which include soluble and insoluble fibers.However, it should be noted that, unlike food products, such biologically active food supplements do not contain additional vitamins and minerals, including vitamin B and iron.

When shopping for food and preparing food, it is helpful to keep in mind some simple rules for increasing your fiber intake. It is best to choose foods that have whole grains at the top of the ingredient list. Use beans, peas, or lentils in your diet every day.Eat peeled fruits and vegetables whenever possible. Remember that the amount of fiber in many foods will vary depending on whether they are raw or cooked, and the method of preparation (braising, steaming, frying, etc.). Add more beans, peas, or lentils than meat, or make them the main ingredient in pasta, casseroles, or stir-fry dishes. Make sauces with chickpeas, beans, peas, lentils, and other legumes. Eat unsalted nuts and dried fruits, and use them with cereals, salads or yogurt.Prefer brown rice over white

Sources: https://www.medicalnewstoday.com/articles

Nutrition for long-livers: why do we need fiber?

The eating habits of most of the world’s inhabitants have not changed since the 60s. We are accustomed – or so we were told – to eat buckwheat and bread, try to eat less fatty and fried foods, reproach ourselves for an extra piece of cake and absorb as many fruits and vegetables as possible. Why? No one knows.The same “American diet”, which is rapidly creeping into the whole world, bears fruit, and diets are powerless. Why? Are we eating right? What does the latest research show? In this series of articles, we’ll take a look at the nutrition of centenarians and see what scientists have to say about nutrition.

Healthy eating is what it is.

Let’s start with such an interesting but incomprehensible element as fiber.

What is fiber?

Cellulose is a combination of substances (cellulose, pectin, lignin and others) contained in plant food, says Nikolai Karpov , employee of the Department of Anatomy and Physiology of Tyumen State University.The main feature of fiber is its indigestibility in the gastrointestinal tract. The diet of a modern person includes refined products (flour, juices, jams), which contain little fiber. Therefore, many people experience a lack of it. First of all, this is reflected in the work of the digestive tract. What is the benefit? In the stomach, fiber absorbs gastric juice, the volume increases and satiety sets in earlier, which helps a person not to overeat. In the small intestine, fiber inhibits the absorption of simple sugars, so foods with fiber have a low glycemic index.Our body does not feed on fiber, but the bifidobacteria of our intestines feed on it, which means that our immunity is strengthened. To get your daily intake of fiber, you need to eat about a kilogram of fruits and vegetables daily, as well as eat bread made from wholemeal flour or with bran. Or resort to the help of special additives.

Dietary fiber (cellulose) is defined as the sum of polysaccharides and lignin that are not digested by endogenous secretions of the human gastrointestinal tract, adds the therapist of the mobile clinic DOC +, Nadezhda Gorskaya .For example, in herbivores, a special enzyme (cellulase) is responsible for the digestion of fiber, but in humans it is absent in the body, so dietary fiber is not absorbed. They swell under the influence of liquid, thereby creating a feeling of quick satiety, which is especially important for the correction of weight, regulation of sugar and blood cholesterol levels. Dietary fiber helps to cleanse the gastrointestinal tract from undigested food residues, which significantly speeds up the absorption of nutrients into the blood and lymph.

Traditional sources of fiber: dietary fiber of cereals, legumes, vegetables, root crops, fruits, berries, citrus fruits, nuts, mushrooms, algae. These words are supported by the practitioner of weight loss, Elena Kalen – psychologist, expert in the psychology of weight loss, author of weight loss training.

“The body does not have an enzyme capable of breaking down fiber, so when it gets into the stomach and later into the intestine, the fiber swells and irritates the walls, causing them to contract (peristalsis).Thanks to this, food moves through the intestines, digestion and absorption are improved. This means that thanks to fiber, more nutrients and vitamins are supplied to the body. In addition, due to increased peristalsis, the intestines are better cleansed, which ensures faster penetration of nutrients from the intestines into the blood.

