When does lactose intolerance typically develop. How can lactose intolerance be diagnosed and managed effectively. What are the potential consequences of untreated lactose intolerance.

Understanding Lactose Intolerance: Causes and Prevalence

Lactose intolerance is a common 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 inability stems from a deficiency in lactase, an enzyme produced in the small intestine that breaks down lactose into simpler sugars for absorption.

The prevalence of lactose intolerance varies significantly across different populations:

• Approximately 30 million American adults develop some degree of lactose intolerance by age 20.
• It is more common among adults with Asian, African, or Native American heritage.
• People of northern or western European descent are less likely to be affected, but it can still occur.

Onset of Lactose Intolerance

The age at which lactose intolerance develops can vary depending on several factors:

• In white individuals, it often emerges in children older than 5 years.
• African Americans may experience symptoms as early as age 2.
• Premature babies sometimes have lactose intolerance from birth.
• Full-term infants rarely show signs before the age of 3.

Can lactose intolerance develop suddenly in adulthood. While it’s less common, some adults may experience a gradual decline in lactase production, leading to the onset of symptoms later in life. This can be due to various factors, including genetics, aging, or underlying health conditions affecting the small intestine.

Identifying Lactose Intolerance: Symptoms and Diagnosis

Recognizing the symptoms of lactose intolerance is crucial for proper diagnosis and management. Typical symptoms include:

• Abdominal bloating and cramps
• Diarrhea
• Gas (flatulence)
• Nausea

These symptoms usually occur 30 minutes to 2 hours after consuming dairy products and may be more severe when larger amounts are ingested.

How can lactose intolerance be diagnosed. Several diagnostic methods are available:

1. Lactose-hydrogen breath test
2. Lactose tolerance test
3. Stool pH analysis
4. Lactose challenge test (consuming 25 to 50 grams of lactose in water and assessing symptoms)
5. 1 to 2 week trial of a lactose-free diet

It’s important to note that other gastrointestinal conditions, such as irritable bowel syndrome, may present similar symptoms. Therefore, a proper diagnosis by a healthcare professional is essential.

Managing Lactose Intolerance: Dietary Adjustments and Alternatives

The primary approach to managing lactose intolerance involves modifying one’s diet to reduce or eliminate lactose intake. However, complete avoidance of dairy products is often unnecessary and may lead to nutritional deficiencies.

Tolerable Amounts of Lactose

Many individuals with lactose intolerance can consume small amounts of dairy without experiencing significant symptoms. Generally, up to one-half cup (2 to 4 ounces or 60 to 120 milliliters) of milk at one time can be tolerated. Larger servings exceeding 8 ounces (240 mL) are more likely to cause discomfort.

Dairy Products with Lower Lactose Content

Some dairy products are naturally lower in lactose or easier to digest:

• Buttermilk and certain cheeses
• Fermented milk products like yogurt
• Goat’s milk
• Aged hard cheeses

Lactose-Free Alternatives

For those who need to avoid lactose entirely, several alternatives are available:

• Lactose-free milk and milk products
• Lactase-treated cow’s milk (for older children and adults)
• Soy formulas (for infants under 2 years)
• Soy or rice milk (for toddlers and adults)

Are there supplements to help manage lactose intolerance. Yes, lactase enzyme supplements are available in capsule or chewable tablet form. These can be taken with dairy products to aid in lactose digestion. Additionally, lactase drops can be added to regular milk to reduce its lactose content.

Nutritional Considerations for Lactose-Intolerant Individuals

While managing lactose intolerance, it’s crucial to ensure adequate intake of essential nutrients typically found in dairy products, particularly calcium and vitamin D. The recommended daily calcium intake ranges from 1,000 to 1,500 mg, depending on age and sex.

How can lactose-intolerant individuals meet their calcium needs. Several strategies can help:

• Taking calcium supplements with vitamin D (consult a healthcare provider for appropriate choices)
• Consuming calcium-rich non-dairy foods (leafy greens, oysters, sardines, canned salmon, shrimp, and broccoli)
• Drinking calcium-fortified orange juice

It’s important to note that a diet lacking in dairy products may also lead to deficiencies in riboflavin and protein. Therefore, careful meal planning or supplementation may be necessary to maintain overall nutritional balance.

Potential Complications and When to Seek Medical Advice

While lactose intolerance is generally not dangerous, it can lead to complications if not properly managed. In infants and children, inadequate nutrient intake due to dairy avoidance may result in growth problems or developmental delays.

When should you consult a healthcare provider about lactose intolerance. Seek medical advice if:

• You have an infant younger than 2 or 3 years old showing symptoms of lactose intolerance
• Your child is growing slowly or not gaining weight
• You need information about food substitutes
• Symptoms worsen or do not improve with dietary changes
• New symptoms develop

Healthcare providers can offer personalized advice on managing lactose intolerance and ensuring proper nutrition, particularly for growing children and individuals with complex dietary needs.

