What are the essential health benefits of dietary fiber. How much fiber should you consume daily. Which types of fiber are most beneficial for your gut health. How does fiber impact weight loss and blood sugar control. Can increasing fiber intake reduce the risk of chronic diseases.

Understanding Dietary Fiber: Types and Functions

Dietary fiber is a non-digestible carbohydrate found in plant-based foods. It plays a crucial role in maintaining overall health and wellness. Fiber is typically categorized into two main types:

• Soluble fiber: Dissolves in water and can be metabolized by beneficial gut bacteria
• Insoluble fiber: Does not dissolve in water and passes through the digestive system largely intact

However, a more practical classification of fiber is based on its fermentability – whether it can be used by friendly gut bacteria or not. Many foods contain both soluble and insoluble fibers, and there is often overlap between these categories.

Health authorities recommend daily fiber intake of 38 grams for men and 25 grams for women. Are you meeting these recommendations? Incorporating a variety of fiber-rich foods into your diet can help you reach these goals and reap the numerous health benefits associated with adequate fiber consumption.

The Gut Microbiome: How Fiber Nourishes Beneficial Bacteria

Did you know that the bacteria living in your body outnumber your own cells by a factor of 10 to 1? The majority of these microorganisms reside in your gut, particularly in the large intestine. This diverse community of bacteria, known as the gut flora or microbiome, plays a vital role in various aspects of health, including:

• Weight management
• Blood sugar control
• Immune function
• Brain function

Fiber serves as a primary food source for these beneficial gut bacteria. While most carbohydrates, proteins, and fats are absorbed in the small intestine, fiber remains largely undigested until it reaches the large intestine. Here, gut bacteria possess the enzymes necessary to break down and ferment certain types of fiber.

This fermentation process produces short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate. These SCFAs, particularly butyrate, provide numerous health benefits, including:

• Nourishing cells in the colon
• Reducing gut inflammation
• Improving digestive disorders like irritable bowel syndrome, Crohn’s disease, and ulcerative colitis

By consuming adequate amounts of fermentable fiber, you can optimize the function of your gut microbiome and support overall health.

Fiber and Weight Management: The Connection Explained

Can fiber help you lose weight? Certain types of fiber have been shown to aid in weight loss by reducing appetite and calorie intake. Here’s how fiber contributes to weight management:

1. Increasing feelings of fullness
2. Slowing nutrient absorption
3. Reducing overall calorie intake

However, it’s important to note that not all types of fiber have the same effect on weight. Some soluble fibers, such as glucomannan, have been particularly effective in promoting weight loss. These fibers can absorb water in the intestine, creating a gel-like substance that slows digestion and increases satiety.

If you’re looking to incorporate more weight-management-friendly fiber into your diet, consider foods rich in soluble fiber such as oats, beans, and fruits like apples and berries.

Blood Sugar Control: Fiber’s Role in Diabetes Prevention and Management

How does fiber impact blood sugar levels? Soluble fiber has been shown to have a significant effect on blood sugar control. When you consume foods rich in soluble fiber, it forms a gel-like substance in your digestive tract, which can slow down the absorption of sugar into your bloodstream.

This slower absorption helps prevent rapid spikes in blood sugar levels, which is particularly beneficial for individuals with diabetes or those at risk of developing the condition. Some studies have shown that a high-fiber diet can reduce the risk of developing type 2 diabetes by up to 20-30%.

Incorporating fiber-rich foods into your meals can help stabilize blood sugar levels throughout the day. Some excellent sources of soluble fiber include:

• Oats and barley
• Legumes (beans, lentils, peas)
• Fruits like apples, pears, and berries
• Vegetables such as carrots and Brussels sprouts

By including these foods in your diet, you can better manage your blood sugar levels and reduce your risk of developing diabetes-related complications.

Heart Health: The Cardiovascular Benefits of a High-Fiber Diet

A diet rich in fiber has been associated with a reduced risk of heart disease. How does fiber contribute to cardiovascular health? Here are several ways:

1. Lowering cholesterol levels: Soluble fiber can bind to cholesterol in the digestive system, preventing its absorption and helping to reduce LDL (bad) cholesterol levels.
2. Reducing blood pressure: Some studies have shown that increased fiber intake can help lower blood pressure, a major risk factor for heart disease.
3. Decreasing inflammation: Fiber’s anti-inflammatory properties may help reduce the risk of heart disease by lowering overall inflammation in the body.
4. Improving insulin sensitivity: By helping to regulate blood sugar levels, fiber can improve insulin sensitivity, which is beneficial for heart health.