The importance of fiber in the diet also lies in the fact that dietary fiber is a source of nutrition for bacteria living in the large intestine. The balance of these bacteria provides the body with stable stools.

Red meat is a source of many useful substances. Here are just a little fiber in it.

In order to ensure a constant supply of fiber to the body, it is necessary to include raw vegetables and fruits, legumes, grains and cereals in the diet. Cooked vegetables and fruits contain less fiber as they have already been processed. If these foods are not enough, there will be permanent digestive problems. ”

Harm to fiber

It was mentioned above that fiber in the intestines swells, and this requires water.Only in this case can the desired effect be obtained. If you increase the amount of fiber in the diet, but at the same time practically do not drink water, you can cause an even greater deterioration in the functioning of the intestines.

Bran is the leader in fiber content. If the bowel function is disturbed and there are no foods containing fiber in the diet, then it is recommended to add bran to the food. One tablespoon in porridge in the morning is enough, because an excess of fiber can harm the body.

Intake of dietary fiber is one of the important ways to normalize bowel function.The digestive system provides the body with building materials, energy and vitamins. If there are disturbances in its work, insufficient absorption and digestion of food, then this will affect the entire body and life expectancy.

How much fiber should you consume?

Doctor-therapist and dietitian of the Online service Doctor Viktoria Griskova argues that there is no need to peel fruits and vegetables. For an adult, the rate of fiber is 25 grams. You need to eat at least 400 grams of fruits and vegetables per day.

Fiber has a positive effect on the human body and digestive system. So, when we eat foods that contain a lot of fiber, a large amount of saliva is secreted in the mouth. Saliva is rich in enzymes and trace elements, it protects teeth from caries, neutralizes acid and has a bactericidal effect.

Then, when fiber enters the stomach, it begins to actively absorb water and increase in volume, which gives a feeling of fullness. This is especially useful for people who are struggling with excess weight.

Once in the intestines, fiber improves the passage of the food bolus, thereby improving the stool. Another important property of fiber is the cleansing of the body from cholesterol, dietary fiber adsorbs cholesterol on itself, preventing it from entering our bloodstream.

Dietary fiber (cellulose) is useful for people suffering from intestinal dysbiosis and increased flatulence. Fiber contributes to the maintenance of intestinal microflora. Suppressing the activity of pathogenic bacteria, it reduces putrefactive processes in the body and improves the excretion of waste products.And as you know, a healthy intestine is the key to strong immunity.

Chemist-technologist and individual entrepreneur in the field of healthy lifestyles Elizaveta Murzich recommends focusing on bran:

“Bran consists of the most valuable thing in cereal grains – grain shells, germ seeds and aleurone layer. These parts of the grains contain all biologically active and useful substances given by the grain nature – more than 90% of the benefits we could get from them if they were not thrown away during the production of flour.The main value of bran is the high content of dietary fiber (fiber). And when the diet lacks fiber, it leads to dysbiosis and is one of the causes of intestinal diseases.

Bran helps to regulate bowel function, improve microflora. The norm of dietary fiber per day is 25-30 g. I think you know that there is no fiber in meat, fish, and other animal products, there is fiber in vegetable products, but there is little of it, and it is really difficult to eat fresh vegetables and fruits in kilograms, especially in winter.Bran contains up to 40%. fiber. 40 g of bran per day is equal to 680 g of boiled carrots, 770 g of boiled cabbage or 1.5 kg of raw apples. The calorie content of bran varies from 160 kcal (or more) per 100 g, where the main share falls on vegetable proteins and carbohydrates, while the fat content in them is extremely low – about 4 g per 100 g of product.

Some berries are rich in fiber

There are many different bran manufacturers in pharmacies. When the bran enters our body, they begin to work like a vacuum cleaner: they collect and remove toxins, cholesterol, radionuclides, salts of heavy metals, and harmful substances. “

Do you really need fiber?

