Can lactose intolerance develop later in life. What causes someone to become lactose intolerant as an adult. How is lactose intolerance diagnosed and managed. Is lactose intolerance the same as a milk allergy.

Understanding Lactose Intolerance: A Common Digestive Issue

Lactose intolerance is a digestive condition that affects millions of people worldwide. It occurs when the body is unable to properly digest lactose, a sugar found in milk and dairy products. This condition can develop at any age, even in individuals who have previously had no issues consuming dairy.

The primary cause of lactose intolerance is a deficiency in lactase, an enzyme produced in the small intestine that breaks down lactose. When lactase levels are insufficient, undigested lactose passes into the colon, where it is fermented by bacteria, leading to various uncomfortable symptoms.

Common Symptoms of Lactose Intolerance

• Bloating
• Abdominal cramps
• Gas
• Nausea
• Diarrhea

These symptoms typically occur within 30 minutes to 2 hours after consuming dairy products.

The Onset of Lactose Intolerance: Why It Can Develop Later in Life

Many people are surprised to discover they’ve become lactose intolerant as adults, especially if they’ve enjoyed dairy products without issues for years. This phenomenon is more common than one might think, and there are several reasons why it can occur.

Primary Lactose Intolerance

Primary lactose intolerance is the most common form of the condition. It’s a natural process where lactase production decreases over time. While all infants produce lactase to digest their mother’s milk, this enzyme production often declines as we age. For some individuals, this decline is more pronounced, leading to lactose intolerance symptoms in adulthood.

Secondary Lactose Intolerance

Secondary lactose intolerance can develop suddenly at any age due to an injury or illness affecting the small intestine. Conditions that may trigger this include:

• Celiac disease
• Crohn’s disease
• Bacterial overgrowth in the small intestine
• Intestinal infections
• Surgeries involving the small intestine

In these cases, treating the underlying condition may help restore lactase production and alleviate lactose intolerance symptoms.

Diagnosing Lactose Intolerance: Medical Tests and Procedures

If you suspect you’ve developed lactose intolerance, it’s essential to consult with a healthcare professional for proper diagnosis. Several tests can confirm lactose intolerance:

Lactose Tolerance Test

This test involves consuming a liquid containing high levels of lactose. Blood samples are then taken at intervals to measure glucose levels. If glucose levels don’t rise, it indicates that lactose isn’t being properly digested and absorbed.

Hydrogen Breath Test

For this test, you’ll drink a lactose-containing liquid, and your breath will be analyzed for hydrogen content. Elevated hydrogen levels suggest that lactose isn’t being fully digested, as undigested lactose in the colon produces hydrogen gas.

Stool Acidity Test

This test is primarily used for infants and children. It measures the amount of acid in the stool, which increases when lactose is not properly digested.

Managing Lactose Intolerance: Dietary Adjustments and Supplements

While there’s no cure for lactose intolerance, various management strategies can help minimize symptoms and maintain a balanced diet:

Dietary Modifications

1. Reduce dairy intake: Gradually decrease consumption of milk, cheese, and other dairy products.
2. Choose lactose-free alternatives: Many dairy products are available in lactose-free versions.
3. Consume dairy with other foods: Eating dairy as part of a meal can slow digestion and reduce symptoms.
4. Opt for aged cheeses: Hard, aged cheeses like cheddar or parmesan contain less lactose.
5. Try fermented dairy: Yogurt and kefir contain beneficial bacteria that may aid lactose digestion.

Lactase Enzyme Supplements

Over-the-counter lactase enzyme supplements can be taken with dairy products to aid in lactose digestion. These supplements provide the enzyme that the body lacks, allowing for easier digestion of lactose.