To reap these cardiovascular benefits, aim to include a variety of fiber-rich foods in your diet, such as whole grains, legumes, fruits, and vegetables. Remember, consistency is key when it comes to incorporating fiber into your diet for heart health.

Digestive Health: How Fiber Supports a Healthy Gut

Fiber plays a crucial role in maintaining digestive health. How does it benefit your gut? Here are several ways:

• Promoting regular bowel movements: Insoluble fiber adds bulk to stool, helping to prevent constipation and promote regularity.
• Preventing diverticular disease: A high-fiber diet may reduce the risk of developing diverticulitis, a condition characterized by inflammation of the digestive tract.
• Supporting a healthy gut microbiome: As discussed earlier, fiber serves as a prebiotic, nourishing beneficial gut bacteria.
• Reducing the risk of hemorrhoids: By promoting softer, more regular stools, fiber can help prevent and alleviate hemorrhoids.

While increasing your fiber intake, it’s important to do so gradually and drink plenty of water. This approach can help minimize potential side effects such as bloating or gas as your digestive system adjusts to the increased fiber consumption.

Cancer Prevention: The Potential Protective Effects of Dietary Fiber

Research has suggested that a high-fiber diet may help reduce the risk of certain types of cancer, particularly colorectal cancer. How might fiber contribute to cancer prevention?

1. Diluting carcinogens: Fiber can bind to potentially harmful substances in the digestive tract, diluting their concentration and reducing exposure to the intestinal lining.
2. Promoting faster transit time: By speeding up the passage of waste through the colon, fiber may reduce the time that potentially harmful substances are in contact with the intestinal walls.
3. Producing beneficial compounds: When gut bacteria ferment fiber, they produce short-chain fatty acids, which may have anti-cancer properties.
4. Supporting overall gut health: A healthy gut microbiome, supported by adequate fiber intake, may play a role in reducing cancer risk.

While more research is needed to fully understand the relationship between fiber and cancer prevention, maintaining a diet rich in diverse fiber sources is a prudent approach to support overall health and potentially reduce cancer risk.

Incorporating Fiber-Rich Foods into Your Diet

Now that we’ve explored the numerous health benefits of dietary fiber, you might be wondering how to increase your fiber intake. Here are some practical tips for incorporating more fiber-rich foods into your daily diet:

• Start your day with a high-fiber breakfast: Choose whole-grain cereals, oatmeal, or add berries and nuts to your morning yogurt.
• Snack on fruits and vegetables: Keep cut-up veggies and whole fruits readily available for quick, fiber-rich snacks.
• Choose whole grains: Opt for whole-grain bread, pasta, and rice instead of their refined counterparts.
• Include legumes in your meals: Add beans, lentils, or chickpeas to salads, soups, and main dishes.
• Experiment with new plant-based recipes: Try incorporating more plant-based meals into your weekly menu to naturally increase your fiber intake.

Remember to increase your fiber intake gradually and drink plenty of water to allow your digestive system to adjust. By making these simple changes, you can significantly boost your fiber consumption and enjoy the numerous health benefits associated with a high-fiber diet.

Potential Side Effects and Precautions

While dietary fiber offers numerous health benefits, it’s important to be aware of potential side effects, especially when significantly increasing your intake. Some individuals may experience:

• Bloating
• Gas
• Abdominal discomfort
• Changes in bowel habits

These side effects are usually temporary and subside as your body adjusts to the increased fiber intake. To minimize these effects:

1. Increase fiber intake gradually over several weeks
2. Drink plenty of water to help fiber move through your digestive system
3. Choose a variety of fiber sources to ensure a balance of soluble and insoluble fibers
4. If you have a digestive condition, consult with your healthcare provider before significantly increasing your fiber intake

By taking these precautions, you can safely incorporate more fiber into your diet and reap its numerous health benefits.

The Future of Fiber Research

As our understanding of the gut microbiome and its impact on overall health continues to grow, so does the interest in dietary fiber research. What areas of fiber research show promise for the future?

• Personalized nutrition: Researchers are exploring how individual differences in gut microbiota composition may influence the effects of different types of fiber.
• Novel fiber sources: Scientists are investigating new sources of dietary fiber, including those derived from algae and fungi.
• Fiber and mental health: Emerging research is examining the potential links between fiber intake, gut health, and mental well-being.
• Fiber supplements: Studies are ongoing to develop more effective and targeted fiber supplements for specific health conditions.