Despite the consensus among nutritionists and nutritionists, there are some studies that deny the benefits of fiber, or reduce it to special conditions, such as increased consumption of refined and “wrong” foods (a well-known vice of our time).

In 1971, Dr. Denis Burkitt, an Irish surgeon, published an article based on his observations of life in Uganda, where he lived at the time. In it, he suggested that a lack of dietary fiber was the cause of many of the problems that were troubling Western society at the time.He decided that it caused bowel cancer, type II diabetes, probably also heart disease, varicose veins, obesity, diverticular disease, appendicitis, gallstones, cavities in the teeth, hemorrhoids, hernias, and constipation.

Dr. Burkitt observed that native Africans produce four times as much feces as English children in school, and do so three times faster. He suspected that this was due to all the fiber that was eaten in Africa. And he suggested that the high rate of bowel movements does not leave time for the development of cancer caused by food contact with our gut.

Since then, there has been a wave of recommendations to consume more fiber.

But in 2002, the respected Cochrane Collaboration reviewed five high quality, controlled trials involving 5,000 patients. And she concluded that there is no evidence that increasing the amount of fiber in the diet reduces the risk of bowel cancer.

This review was followed in 2005 by a study by the Harvard School of Public Health.Her work covered 13 studies involving 725,628 people. And again, the dietary fiber had nothing to do with it. The authors concluded that high fiber intake did not reduce the risk of bowel cancer.

The theory is that fiber reduces the risk of heart disease by lowering the “bad” cholesterol. However, research has shown that while oats do lower cholesterol, trials with other types of fiber have not shown them to be good or bad for this process.There is also no evidence that fiber reduces the risk of dying from heart disease.

With regard to constipation and hemorrhoids, studies have repeatedly found that they could not prove that patients with constipation eat less fiber than those without it. Since fiber is essentially indigestible fiber, consuming too much fiber can lead to constipation. Moreover, the elimination of the abundance of fiber from the diet of people suffering from constipation has led to an improvement in their condition.

Where is the truth? You will have to decide for yourself.

Should Fiber Add or Eliminate? Share your opinion in our Telegram chat.

Disclaimer: The opinions presented in this article are purely advisory in nature.

Benefits of fiber for the human body

You’ve probably already heard that plant fiber is a very important component of a complete diet. But what exactly are its health benefits? Where can you get enough fiber? Let’s find out all the benefits of this important part of our diet, list the best foods high in dietary fiber, and try to increase the fiber content in our daily diet!

If you want to live a long, healthy life, fiber should be your most important dietary component.It must be consumed daily!

The importance of dietary fiber is often underestimated. Most people in developed countries do not consume enough fiber. what about you? Probably, the situation is similar.

For example, only 3% of Americans consume the recommended amount of fiber. Most people eat about 10-15 grams of plant fiber per day, which is much less than the 40 grams recommended by leading experts. Many people are still unaware of the benefits of fiber-rich foods like chia seeds and flax seeds.

Why is dietary fiber good for you? They help the body absorb nutrients from food and flush out toxins. They provide a feeling of fullness and help maintain more consistent energy levels. They are the foundation for proper digestion, maintain a healthy weight, prevent cancer and type 2 diabetes, and have a host of other health benefits.

What is Fiber Really?

You’ve probably figured out by now that you need to eat more fiber.But what is it?

Fiber is found in the cell walls of plants, where it provides structure and functions as a skeleton. It is not absorbed by the human body, therefore it does not provide nutrients or calories. Despite this, fiber fibers are critical to our health.

There are two types of fiber: soluble and insoluble. Each type does a different “job” in our body. Soluble fiber helps to reduce blood glucose and cholesterol levels.It is found in foods such as oatmeal, beans and legumes, and in some fruits and vegetables.

Insoluble Fiber acts as a brush to cleanse the digestive tract. Found in whole grains, beans, bran, fruits and vegetables.

Both types of fiber are found naturally in plant foods. Meat, dairy products, eggs and oils do not contain any vegetable fiber. And products made from sugar or white flour usually contain very little fiber, because any natural fiber is removed from them.