Nutritional Considerations for Lactose Intolerant Individuals

When eliminating or reducing dairy from your diet, it’s crucial to ensure you’re still getting essential nutrients, particularly calcium and vitamin D. Consider incorporating these non-dairy sources into your diet:

Calcium-Rich Foods

• Leafy green vegetables (spinach, kale, collard greens)
• Fortified plant-based milk alternatives
• Canned fish with soft bones (sardines, salmon)
• Tofu processed with calcium sulfate
• Nuts and seeds (almonds, sesame seeds)

Vitamin D Sources

• Fatty fish (salmon, tuna, mackerel)
• Egg yolks
• Fortified foods (cereals, orange juice)
• Sunlight exposure (with proper sun protection)

Consult with a registered dietitian to ensure your diet meets all nutritional requirements while managing lactose intolerance.

Lactose Intolerance vs. Milk Allergy: Understanding the Difference

It’s important to distinguish between lactose intolerance and a milk allergy, as they are two distinct conditions with different causes and treatments.

Lactose Intolerance

• Digestive issue caused by lack of lactase enzyme
• Symptoms are generally limited to the digestive system
• Can often consume small amounts of dairy without severe reactions
• Not life-threatening

Milk Allergy

• Immune system reaction to milk proteins
• Can cause systemic symptoms, including skin reactions and respiratory issues
• Even small amounts of dairy can trigger severe reactions
• Can be life-threatening (anaphylaxis)

If you’re unsure whether you have lactose intolerance or a milk allergy, consult an allergist for proper diagnosis and management.

The Future of Lactose Intolerance: Research and Innovations

As lactose intolerance affects a significant portion of the global population, researchers are continually exploring new ways to manage and potentially treat this condition. Some promising areas of research include:

Genetic Therapies

Scientists are investigating the possibility of using gene therapy to restore lactase production in the small intestine. While still in early stages, this approach could potentially offer a long-term solution for lactose intolerance.

Microbiome Manipulation

Research is ongoing into the role of gut bacteria in lactose digestion. Some studies suggest that certain probiotics may help alleviate lactose intolerance symptoms by enhancing lactose breakdown in the gut.

Advanced Enzyme Supplements

Efforts are being made to develop more effective and longer-lasting lactase enzyme supplements. These could provide better symptom relief and allow for more flexibility in dairy consumption.

Personalized Nutrition

As our understanding of individual genetic and microbiome profiles improves, there’s potential for more personalized approaches to managing lactose intolerance. This could involve tailored dietary recommendations and targeted interventions based on an individual’s specific lactose tolerance level.

While these research areas show promise, it’s important to note that current management strategies remain the most effective way to deal with lactose intolerance. Always consult with healthcare professionals for the most up-to-date advice on managing your condition.

Living Well with Lactose Intolerance: Tips for Daily Life

Adapting to life with lactose intolerance doesn’t mean you have to completely overhaul your lifestyle. With some simple strategies, you can navigate social situations, dining out, and everyday meal planning with ease:

Reading Food Labels

Become adept at reading food labels to identify hidden sources of lactose. Look out for ingredients like whey, milk solids, and casein, which indicate the presence of milk proteins.

Planning Ahead for Social Events

When attending parties or dining out, don’t hesitate to inquire about ingredients or request lactose-free options. Many restaurants are accommodating to dietary restrictions.

Exploring Dairy Alternatives

Experiment with various plant-based milk alternatives like almond, soy, oat, or coconut milk to find options you enjoy. These can be used in cooking, baking, and as beverage substitutes.

Balancing Nutritional Needs

Work with a nutritionist to ensure you’re meeting all your nutritional needs, especially if you’re eliminating dairy entirely. They can help you create a balanced meal plan that accounts for your lactose intolerance.

Gradual Reintroduction

Some people with lactose intolerance find they can tolerate small amounts of dairy, especially when consumed with other foods. Try gradually reintroducing small quantities of dairy products to determine your personal tolerance level.

Remember, lactose intolerance is a common and manageable condition. With the right approach, you can continue to enjoy a varied and nutritious diet while keeping symptoms at bay.

Mayo Clinic Q and A: Lactose Intolerance Can Develop at Any Age

• By

  Liza Torborg

  June 14, 2016

DEAR MAYO CLINIC: What would cause someone to become lactose-intolerant later in life? I’m in my 40s and have never had an issue with dairy, but, now, I can’t seem to have it without problems. Do I need to see a doctor to be tested for allergies, or should I just avoid dairy?