As research in these areas progresses, we may gain even more insights into the diverse roles of dietary fiber in human health and develop more tailored approaches to fiber consumption for optimal well-being.

Why Is Fiber Good for You? The Crunchy Truth

Some types of fiber may benefit your health, including your gut microbiome, blood sugar, and the walls of your colon.

Fiber is one of the main reasons whole plant foods are good for you.

Growing evidence shows that adequate fiber intake may benefit your digestion and reduce your risk of chronic disease.

Many of these benefits are mediated by your gut microbiota — the millions of bacteria that live in your digestive system.

However, not all fiber is created equal. Different types have different health effects.

This article explains the evidence-based health benefits of fiber.

What is fiber?

Put simply, dietary fiber is a non-digestible carbohydrate found in foods.

It’s split into two broad categories based on its water solubility:

1. Soluble fiber: dissolves in water and can be metabolized by the “good” bacteria in the gut
2. Insoluble fiber: does not dissolve in water

Perhaps a more helpful way to categorize fiber is as fermentable versus non-fermentable, which refers to whether friendly gut bacteria can use it or not.

It’s important to keep in mind that there are many different types of fiber. Some of them have important health benefits, while others are mostly useless.

There is also a lot of overlap between soluble and insoluble fibers. Some insoluble fibers can be digested by the good bacteria in the intestine, and most foods contain both soluble and insoluble fibers.

Health authorities recommend that men and women eat 38 and 25 grams of fiber per day, respectively.

Summary

Non-digestible carbohydrates are collectively known as fiber. They are most often categorized as soluble or insoluble.

Fiber feeds “good” gut bacteria

The bacteria that live in the human body outnumber the body’s cells 10 to 1. Bacteria live on the skin, in the mouth, and in the nose, but the great majority live in the gut, primarily the large intestine (1).

Five hundred to 1,000 different species of bacteria live in the intestine, totaling about 38 trillion cells. These gut bacteria are also known as the gut flora (2, 3).

This is not a bad thing. In fact, there is a mutually beneficial relationship between you and some of the bacteria that live in your digestive system.

You provide food, shelter, and a safe habitat for the bacteria. In return, they take care of some things that the human body cannot do on its own.

Of the many different kinds of bacteria, some are crucial for various aspects of your health, including weight, blood sugar control, immune function, and even brain function (4, 5, 6, 7, 8).

You may wonder what this has to do with fiber. Just like any other organism, bacteria need to eat to get energy to survive and function.

The problem is that most carbs, proteins, and fats are absorbed into the bloodstream before they make it to the large intestine, leaving little for the gut flora.

This is where fiber comes in. Human cells don’t have the enzymes to digest fiber, so it reaches the large intestine relatively unchanged.

However, intestinal bacteria do have the enzymes to digest many of these fibers.

This is the most important reason that (some) dietary fibers are essential for health. They feed the “good” bacteria in the intestine, functioning as prebiotics (9).

In this way, they promote the growth of “good” gut bacteria, which can have various positive effects on health (10).

The friendly bacteria produce nutrients for the body, including short-chain fatty acids such as acetate, propionate, and butyrate, of which butyrate appears to be the most important (11).

These short-chain fatty acids can feed the cells in the colon, leading to reduced gut inflammation and improvements in digestive disorders such as irritable bowel syndrome, Crohn’s disease, and ulcerative colitis (12, 13, 14).

When the bacteria ferment the fiber, they also produce gases. This is why high fiber diets can cause flatulence and stomach discomfort in some people. These side effects usually go away with time as your body adjusts.

Summary

Consuming adequate amounts of soluble, fermentable fiber is very important for optimal health because it optimizes the function of the friendly bacteria in your gut.

Some types of fiber can help you lose weight

Certain types of fiber can help you lose weight by reducing your appetite.

In fact, some studies show that increasing dietary fiber can cause weight loss by automatically reducing calorie intake (15, 16).

Fiber can soak up water in the intestine, slowing the absorption of nutrients and increasing feelings of fullness (17).

However, this depends on the type of fiber. Some types have no effect on weight, while certain soluble fibers can have a significant effect (18, 19, 20, 21).

A good example of an effective fiber supplement for weight loss is glucomannan.

Summary

Some types of fiber can cause weight loss by increasing feelings of fullness, leading to a reduced calorie intake.

Fiber can reduce blood sugar spikes after a high carb meal

High fiber foods tend to have a lower glycemic index than refined carb sources, which have been stripped of most of their fiber.