Fiber as the “elixir of youth”

We hear a lot about the power of superfoods, their ability to prolong life and keep us in great shape. Fiber is arguably the best of them all!

The results of analyzes published in the American Journal of Epidemiology show the powerful effects of fiber on our health. Scientists analyzed 17 studies involving nearly a million people and found that every 10 grams of fiber consumed per day reduced the risk of premature death by 10 percent.

Digestive Health Support

Vegetable fiber is known for its ability to improve intestinal motility and counteract constipation, but its healing properties are also manifested in the case of other diseases of the digestive system.

For example, diverticulitis – intestinal inflammation – is one of the most common age-related digestive disorders in the modern world.

Consuming foods rich in insoluble fiber reduces the risk of diverticulitis by 40%, according to a study published in the Journal of Nutrition!

Essential for maintaining a healthy weight

By increasing your intake of plant fiber by only 14 grams per day, you can reduce your calorie intake by 10 percent, while guaranteeing yourself a feeling of fullness and pleasure.

Soluble fiber, mixing with water in the intestine, forms a gel-like substance. This gel slows down the absorption of sugar into the bloodstream. It also activates receptors in the stomach that send a signal to the brain that we are full. So, a person feels full by consuming the same amount of food, even if this food contains fewer calories.

Key role in cancer prevention

Vegetable fiber is an important part of our excretory system.It constantly removes toxins and carcinogens before they can affect the body. For example, it prevents the development of rectal cancer by shortening the transit time of the intestine – literally sweeping away any harmful residues.

In a National Cancer Institute study called Polyp Prevention, published in the Journal of Nutrition, participants were placed on a high-fiber diet (lots of fruits and vegetables). The researchers focused on the study of recurrent colorectal adenomas (polyps).

According to the results of tests, it turned out that the occurrence of relapses of adenomas was directly related to the amount of beans consumed by the test subjects. Scientists believe that beans were the largest source of dietary fiber for most of the study participants.

However, dietary fiber does more than reduce the risk of colorectal cancer. Fiber can help protect us from other forms of cancer, including breast, prostate (prostate), mouth, and throat cancers.

Every 10 grams of plant fiber we consume is associated with a 10 percent reduction in the risk of colorectal cancer and a 5 percent reduction in the risk of breast cancer, according to a study published in the Annals of Oncology.

Another study published in the Official Journal of the American Academy of Pediatrics found that women who ate 28 grams of fiber a day had a 24% lower risk of developing breast cancer before menopause compared to women who ate only 14 grams a day. …

Women who ate more fiber also reduced their lifetime risk of breast cancer by 16%.

Dietary fiber for heart health

Many cardiologists recommend oatmeal for breakfast.Their main argument is that oatmeal contains a lot of soluble fiber.

Scientists do not yet fully understand the mechanism by which fiber lowers cholesterol, but soluble oat fiber can lower bad cholesterol (LDL) without affecting good cholesterol, according to data published in the American Journal of Clinical Nutrition. (HDL).

In a study of 22 different publications in the respected British medical journal BMJ, it was found that a higher intake of dietary fiber was associated with a lower risk of cardiovascular disease and coronary artery disease.

Foods high in fiber may also have a positive effect on lowering blood pressure and reducing inflammation.

Blood sugar control and counteracting type 2 diabetes

Dietary fiber has the unique ability to regulate blood sugar levels. This is why nutritionists recommend that people with diabetes consume beans and legumes. These fiber-rich energy sources help slow the absorption of glucose as well as regulate blood sugar levels over time.

In a study published in NutritionJournal, researchers tested the glycemic response of traditional beans in rice dishes versus pure rice.

Seventeen diabetic men and women were divided into groups, one of which was fed regular white rice and the other white rice with beans. The researchers measured the participants’ blood glucose levels after 90, 120, and 150 minutes. The results showed that the group that ate the beans with rice had better blood sugar control.