ANSWER: Lactose intolerance isn’t a true allergy, and it can develop at any age. In some people, lactose intolerance may be triggered by another medical condition, such as Crohn’s disease. In others, it develops without a specific underlying cause. It would be a good idea to have your condition evaluated by your doctor to confirm that what you’re dealing with truly is lactose intolerance.

Lactose intolerance results from a problem with the carbohydrate lactose, a type of sugar found in dairy products. When you eat or drink dairy products, enzymes in your small intestine digest lactose, so the body can make energy. In people with lactose intolerance, a certain enzyme, called lactase, is missing from the body. When those people eat dairy products, the body has no way to break down the lactose. This leads to fermentation of the sugar in the intestines and triggers symptoms, such as diarrhea, nausea, abdominal cramps, bloating and gas.

Sometimes, lactose intolerance develops when the small intestine’s production of lactase decreases after an illness, injury or surgery involving the small intestine. This is called secondary lactose intolerance. Among the diseases associated with this kind of lactose intolerance are celiac disease, bacterial overgrowth and Crohn’s disease. Treatment of the underlying disorder may restore lactase levels and improve symptoms.

More common than secondary lactose intolerance is primary lactose intolerance. People who develop primary lactose intolerance start life making normal levels of lactase — a necessity for infants, who get all their nutrition from milk. As children replace milk with other foods, lactase production normally decreases. It stays high enough, though, to digest the amount of dairy in a typical adult diet. In primary lactose intolerance, lactase production declines below normal at some point for reasons that are unclear. The low amount of lactase then makes milk products difficult to digest and leads to lactose intolerance symptoms.

Your doctor can confirm a diagnosis of lactose intolerance with a clinical test. One that’s often used is a lactose tolerance test. It assesses your body’s reaction to a dose of lactose. After you consume a drink containing lactose, a sample of your blood is taken to measure glucose levels. If your glucose level does not rise, it means your body isn’t properly digesting and absorbing the lactose.

Alternatively, another test called the hydrogen breath test may be used. This test also requires you to consume a drink that contains high levels of lactose. Your doctor next measures the amount of hydrogen in your breath. Normally, very little hydrogen is detectable. However, if your body doesn’t digest the lactose, the fermentation reaction in your colon releases hydrogen and other gases. Your intestines absorb those gases, and you exhale them. Larger-than-normal amounts of hydrogen measured during this test are a sign that your body isn’t fully digesting and absorbing lactose.

If you have lactose intolerance, there isn’t a way to cure it. The most effective way for people with lactose intolerance to get relief from symptoms is to lower the amount of dairy products they eat. You may be able to use dairy products that have reduced levels of lactose or are lactose-free. Some people who have lactose intolerance benefit from taking lactase enzyme supplements, as well.

If test results do not point to lactose intolerance, your doctor may recommend additional tests to check for another condition that could be causing your symptoms, such as a milk allergy, intestinal disorders or other problems within your digestive tract. — Dr. Rohit Divekar, Allergic Diseases, Mayo Clinic, Rochester, Minnesota

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Do you get gas, bloating, or even diarrhea after you eat dairy foods? You may be lactose intolerant. This is when you can’t digest lactose, the type of sugar found in dairy products.

Lactose intolerance isn’t a serious health condition, but symptoms can be uncomfortable. You may have stomach upset or gas about 30 minutes to 2 hours after you eat or drink any dairy food.

Lactose intolerance is caused by low levels of lactase, an enzyme that helps you digest lactose in dairy foods, says Laura Acosta, a registered dietitian at the University of Florida in Gainesville.

“Some people are able to tolerate lactose throughout their lives, but others become more lactose intolerant as they age,” usually caused by your genes, she says. “Some people stop producing lactase, or produce less of it, as they reach adulthood and beyond.”

Lactose intolerance is more common among people of Southeast Asian, East Asian, West African, Native American, Hispanic, or Italian ancestry because they’re more likely to carry the gene mutation that causes the condition, says Vijaya Surampudi, MD, assistant professor of medicine at the University of California, Los Angeles.