However, scientists believe that only high viscosity, soluble fibers have this property (22).

Including these viscous, soluble fibers in your carb-containing meals may cause smaller spikes in blood sugar (23).

This is important, especially if you’re following a high carb diet. In this case, the fiber can reduce the likelihood of the carbs raising your blood sugar to harmful levels.

That said, if you have blood sugar issues, you should consider reducing your carb intake — especially your intake of low fiber, refined carbs such as white flour and added sugar.

Summary

Foods that contain viscous fiber have a lower glycemic index and cause smaller spikes in blood sugar than foods that are low in fiber.

Fiber can reduce cholesterol, but the effect isn’t huge

Viscous, soluble fiber can also reduce your cholesterol levels.

However, the effect isn’t nearly as impressive as you might expect.

A review of 67 controlled studies found that consuming 2–10 grams of soluble fiber per day reduced total cholesterol by only 1.7 mg/dl and LDL (bad) cholesterol by 2.2 mg/dl, on average (24).

But this also depends on the viscosity of the fiber. Some studies have found impressive reductions in cholesterol with increased fiber intake (25, 26).

Whether this has any meaningful effects in the long term is unknown, although many observational studies show that people who eat more fiber have a lower risk of heart disease (27).

Summary

Some types of fiber can reduce cholesterol levels. However, most studies show that the effect isn’t very large, on average.

What about fiber and constipation?

One of the main benefits of increasing fiber intake is reduced constipation.

Fiber is believed to help absorb water, increase the bulk of stool, and speed up the movement of stool through the intestine. However, the evidence is fairly conflicting (28, 29).

Some studies show that increasing fiber can improve symptoms of constipation, but other studies show that removing fiber improves constipation. The effects depend on the type of fiber.

In one study in 63 individuals with chronic constipation, going on a low fiber diet fixed their problem. The individuals who remained on a high fiber diet saw no improvement (30).

In general, fiber that increases the water content of your stool has a laxative effect, while fiber that adds to the dry mass of stool without increasing its water content may have a constipating effect.

Soluble fibers that form a gel in the digestive tract and are not fermented by gut bacteria are often effective. A good example of a gel-forming fiber is psyllium (22).

Other types of fiber, such as sorbitol, have a laxative effect by drawing water into the colon. Prunes are a good source of sorbitol (31, 32).

Choosing the right type of fiber may help your constipation, but taking the wrong supplements can do the opposite.

For this reason, you should consult a healthcare professional before taking fiber supplements for constipation.

Summary

The laxative effects of fiber differ. Some fibers reduce constipation, but others increase constipation. This appears to depend on the individual and the type of fiber.

Fiber might reduce the risk of colorectal cancer

Colorectal cancer is the third leading cause of cancer deaths in the world (33).

Many studies have linked a high intake of fiber-rich foods with a reduced risk of colon cancer (34).

However, whole, high fiber foods like fruits, vegetables, and whole grains contain various other healthy nutrients and antioxidants that may affect cancer risk.

Therefore, it’s difficult to isolate the effects of fiber from other factors in healthy, whole-food diets. To date, no strong evidence proves that fiber has cancer-preventive effects (35).

Yet, since fiber may help keep the colon wall healthy, many scientists believe that fiber plays an important role (36).

Summary

Studies have associated a high fiber intake with a reduced risk of colon cancer. However, correlation doesn’t equal causation. To date, no studies have confirmed that fiber has direct benefits for cancer prevention.

The bottom line

Dietary fiber has various health benefits.

Not only does it feed your gut bacteria, but fermentable fiber also forms short-chain fatty acids, which nourish your colon wall.

Additionally, viscous, soluble fiber may reduce your appetite, lower your cholesterol levels, and decrease the rise in blood sugar after high carb meals.

If you’re aiming for a healthy lifestyle, try to get a variety of fiber types from whole fruits, vegetables, and grains.

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 called glucose, 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 25 to 35 grams of fiber per day for good health, but most Americans get only about 15 grams a day. Great sources are whole grains, whole fruits and vegetables, legumes, and nuts.

Types of Fiber

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, chia seeds, 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 whole wheat products (especially wheat bran), quinoa, brown rice, legumes, leafy greens like kale, almonds, walnuts, seeds, and fruits with edible skins like pears and apples.