Secondary Lactose Intolerance: Causes and Management

While primary lactose intolerance is often genetic and develops over time, secondary lactose intolerance can occur due to various factors affecting the small intestine. This type of lactose intolerance may be temporary or permanent, depending on the underlying cause.

Common Causes of Secondary Lactose Intolerance

• Small intestine surgery
• Infections in the small intestine (more common in children)
• Celiac disease
• Crohn’s disease
• Any illness causing severe diarrhea

Can secondary lactose intolerance be reversed. In some cases, treating the underlying condition may improve or resolve lactose intolerance symptoms. For instance, if the intolerance was caused by a temporary diarrheal illness, lactase enzyme levels may return to normal within a few weeks.

Management strategies for secondary lactose intolerance are similar to those for primary lactose intolerance, focusing on dietary adjustments and potential enzyme supplementation. However, addressing the root cause is crucial for long-term improvement.

Lactose Intolerance in Special Populations

Certain groups may require special consideration when it comes to lactose intolerance:

Infants and Young Children

While rare in full-term infants, lactose intolerance can occur in premature babies. For infants under 2 years, soy-based formulas may be recommended if lactose intolerance is suspected. However, it’s crucial to consult a pediatrician before making any dietary changes, as proper nutrition is vital for growth and development.

Pregnant and Breastfeeding Women

Lactose intolerance during pregnancy or while breastfeeding requires careful management to ensure adequate calcium intake for both mother and child. Calcium-fortified foods, supplements, and lactose-free dairy products can help meet nutritional needs without causing discomfort.

Elderly Individuals

As lactase production may decrease with age, some older adults may develop lactose intolerance later in life. This can complicate efforts to maintain bone health, making it essential to find alternative calcium sources or use lactase supplements.

Future Perspectives: Research and Potential Treatments

While there is currently no cure for lactose intolerance, ongoing research is exploring various avenues for improved management and potential treatments:

• Gene therapy: Scientists are investigating ways to introduce lactase-producing genes into the intestinal cells of lactose-intolerant individuals.
• Probiotics: Certain probiotic strains may help alleviate lactose intolerance symptoms by assisting in lactose breakdown.
• Microbiome modulation: Research is examining how altering the gut microbiome might improve lactose tolerance.
• Personalized enzyme supplements: Development of more effective and tailored lactase supplements is ongoing.

What advancements can we expect in lactose intolerance management. While it’s difficult to predict specific breakthroughs, continued research may lead to more targeted treatments, improved diagnostic methods, and potentially even preventive strategies for those at risk of developing lactose intolerance.

As our understanding of lactose intolerance grows, so too does our ability to manage this common condition effectively. By staying informed about the latest developments and working closely with healthcare providers, individuals with lactose intolerance can maintain a healthy, balanced diet while minimizing discomfort and potential complications.

Lactose intolerance: MedlinePlus Medical Encyclopedia

Lactose is a type of sugar found in milk and other dairy products. An enzyme called lactase is needed by the body to digest lactose.

Lactose intolerance develops when the small intestine does not make enough of this enzyme.

Babies’ bodies make the lactase enzyme so they can digest milk, including breast milk.

• Babies born too early (premature) sometimes have lactose intolerance.
• Children who were born at full term often do not show signs of the problem before they are 3 years old.

Lactose intolerance is very common in adults. It is rarely dangerous. About 30 million American adults have some degree of lactose intolerance by age 20.

• In white people, lactose intolerance often develops in children older than age 5. This is the age when our bodies may stop making lactase.
• In African Americans, the problem can occur as early as age 2.
• The condition is very common among adults with Asian, African, or Native American heritage.
• It is less common in people of northern or western European background, but still may occur.

An illness that involves or injures your small intestine may cause less of the lactase enzyme to be made. Treatment of these illnesses may improve the symptoms of lactose intolerance. These may include:

• Surgery of the small intestine
• Infections in the small intestine (this is most often seen in children)
• Diseases that damage the small intestines, such as celiac disease or Crohn disease
• Any illness that causes diarrhea

Babies may be born with a genetic defect which may make them unable to make any of the lactase enzyme.

Symptoms often occur 30 minutes to 2 hours after having milk products. Symptoms may be worse when you consume large amounts.

Symptoms include:

• Abdominal bloating
• Abdominal cramps
• Diarrhea
• Gas (flatulence)
• Nausea

Other intestinal problems, such as irritable bowel syndrome, may cause the same symptoms as lactose intolerance.

Tests to help diagnose lactose intolerance include:

• Lactose-hydrogen breath test
• Lactose tolerance test
• Stool pH

Another method may be to challenge a patient with 25 to 50 grams of lactose in water. Symptoms are then assessed using a questionnaire.

A 1 to 2 week trial of a completely lactose-free diet is also sometimes tried.

Cutting down your intake of milk products that contain lactose from your diet most often eases symptoms. Also look at food labels for hidden sources of lactose in nonmilk products (including some beers) and avoid these.

Most people with low lactase level can drink up to one half cup of milk at one time (2 to 4 ounces or 60 to 120 milliliters) without having symptoms. Larger servings (more than 8 ounces or 240 mL) may cause problems for people with lactase deficiency.