“We have the highest amounts of lactase when we are young because as babies, we feed on milk. But we often make less and less lactase as we age,” she says. “About 65% of people may experience lactose intolerance at some point in their lives.”

There’s a wide range of lactose intolerance, with some people having no tolerance for dairy, while others can manage to digest foods like hard cheeses or yogurt, she says.

It’s fairly common to notice the signs of lactose intolerance appear as you get older, says Christine Lee, MD, a gastroenterologist at Cleveland Clinic in Ohio.

“This enzyme production can decrease over time in some people, so most people can experience some degree of lactose intolerance as they get older,” Lee says. You can also become lactose intolerant if you have an illness, infection, or take a medication that affects the bowels or intestines.

These conditions can also cause you to develop lactose intolerance later in life:

• Crohn’s disease
• Ulcerative colitis (UC)
• Celiac disease
• Injury or trauma to your small intestines

Foods. Any dairy foods or drinks can have lactose, so read food labels carefully. These foods or ingredients may trigger symptoms:

• Cheese
• Whey
• Milk by-products
• Dry milk
• Butter
• Curds
• Ice cream
• Heavy cream
• Cottage cheese
• Cheese spreads
• Yogurt

Look for milk in ingredients lists in baked goods, chocolate candies, sauces, instant mashed potatoes, pancakes, or milk-based meal replacement or protein shakes. Even non-dairy coffee creamer or whipped toppings may contain some lactose.

Medications. Some medications like birth control pills or antacid tablets also contain lactose, but these may only cause symptoms in people with severe lactose intolerance. Check the labels of your prescription or OTC medications to see if they contain lactose. Ask your doctor or pharmacist if it’s OK for you to take them.

You may not have to give up all the dairy foods you enjoy if you develop lactose intolerance.

Some people with lactose intolerance may be able to eat or drink small amounts of dairy or switch to skim milk and have fewer symptoms. Some people can eat yogurt because it contains live bacteria cultures that help you produce the lactase enzyme to break down lactose.

“Cheese actually has very little lactose. In general, the harder the cheese, the less lactose it has. So many people with lactose intolerance can still tolerate cheese like Parmesan and Swiss in small amounts. This depends on an individual’s sensitivity,” Acosta says.

Talk to your doctor to identify what’s causing your lactose intolerance so you can make the right changes to your diet, Lee says.

“If it’s due to decreased production of lactase, then you can choose to take lactase tablets or drops, enzymes sold in most grocery stores without a prescription, or buy lactose-free milk products,” she says. Supplements are taken before a meal with dairy to help you digest the lactose.

If your lactose intolerance is due to a bowel disease or other health conditions, treat that illness first, she adds. “Always play it safe and discuss your symptoms with your physician.” Unexplained weight loss, bleeding, anemia, nausea, or vomiting may be signs of a more serious medical condition, not just lactose intolerance, she says.

As you age, you still need to get enough calcium even if you develop lactose intolerance. Calcium helps you maintain strong bones and teeth, and healthy muscles and nerves.

“There are many calcium-rich foods people can eat if they’re avoiding lactose,” says Allie Wergin, a registered dietitian/nutritionist with Mayo Clinic Health System. “These include lactose-free dairy products like Lactaid or Dairy Ease milks, where the lactose is predigested or hydrolyzed. This means the milk protein has already been broken down and is easier to digest.”

Other foods that are good sources of calcium, according to Wergin:

• Calcium-fortified cereals and fruit juices
• Tofu prepared using calcium sulfate
• Canned salmon or sardines with bones
• Plant-based soy, almond, oat, or rice milks
• Leafy green vegetables like spinach, kale, bok choy, or collard greens
• Broccoli
• Almonds
• Beans like garbanzo, kidney, or navy

“We recommend that you get calcium through your diet. There are different calcium supplements, including calcium carbonate, which is best absorbed if you take it with food, and calcium citrate, which you can take with or without food,” Surampudi says. Only take a calcium supplement if your doctor says you need one, she says.