Fiber and Disease

Fiber appears to lower the risk of developing various conditions, including heart disease, diabetes, diverticular disease, and constipation. Fiber’s beneficial role in the gut microbiome may produce anti-inflammatory effects that alleviate the chronic inflammation associated with these conditions. [2]

Heart disease

Soluble fiber attracts water in the gut, forming a gel, which can slow digestion. This may help prevent blood glucose surges after eating and reduce hunger. Control of blood glucose and weight is important because these are risk factors for diabetes, a condition which doubles the risk of developing heart disease.

Soluble fiber may also lower blood cholesterol by interfering with bile acid production. Cholesterol is used to make bile acids in the liver. Soluble fiber binds to bile acids in the gut and excretes them from the body. Because of this reduced amount of available bile acids, the liver will pull cholesterol from the blood to make new bile acids, thereby lowering blood cholesterol. [3] A meta-analysis of 67 controlled trials found a modest benefit of dietary soluble fiber in lowering total and LDL cholesterol. [4]

Epidemiological studies find that a high intake of dietary fiber is associated with a lower risk of heart disease and deaths from cardiovascular disease. [5-7] In large cohorts of male and female health professionals, researchers found that higher intakes of cereal fibers were associated with a lower risk of heart disease and heart attacks. [8,9] Keep in mind that cereal fiber doesn’t necessarily refer to the aisle of boxed breakfast cereals in your local supermarket. “Cereals” in these studies referred to the seeds of minimally refined whole grains that include the germ, bran, and endosperm. Examples are steel-cut oats, quinoa, brown rice, millet, barley, and buckwheat.

A 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: high blood pressure, high insulin levels, excess weight (especially around the belly), high triglyceride levels, and low HDL (good) cholesterol. [10,11]

Type 2 diabetes

Diets low in fiber, especially insoluble types, may increase the risk of type 2 diabetes (T2DM). Large cohort studies of women found that a diet low in fiber (especially lacking cereal fibers) but containing foods with a high glycemic index (causing blood glucose surges) increased the risk of developing T2DM. [12,13] Other large cohorts of male and female health professionals have found that high-fiber whole grains (brown rice, rye, oats, wheat bran) are most strongly associated with lower diabetes risk. [14,15] Fibers from fruits and vegetables do not appear to have as strong an association. [16]

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

Breast cancer

A prospective cohort study of more than 90,000 premenopausal women found that a higher fiber intake as well as eating fiber during adolescence reduced breast cancer risk. When comparing the highest to lowest intakes of fiber, there was a 25% reduced risk of breast cancer. [32] This protection of dietary fiber on breast cancer risk was also found in a later meta-analysis of 17 prospective cohort studies when comparing highest to lowest fiber intakes. It was found protective from both premenopausal and postmenopausal breast cancers. [33]

A high-fiber diet was also associated with a lower risk of benign breast disease, a risk factor in adolescents for the later development of breast cancer. [34]

Colorectal cancer

Earlier epidemiological studies show mixed results on the association of fiber and colorectal cancer (CRC). [27]

One reason may be due to differing effects of fiber on specific subtypes of CRC. When accounting for this, fiber was found to be protective with certain subtypes. [28] A meta-analysis of prospective cohort studies found fibers from fruits, vegetables, and legumes to offer some protection from CRC, but cereal fibers showed a stronger association with CRC prevention. [29] Other later meta-analyses have also found significant associations between a high-fiber diet and lower risk of CRC. [30,31]

Constipation

Constipation is generally defined as having three or fewer bowel movements a week, difficulty or pain passing bowel movements, or small hard “pebbly” stool. Occasional bouts of constipation are common, but chronic constipation that does not resolve can lower quality of life and lead to symptoms of bloating, cramping, and even nausea. Chronic constipation increases the risk of diverticular disease and hemorrhoids.

Lifestyle behaviors that help relieve constipation include eating more fiber from fruits, vegetables, and whole grains; drinking more water; and regular exercise. There are various reasons why fiber reduces constipation. Some types of soluble fiber bind to water, creating a gel that helps to soften and bulk stool. Insoluble fibers mildly irritate the intestinal lining, which stimulates the secretion of water and mucus to encourage movement of stool. [26] Certain fibers act as prebiotics, or food for gut bacteria, which ferments fibers into short chain fatty acids and increases water in the intestines to produce softer, easier-to-pass stools. [26]

Because of the differing actions of various fiber types with constipation, a range of high-fiber foods from whole grains, fruits, legumes, and vegetables is recommended. It is suggested to increase fiber intake gradually, because a sudden significant increase in dietary fiber can cause bloating and cramping. Drinking more fluids while eating more fiber can also help lessen these side effects.