So, if you have diabetes, prediabetes, or just want more stable blood sugar, feel better, and have more energy, you need to eat fiber-rich, low-sugar plant foods (legumes, chia seeds, flax seeds).

Our clients with type 2 diabetes say that simply adding chia seeds (1 tablespoon per day – about 5 g of fiber) to their daily diet, within a week, reduced their blood sugar levels from 11 to 5.5-7 mmol / l.

Fiber helps to detoxify the body

Through a process called osmosis, dietary fiber absorbs fluid containing toxins and flushes these substances out of the body.

How do I get enough fiber daily?

Now that you have learned about all the benefits of dietary fiber, here are some simple ways to increase their amount in your diet:

  • substitute beans for beef or pork,
  • Have breakfast with oatmeal with berries or chopped fruits,
  • Snack on foods rich in dietary fiber (with spelled or hemp bran),
  • Give up cookies, crackers, chips and sodas,
  • choose whole grain bread over white flour,
  • Add chia and flax seeds to your daily meals (stews, soups, salads).

Different foods contain different amounts of fiber. To determine how much plant fiber you are eating, write down everything you ate and drank during the day. Next, count your grams of fiber using the table below.

Product (100 g)

Fiber in grams m ah

Vegetable water cabbage soup

Sugar corn


Brussels sprouts (boiled)


Green beans (baked)


Broccoli (boiled)


Pumpkin (boiled)


Onions (fresh)


Beets (boiled)


Carrots (fresh)


Carrots (boiled)


Cabbage (stewed)


Mashed potatoes


Cabbage (fresh)

2 – 2.4

Cauliflower (stewed)


Celery (stems)


Bell pepper (fresh)

1.4 – 1.7

Spinach (boiled)


Sweet potato (boiled)




Chinese cabbage




Greenhouse tomatoes


Fruits, dried fruits, berries

Dried apricots









3.7 – 6.5

Pear with peel



2.4 – 3.1

Apple with peel

2 – 4




2 – 2.2









Grapes (berries with skin)




Melon (pulp)


Bread, pasta, cereals

Wheat bran


Whole grain bread

6.8 – 9.2

Oatmeal “Hercules”


Rye bread


Pasta from durum wheat


Buckwheat kernels (boiled)


Wheat bread (white)


White rice (boiled)


Armenian thin bread


Beans, nuts, seeds

Chia seeds


Flax seeds








Spelled groats


Chickpeas – chickpeas


Raw almonds


Green peas


Wheat flour (boiled)


Cashews, raw


If your diet consists mainly of whole grains, fruits, vegetables, and beans, you are probably getting enough fiber.

However, if you prefer meat, dairy products, white bread, cookies, crackers, chips, reaching 40 grams of fiber per day will be a challenge.

Evaluation of fiber in the diet

Less than 20 grams of fiber per day.

Unfortunately, this indicator of the amount of dietary fiber in the diet is fairly typical for most people in the modern industrial world.

Eating so little fiber means an increased risk of obesity, constipation and other digestive disorders, as well as chronic diseases, including heart disease and some forms of cancer.

Fortunately, this can be easily remedied by including more fiber-rich foods in your diet.

20-39 grams of fiber per day.

This diet is better than most people in developed countries, but not yet perfect.

Focus on limiting fiber-free foods by adding more bran, nuts and legumes to your daily meals. This will help maintain a healthy body weight as well as minimize the risk of developing chronic diseases.

40+ g fiber per day.

This diet is filled with whole, plant-based foods. By sticking to it, you will be part of the 3% of the world’s population who actually receive the recommended amount of fiber.Keep it up!

Example of a fiber-rich diet

If most people consume only 10-15 grams of fiber a day, you are wondering how you can eat 40 or more grams of fiber?