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Lactose intolerance | Symptoms, complications, diagnosis and treatment

People with lactose intolerance are unable to fully digest the lactose in milk. As a result, they develop diarrhea, gas, and bloating after eating or consuming dairy products. The condition, also called lactose malabsorption, is usually harmless, but its symptoms can be uncomfortable. Most people with lactose intolerance can manage the condition without giving up all dairy products.

Lactase deficiency, an enzyme produced in the small intestine, is usually responsible for lactose intolerance. Many people have low lactase levels but can digest dairy products without problems. If you are actually lactose intolerant, lactase deficiency leads to symptoms after you eat dairy products.

Signs and symptoms of lactose intolerance usually begin 30 minutes to two hours after eating or drinking foods containing lactose. General signs and symptoms include:

• Diarrhea
• Nausea and sometimes vomiting
• Abdominal cramps
• Inflate
• Gases

Make an appointment with your doctor if you often experience symptoms of lactose intolerance after eating dairy products, especially if you are worried about getting enough calcium.

Reasons

Lactose intolerance occurs when the small intestine does not produce enough enzyme (lactase) to digest milk sugar (lactose).

Normally, lactase converts milk sugar into two simple sugars, glucose and galactose, which are absorbed into the bloodstream through the intestinal lining.

If you are lactase deficient, the lactose in food moves to the large intestine instead of being processed and absorbed. In the colon, normal bacteria interact with undigested lactose, causing the signs and symptoms of lactose intolerance.

There are three types of lactose intolerance. Various factors cause lactase deficiency underlying each type.

Primary lactose intolerance

This is the most common type of lactose intolerance. People with primary lactose intolerance begin their lives by producing large amounts of lactase, a must for babies who get all their nutrients from milk. As children replace milk with other foods, their lactase production usually decreases but remains high enough to digest the amount of dairy in a normal adult diet.

In primary lactose intolerance, lactase production drops dramatically, making it difficult for adults to digest dairy products. Primary lactose intolerance is genetically determined, which occurs in a significant proportion of people of African, Asian, or Hispanic ancestry. This condition is also common among Mediterranean or South European ancestry.

Secondary lactose intolerance

This form of lactose intolerance occurs when the small intestine reduces its production of lactase after illness, injury, or surgery involving the small intestine. Diseases associated with secondary lactose intolerance include celiac disease, bacterial overgrowth, and Crohn’s disease. Treating the underlying disorder can restore lactase levels and improve symptoms and signs, although this may take some time.

Congenital or developing lactose intolerance

This disorder is passed from generation to generation in a form of inheritance called autosomal recessive. Premature babies may also be lactose intolerant due to insufficient lactase levels.

Factors that may make you or your child more likely to become lactose intolerant, include:

• Growing up. Lactose intolerance usually appears in adulthood. This disease is rare in children and young children.
• Ethnos. Lactose intolerance is most common in African, Asian, Hispanic, and American Indian people.
• Premature birth. Babies born prematurely may have low lactase levels because the small intestine does not develop lactase-producing cells until late in the third trimester.
• Diseases affecting the small intestine. Small intestinal problems that can cause lactose intolerance include bacterial overgrowth, celiac disease, and Crohn’s disease.
• Some treatments for cancer. If you’ve had radiation therapy for abdominal cancer or intestinal complications from chemotherapy, you’re at increased risk of lactose intolerance.

Lactase deficiency in adults

Lactase deficiency is a violation of the breakdown of lactose due to a deficiency of the lactase enzyme of the small intestine mucosa, accompanied by clinical symptoms.

Lactose is milk sugar. The enzyme that breaks down lactose is called lactase.

Adult-type lactase deficiency develops after a period of breastfeeding. This is due to a gradual decrease in lactase activity with age. After taking dairy products or whole milk, intestinal disorders (diarrhea, flatulence) usually appear. Prevention and treatment consists of following a low-lactose diet or eliminating it completely.

Russian synonyms

Congenital adult lactase deficiency (delayed onset type), primary adult lactase deficiency, hypolactasia, lactose intolerance, lactose malabsorption.