Diverticular disease

Diverticulosis is a condition in which small “pouches” called diverticula develop in the lower intestine. It is one of the most common disorders of the colon in the Western world, with the highest rates in the U.S. and Europe. [17] The risk of developing diverticulosis increases with age (more than half of people over age 60 have diverticula) and is usually silent, not causing noticeable symptoms unless the pouches tear or become inflamed, leading to diverticulitis. Diverticulitis can cause persistent abdominal pain (usually in the lower left side), nausea, vomiting, and fever. Treatment is typically a brief period of no food, drinking liquids only, and antibiotic medications. In severe cases where an abscess or perforation may develop, surgery may be needed. However, most people who develop diverticulosis will not develop diverticulitis, with more recent studies estimating only 5% progressing to diverticulitis. [18]

Research shows that a Westernized diet low in fiber and high in red meat and ultra-processed refined foods is a major contributor. [19-21] An eating pattern such as this can lead to constipation, which over time weakens the colon muscles while increasing pressure when trying to defecate; small pouches can form within these weak spots. It can also lead to an increase in harmful intestinal bacteria, causing inflammation and further increasing the risk of diverticular disease. [17,20]

Large cohort studies show a protective effect of fiber on diverticular disease, particularly fibers from fruits, cereal grains, and vegetables. [22,23] A cohort of more than 43,000 men from the Health Professionals Follow-up Study found a protective effect of dietary fiber from diverticulitis, especially cellulose, a type of insoluble fiber. [24] Cellulose is found in the skins of fruits, leafy vegetables, root vegetables, legumes, and wheat bran. A Nurses’ Health Study following more than 50,000 women found that those with the highest fiber intakes (25 or more grams daily) had a 13% lower risk of diverticulitis than those who ate the least (less than 18 grams daily). [2] The protective effect came especially from fibers from cereal grains and whole fruits, but not fruit juices.

Other factors that increase the risk of diverticular disease are increasing age, smoking, lack of exercise, use of certain medications (NSAIDs, steroids, aspirin, opioids), family history, and history of irritable bowel syndrome. [18]

Should I avoid nuts and seeds with diverticulosis?

If you have diverticulosis, chances are you’ve heard that maybe you should avoid certain foods with small hard-to-digest particles: nuts, seeds, popcorn, corn, and fruits and vegetables with seeds like raspberries, strawberries, cucumber, or tomatoes. The reasoning is that these small undigested food particles might become trapped in the diverticular pouches and become inflamed from bacterial infection, causing the uncomfortable condition called diverticulitis. People who have experienced intense symptoms of diverticulitis often change their diets to avoid these foods in hopes of preventing a recurrence. However, evidence has shown this practice to be more of an urban legend than helping to reduce recurrences, and can deter people from eating foods that may actually help their condition in the future.

Although the role of diet with diverticular disease has long been debated, a high-fiber intake with a focus on whole grains, fruits, and vegetables has been found to have a strong association with decreased risk of diverticular disease and diverticulitis. [18] When it comes to nuts and popcorn, research following more than 47,000 men from the Health Professionals Follow-up Study actually found a lower risk of diverticulitis when eating these foods. [25] Including these foods also did not increase the risk of developing new diverticulosis or diverticular complications.

Bottom Line

There are many types of dietary fibers that come from a range of plant foods. It’s important to not hyperfocus on a particular fiber because of its specific proposed action, as each type offers some level of health benefit. Therefore, eating a wide variety of plant foods like fruits, vegetables, whole grains, legumes, nuts, and seeds to reach the fiber recommendation of 25-35 grams daily best ensures reaping those benefits.

Some tips for increasing fiber intake:

• Eat whole fruits instead of drinking fruit juices.
• Replace white rice, bread, and pasta with minimally processed brown rice and other whole grains like barley, millet, amaranth, farro, and
• Add high-fiber foods to current meals: 1-2 tablespoons of almonds, ground flaxseeds, or chia seeds to cereals; diced vegetables to casseroles, stir-fried dishes, and soups.
• For breakfast, choose cereals that have a whole grain as their first ingredient. Another tip is to look on the Nutrition Facts label and choose cereals with 20% or higher of the Daily Value (DV) for fiber.
• Snack on crunchy raw vegetables or a handful of almonds instead of chips and crackers.
• Substitute beans or legumes for meat two to three times a week in chili and soups.
• If it is difficult to eat enough fiber through food, a fiber supplement such as psyllium or methylcellulose powders or wafers can be used. They can help bulk and soften stool so it is easier to pass. However, fiber supplements are not intended to completely replace high-fiber foods.