This is easier than you think. This is what your typical diet might look like:

  • Upon awakening: 3-4 teaspoons of chia or flax seeds, pre-soaked overnight, taken with warm water (4-6 g of fiber).
  • Breakfast: oatmeal with cinnamon, spelled or hemp bran and diced apple (4 g fiber in oatmeal, 0.5 g in bran, 3 g in apple = 7.5 g).
  • Lunch: cabbage or spinach salad, garnished with grated carrots and beets, and a portion of chickpeas (4 g fiber in spinach or cabbage, 2 g in carrots and beets, 7 g in chickpeas = 13 g).
  • Snack: one banana or orange (3-4 g fiber).
  • Dinner: Lentils with Vegetable Stew and Rye Bread (7 g of fiber in lentils, 4 g in vegetables, 4 g in 2 slices of bread = 15 g).

Total fiber: 42.5 – 45.5 g.

Some people use fiber supplements that are unfortunately of limited value. They lack the nutritional factors, beneficial vitamins, minerals, antioxidants, and phytochemicals that accompany fiber in wholesome plant foods.

Chia seeds, flax seeds and legumes are preferred among whole, fiber-rich plant foods.

Now that you know your fiber score and better understand how to get enough fiber from your diet, try to achieve 40 grams of fiber per day on a consistent basis.

If you are new to high fiber intake, it is best to add it gradually to your diet. Increasing fiber too quickly can lead to bloating, gas, or other unwanted side effects. It is also important to drink plenty of water while increasing your fiber intake.When your body gets used to more fiber in your food, you won’t experience any discomfort.

We hope we have fully answered the question: Why is it important to consume fiber? Now you know how to get enough fiber in your diet.

You can get the full benefit of this vital nutrient by eating a mostly whole, plant-based diet. Eating more vegetables and fruits is a great way to prolong life and maintain good health.

90,000 Fiber – “secret weapon” for digestion

Back in the 70s of the last century, fiber, known at that time more under the name of ballast substances, was really considered unnecessary ballast for our body. In this regard, they tried to free all food from it as much as possible, for example, grind the flour as finely as possible, separate the rice from the shell, eat apples, pears and other fruits without a peel.

The situation changed only when the British doctor Denis Burkitt returned from a business trip to Africa and outlined his hypothesis about ballast substances in one of his works.He wrote that Africans are less likely to suffer from obesity, gallstones and diabetes and almost never get bowel cancer, because they consume 60 grams of fiber daily. Moreover, this figure was several times higher than the amount of fiber that was in the diet of residents of European regions and the United States. On average, every inhabitant at that time had 10 g of fiber.

Since then, the attitude towards fiber has changed dramatically, and more and more information about its usefulness for our body began to appear.

What is fiber?

Fiber is a polysaccharide, otherwise dietary fiber that is not able to be digested in our body and is found in food only of plant origin. The reason that fiber is partially digested by our body or not digested at all is that in our stomach either there are no enzymes that can break it down, or there are carrier proteins that can transfer it from the intestines through the mucous membranes. Thus, our body cannot process fiber, therefore it removes it from the body almost unchanged.

Unlike proteins, fats and other carbohydrates, and fiber itself is a complex carbohydrate, it contains almost no calories. There are only 2 calories per 100 grams of fiber!

Types of fiber

It is customary to distinguish between two types of fiber:

Soluble fiber has the ability to lower blood cholesterol levels. By binding to bile acids in the colon, it removes them from the body. And since our body needs cholesterol to make bile acids, blood levels drop dramatically.

In addition, soluble fiber has a positive effect on blood sugar levels, which is why it is often recommended for people with diabetes. After eating, it prevents the rapid release of sugar into the bloodstream.

The main sources of soluble fiber are vegetables and fruits.

Insoluble fiber supports our health in a slightly different way. It has the ability to bind water and swell, which occurs in the colon.At the same time, she is able to absorb a huge amount of liquid, which is 100 times her own weight! Due to this, the intestines are filled, which stimulates its peristalsis and improves the condition of the stool.