Milk products that may be easier to digest include:

• Buttermilk and cheeses (these foods contain less lactose than milk)
• Fermented milk products, such as yogurt
• Goat’s milk
• Aged hard cheeses
• Lactose-free milk and milk products
• Lactase-treated cow’s milk for older children and adults
• Soy formulas for infants younger than 2 years
• Soy or rice milk for toddlers

You can add lactase enzymes to regular milk. You can also take these enzymes as capsules or chewable tablets. There are also many lactose-free dairy products available.

Not having milk and other dairy products in your diet can lead to a shortage of calcium, vitamin D, riboflavin, and protein. You need 1,000 to 1,500 mg of calcium each day depending on your age and sex. Some things you can do to get more calcium in your diet are:

• Take calcium supplements with Vitamin D. Talk to your health care provider about which ones to choose.
• Eat foods that have more calcium (such as leafy greens, oysters, sardines, canned salmon, shrimp, and broccoli).
• Drink orange juice with added calcium.

Symptoms most often go away when you remove milk, other dairy products, and other sources of lactose from your diet. Without dietary changes, infants or children may have growth problems.

If the lactose intolerance was caused by a temporary diarrheal illness, levels of lactase enzyme will return to normal within a few weeks.

Contact your provider if:

• 
  You have an infant younger than 2 or 3 years old who has symptoms of lactose intolerance.
• Your child is growing slowly or not gaining weight.
• You or your child has symptoms of lactose intolerance and you need information about food substitutes.
• Your symptoms get worse or do not improve with treatment.
• You develop new symptoms.

There is no known way to prevent lactose intolerance. You can prevent symptoms by avoiding foods with lactose.

Lactase deficiency; Milk intolerance; Disaccharidase deficiency; Dairy product intolerance; Diarrhea – lactose intolerance; Bloating – lactose intolerance

• Diarrhea – what to ask your doctor – child
• Diarrhea – what to ask your health care provider – adult

• Digestive system organs

Höegenauer C, Hammer HF. Maldigestion and malabsorption. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 104.

National Institute of Diabetes and Digestive and Kidney Diseases website. Definition & facts for lactose intolerance. www.niddk.nih.gov/health-information/digestive-diseases/lactose-intolerance/definition-facts. Updated February 2018. Accessed August 26, 2022.

Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 131.

Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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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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.

Lactose intolerance after 30: do adults need milk

Society

September 09, 2019, 06:36 pm

Read 360tv in

Some people find it harder to digest dairy products as they get older. There is an opinion that after 30 years, the enzyme that promotes the digestion of carbohydrates is almost not produced. Is it so?

Young children need lactose-rich foods as their bodies grow. Except in situations where babies have congenital enzyme intolerance.

Many residents of Asian countries have poor lactose digestion from the age of three, while Europeans can eat such products up to 30 years without feeling discomfort. However, conflicting information has been provided in various sources about the age at which the benefits of lactose come to naught or become a cause of health problems.

For understanding: lactase is an enzyme produced in the small intestine. It is needed to digest lactose – milk sugar. If the production of the enzyme for some reason decreases, then the use of dairy products causes discomfort.

From seven and older

In an interview with 360, nutritionist Irina Berezhnaya noted that 50-60% of people develop an adult type of lactase deficiency over the years. Speaking globally, after the age of seven, the production of lactase begins to fade in most of the world’s population. Somewhere in 10% of the world’s population this does not happen, and they can tolerate dairy products until old age. But even this statistics is not completely correct, since individual characteristics must always be taken into account.

There are no clear restrictions. It is believed that it starts to progress from about the age of seven, but if it is genetically determined in both parents, then it can also occur at an earlier date

Irina Berezhnaya.

Nutritionist Elena Ostrovskaya, in a conversation with 360, noted that there is no specific age when a person becomes lactose intolerant. This setting varies from person to person.

“There is no such age. Everyone at different times may begin to deteriorate lactose absorption. This usually happens after 40 years, some earlier, some even in old age, ”she said.

According to the nutritionist, digestion of lactose does become more difficult with age, but not for everyone. If there is a genetic predisposition, then the deterioration of lactose tolerance occurs faster and manifests itself more actively.

If suddenly a person has an intolerance, then plain milk can be replaced with coconut, almond or any other that does not contain this carbohydrate.

The origins of the delusion

Nutritionist Elena Solomatina, in an interview with 360, said that lactose is absorbed worse with age, but there is no definite time when this happens.

Individual. For some, [the body] normally perceives [lactose] all their lives. Depends on the condition of the pancreas and how often a person drinks milk

Elena Solomatina.

But even here there are inconsistencies. It happens that people who constantly drink milk do not experience lactase deficiency. However, for some it is congenital. This is an infrequent occurrence, but in this case, a person cannot tolerate any milk – neither whole, nor sour-milk products.

There is also acquired lactase deficiency, when the enzyme is produced in smaller quantities than in childhood.