References

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11. 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 Feb 1;27(2):538-46.
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Last reviewed April 2022

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Why fiber is needed and how it affects health

Health

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Contributor

Natalya Germanovich

May 20, 2021

Understanding why we need to consume dietary fibers that cannot be digested, how they affect the microbiome and why we should avoid their overabundance in the body

changes the composition of bacteria in the intestine. Experts believe that this will help to learn more about how diet affects the body and why the diet should be enriched with cereals, nuts, legumes, fruits and vegetables [1].

At the moment, according to US research, only 1 in 20 US residents consumes the required amount of fiber daily. Lack of dietary fiber can adversely affect health, reduce immunity and lead to obesity [2].

The material was checked and commented by Zinaida Medvedeva, Executive Director of ANO “Healthy Nutrition”

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What is fiber

Fiber is a general term that applies to any type of soluble or insoluble fiber that is not digested. Despite the fact that the body does not use these substances as fuel, they have a strong impact on health [3].

There are two types of dietary fiber:

• Soluble, that is, those that can be dissolved in water. They help lower blood glucose and cholesterol levels. Foods that contain these substances: oatmeal, nuts, beans, lentils, apples, blueberries.
• Insoluble, which do not dissolve in water. They help food pass through the intestines. Such substances are found, for example, in whole grain bread, brown rice, legumes, carrots, cucumbers and tomatoes.

In addition, dietary fiber helps the body maintain a healthy weight. High fiber foods tend to be lower in calories. In addition, the presence of fiber can slow down the digestive processes in the stomach. As a result, a person experiences a feeling of satiety longer [4].

According to the recommendations of the European Food Safety Authority, an adequate dose of fiber is 25 g per day [5].

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American doctors believe that the daily norm for women is 21–25 g (approximately 5–6 apples) and 30–38 g for men (7–8 apples) [6]. However, much depends on the age and health of the person.

Research on adequate fiber intake for children is limited and somewhat inconsistent.

How Fiber Affects the Microbiome

UC Irvine conducted a small study with 26 participants. For the first week, they all followed their normal diet, after which they were tested. In the second week, they switched to a high-fiber diet, eating approximately 40 g of dietary fiber per day. In the third week, the subjects increased their fiber intake to 50 g. After analyzing the changes in the microbiome, the scientists found that with the new diet, the composition of the gut bacteria of the subjects changed by about 8%. Due to the small number of respondents, this result should be considered preliminary, but now there is reason to believe that due to a change in diet, more organisms that break down dietary fiber may appear in the gastrointestinal tract. They are able to adapt to a healthy diet and better process foods that are low in fat, but rich in vitamins and can strengthen the immune system [7].

In 2018, the American Journal of Clinical Nutrition published a meta-analysis of 64 studies involving more than 2,000 people. According to these data, the presence in the diet of the required amount of fiber led to a greater diversity of the microbiome compared to placebo control groups [8].

How to increase your fiber intake

You shouldn’t change your diet radically. The fact is that a sharp transition to a diet rich in dietary fiber can cause unpleasant side effects. For example, bloating and flatulence.

Excessive fiber intake (more than 70 g per day) can lead to cramping, loss of appetite, nutritional deficiencies, vitamins and minerals (especially calcium, magnesium and zinc because fiber can limit their absorption). Another possible adverse effect is an increased risk of intestinal obstruction [9].

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That’s why it’s best to introduce new foods into your diet gradually, while remembering to drink plenty of water. Then the change in diet will be painless.

One of the leaders in the amount of dietary fiber per 100 g is chia seeds. Due to the high proportions (34.4 g), this product is recommended to be soaked in advance and consumed in small quantities [10].

What foods are high in fiber

Fiber is found in cereals (the less processed, the more fiber), as well as nuts, fruits and vegetables.

Fiber content of products:

• Almonds: 13.3 g
• Dark chocolate: 10. 9g
• Sunflower seeds: 10.3 g
• Bran: 10.1 g
• Peas: 8.3 g
• Lentils: 7.3 g
• Chickpeas: 7g
• Beans: 6.8 g
• Avocado: 6.7 g
• Raspberry: 6.5 g

Zinaida Medvedeva, Executive Director of ANO Healthy Nutrition

According to the Lancet magazine, Russians consume much less fiber than they should. However, we are not far behind other developed countries. It all depends on the region, climatic and cultural characteristics.