English synonyms

#OMIM 223100, Lactose intolerance, adult type, Hypolactasia, adult type, Disaccharide intolerance III.

Symptoms

Lactase deficiency is characterized by the development of intestinal symptoms after taking milk and dairy products: flatulence, pain and rumbling in the abdomen, diarrhea, bloating. Possible nausea. The stool is liquid or mushy, light yellow in color, with a sour smell.

General information about the disease

Lactase deficiency, or primary lactase deficiency, is a violation of the breakdown of lactose due to a deficiency of the lactase enzyme of the small intestine mucosa, accompanied by clinical symptoms. It is caused by a genetically determined decrease in its production, which manifests itself in the inability to absorb milk sugar (lactose).

Lactase activity manifests itself from the 12-14th week of intrauterine development and reaches its maximum values ​​by the time of birth (at the time of 39-40 weeks). After birth, lactase is produced in large quantities, but by the end of the first year of life, its production decreases. This is the primary, or congenital, late-onset lactase deficiency, which is inherited in an autosomal recessive manner.

Non-specific abdominal symptoms (bloating, upset stool, nausea) develop after consumption of foods containing lactose, mainly whole milk and dairy products. But today lactose is added to other foods (for example, meat, confectionery). The pharmaceutical industry also uses it as an excipient.

The severity of hypolactasia symptoms depends on individual physiological characteristics of a person, intestinal microflora, diet, and psychological factors. Conscious avoidance of milk, which is an important source of calcium, can lead to a deficiency of this element and, as a result, to osteoporosis. This should be remembered and compensate for the daily requirement through other foods rich in calcium. This is especially important for postmenopausal women.

Primary lactase deficiency should be distinguished from secondary (acquired), which occurs when the mucous membrane of the small intestine is damaged due to any acute or chronic disease. Such damage is possible with infectious (intestinal infection), immune (intolerance to cow’s milk protein), inflammatory processes in the intestine, atrophic changes (with celiac disease, after a long period of complete parenteral nutrition, etc.).

Also, this disorder should not be confused with congenital lactase deficiency, a rare genetic disorder whose symptoms appear immediately after birth and are associated with the onset of breastfeeding.

There is a genetic diagnosis of late-onset primary lactase deficiency. The MCM6 gene region is one of the important regulatory elements of the lactase gene. The genetic marker MCM6 (C(-13910)T) is associated with lactose intolerance.

Who is at risk?

• Persons with relatives who are intolerant to milk and dairy products.
• Certain ethnic groups. Lactose intolerance is most common in North America, Africa, Southeast Asia (the incidence of lactase deficiency is 70-100%) In the Russian population, lactase deficiency is observed in approximately 16%.
• The condition rarely occurs in the first year of life, the development of lactose intolerance is associated with growing up.

Diagnosis

The diagnosis can be assumed on the basis of genealogical data, results of coprology (increase in starch, fiber, iodophilic microflora, decrease in fecal pH less than 5.5), determination of carbohydrates in feces. The diagnosis uses a hydrogen breath test. The concentration of hydrogen in the exhaled air is determined before and after lactose loading. In patients with lactase deficiency, an increase in the hydrogen content is recorded, which is associated with increased bacterial breakdown of lactose in the colon. That is, lactose, not completely absorbed in the small intestine, reaches the large intestine, where it is broken down by anaerobic microflora.

Important in the diagnosis is molecular genetic testing for predisposition to lactase deficiency. The analysis will help in the differential diagnosis of the causes of lactose malabsorption and in the selection of an appropriate diet.

With severe clinical manifestations, refusal of milk, it is also important to determine the calcium content in the blood serum and urine.

Treatment

Diet therapy: restriction of products containing lactose.

It is possible to prescribe enzyme preparations that break down lactose.

It is allowed to use fermented milk products with a reduced amount of lactose (yogurt, curdled milk), cottage cheese, butter, hard cheeses, as well as lactose-free.

It is important to take into account the possible lack of calcium intake on a dairy-free diet, which is recommended to be compensated by other foods rich in it or medications.

In young children, often lactase deficiency is combined with intolerance to cow’s milk proteins.