In addition, insoluble fiber has a positive effect on the intestinal flora, since it is the main food for the “good” bacteria that inhabit it, which multiply especially quickly when a sufficient amount of fiber is supplied to the body. Due to this, fiber indirectly affects the strengthening of immunity, since the protective function of the intestinal mucous membranes improves.

The main sources of insoluble fiber are cereals.

Soluble fiber Insoluble fiber
Substances Food Substances Food
Guar Apples Lignin Rye
Pectins Beans, peas Cellulose Wheat
Carrageena Potatoes Hemicellulose Whole grain rice
Agar Barley Apple peel
Whole grain oats Cabbage
Berries Carrot
Citrus Beet

Foods containing fiber

So, the main sources of fiber are the following foods:

  • Fruits, eg apples, pears, berries, kiwi, citrus fruits;
  • Vegetables, eg broccoli, carrots, potatoes, cabbage;
  • Whole grain products;
  • Nuts and seeds;
  • Legumes, eg peas, beans, lentils;
  • Dried fruits.
Food product Amount of fiber per 100 g of product in grams
Wheat bran 45
Flaxseed 35
Soy bread 23
Prunes 17.8
Black root 18.4
Jerusalem artichoke 12.1
Artichoke 11.4
Fruit muesli 10.3
Dried Figs 9.6
Hazelnut 7.6
Rye / wheat bread 7.5
Raisins 6.7
Peas 5.3
Coarse flour noodles 5.1
Beans 5
Chickpeas 4.4
Lentils 3.6
Cabbage 3
Broccoli 3
Pear 2.8
Apple 2
Tomatoes 1.3
Cucumber 0.9

At the same time, the amount of fiber obtained depends not only on individual food products, but also on the methods of their preparation.Its level is higher if you consume fruits with peels, carrots raw, and vegetables, if possible, do not grind too much. If foods are sautéed or mashed, the fiber level in them approaches zero.

Attention! If your diet is high in fiber, you should also monitor the amount of fluids you drink per day, as fiber can bind water in the intestines. At the same time, one should not be too zealous and lean exclusively on dietary fiber, since they absorb not only water, but also minerals and trace elements, which can provoke their deficiency.That is why experts recommend not to exceed a portion and consume 25-30 g of fiber daily.

In addition, in particularly sensitive people, the consumption of large amounts of fiber can lead to flatulence. That is why it is important to gradually accustom your body to increasing portions of fiber. For example, you can first replace white bread with whole grain, instead of ordinary noodles, eat noodles from wholemeal flour and consume a little vegetables and fruits during the day, preferably with a peel.

Does coffee contain fiber?

According to recent research, everyone’s favorite morning invigorating drink, coffee, is also a source of fiber. One cup contains up to 1.5 g of ballast substances, while instant coffee is the leader, followed by espresso, and coffee brewed in a coffee maker closes the list, since fiber is sifted out during the filtration process and does not get into the cup.

Other beneficial effects of fiber

  • Fiber prolongs chewing activity, which contributes to increased salivation, lower acidity and prevention of caries.Thus, it has a positive effect on the condition of the teeth.
  • Fiber increases the residence time of food gruel (chyme) in the stomach, which contributes to prolonged satiety and almost eliminates the likelihood of feeling hungry.
  • Fiber reduces the time of passage of chyme through the gastrointestinal tract, which prevents contact of carcinogenic substances with mucous membranes and reduces the likelihood of inflammatory reactions and diarrhea, the formation of polyps and hemorrhoids, as well as the risk of developing intestinal cancer.
  • Fiber makes stools normal and prevents constipation.
  • Fiber neutralizes gastric juice, which prevents heartburn.

As you can see, fiber provides invaluable benefits to our body, so it is extremely important to try to balance your diet in such a way that there is enough of it. At the same time, one should not rush to extremes, since in addition to fiber, the body needs other equally valuable nutrients. As with any food, she will only be a friend if you do not overeat.No wonder they say that everything is good in moderation.



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