Whole grains, one of the sources of fiber, are the most deficient foods in Russian diets, according to a large-scale study of major dietary mistakes published in the European Journal of Epidemiology. A low intake of fruits, nuts and seeds rich in dietary fiber was also recorded.

The main issue of the fiber diet is the state of the microbiome. It began to be studied relatively recently, but it is already clear that the influence of intestinal bacteria on the general condition of a person is enormous. Some even call the microbiome the second brain, as it is directly connected to the brain and affects our psychological and emotional state.

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Increasing your fiber intake looks like a simple, cheap, and effective solution to multiple health problems at once. If you increase your intake of vegetables/fruits/legumes (fresh, frozen, pickled) to the recommended 660 grams per day, you will already get enough fiber.

Given that vegetables and fruits should make up almost 50% of the daily diet, it makes sense to spread their consumption over three meals. In addition, in the metabolism of dietary fiber, in addition to short-chain fatty acids, molecular hydrogen is also formed, which, according to recent data, is an antioxidant. In this regard, the regular intake of vegetables and fruits will protect the body from oxidative stress.

As for the question of what kind of fiber is better to consume – soluble or not, in the latter case, the fibers increase the food mass in the gastrointestinal tract and promote the movement of food. This is important for intestinal motility, but such substances are less metabolized. Soluble fiber helps control metabolism, appetite, and energy intake. Conclusion: it all depends on your individual characteristics.

The benefits of fiber for the body / 6 bonuses for health – an article from the “Benefit or harm” section on Food.ru

All kinds of fiber

Fiber (or dietary fiber) is an important component of a healthy diet. Experts refer it to the class of carbohydrates.

There are two types of fiber: soluble and insoluble. And both bring many benefits to human health.

Insoluble fiber does not dissolve in water. It helps to prevent various kinds of malfunctions in the digestive tract. It is rich in wheat:

Soluble fiber absorbs water, forming a gel-like mass. It improves digestion and can help lower high cholesterol and blood glucose levels. This fiber contains:

• oats, peas, beans, apples, citrus fruits, carrots and barley.

Interesting fact

The amount of soluble and insoluble fiber in different foods is different. To get the maximum benefit for the body, you need to eat more plant foods.

The Benefits of Fiber

A diet rich in fiber is truly beneficial.

Cardiovascular disease is the number one cause of death in the world. Regular fiber intake can help prevent them. In a 2017 review of studies, scientists found that people who had a diet high in fiber had a significantly reduced risk of heart disease.

Scientists think that the “magic” effect of fiber is due to the ability to reduce the level of bad cholesterol in the body.

Fiber foods are low in calories. At the same time, they require a lot of time to assimilate, while providing the body with a long-term energy boost.

If you make a meal with fiber, you will feel full faster with minimal calorie intake. And this will definitely benefit the process of losing weight, which is confirmed by the 2019 study. year, published in The Journal of Nutrition.

Mayo Clinic experts also talk about the benefits of fiber for the body. They concluded that a diet high in it may help avoid bowel problems and colorectal ulcers, and reduce the risk of colon cancer. Such data was published in a 2019 study.

Interesting fact

Hippocrates spoke about the benefits of fiber. He assured that she could prevent diseases of the colon.

Losing weight people often say that it is not so difficult to lose weight as to maintain the gained weight. And fiber can help.

If you regularly include products with it in the menu, you can avoid feeling hungry on a diet and after it, prevent overeating.

Adding fiber to your daily menu may help prevent post-meal blood sugar spikes, which can be beneficial for people with diabetes.

And a 2018 review of studies found that people who enjoy foods high in fiber have a lower risk of developing diabetes. At the same time, scientists note the special benefits of fiber from cereals.

The beneficial bacteria in the human gut feed on dietary fiber, and their population is constantly growing. Many processes in the body depend on them. They reduce general inflammation, slow down the aging process, and generally help a person feel and look better.

So fiber, influencing the microbiome, maintains youth and health.

Important

The fiber does not disappear during cooking. It remains unchanged.

How much fiber is needed for health

Institute of Medicine experts have developed the following guidelines:

• Men under 50 years of age – 38 g per day.

• Men over 50 – 30 g per day.

• Women under 50 – 25 g per day.

• Women over 50 – 21 guards a day.

How to start eating more fiber

Not sure how to get your daily fiber intake? Follow these tips:

1. Add bran to your diet. They can make an excellent company for cottage cheese, fermented baked milk or kefir.