Lactose intolerance

Lactose intolerance is a digestive system disorder that occurs when the body cannot digest lactose, a sugar compound found in milk and other dairy products. This happens due to a deficiency or absence of lactase, an enzyme produced in the small intestine that breaks down lactose into simpler sugars that can be absorbed into the bloodstream.

It's worth noting that lactose intolerance is not the same as a milk allergy, as milk allergy is an immune system reaction to the proteins in milk, while lactose intolerance is a digestive disorder caused by a lack of lactase enzyme.

There is no complete cure for lactose intolerance, but it can be managed by limiting or avoiding lactose-containing foods and drinks or taking lactase supplements before consuming them. Many people with lactose intolerance can still consume some dairy products without experiencing symptoms, as different dairy products contain varying amounts of lactose.


There are three types of lactose intolerance:

Primary lactose intolerance

This is the most frequently observed type of lactose intolerance and occurs when the body naturally produces less lactase as a person ages. This type of lactose intolerance usually develops in adulthood, and its severity varies among individuals and populations.

Secondary lactose intolerance

This kind of lactose intolerance occurs due to damage to the small intestine, which impairs lactase production. Conditions like celiac disease, inflammatory bowel disease, or chemotherapy can cause this damage.

Congenital lactose intolerance

This is a rare, genetic form of lactose intolerance in which a baby is born with little or no lactase. This type of lactose intolerance is present right from birth and is usually diagnosed in the first few weeks of life. It is an autosomal recessive condition, meaning that both parents must carry a defective gene for their child to inherit the disease.


The primary cause of lactose intolerance is a deficiency or absence of lactase, an enzyme produced in the small intestine that breaks down lactose into simpler sugar molecules that can be absorbed into the bloodstream.

Several factors can cause lactase deficiency, leading to lactose intolerance, including:

Primary lactase deficiency

This is the most observed cause of lactose intolerance, which occurs due to a natural decrease in lactase production as a person ages. Most people are born with sufficient lactase to digest lactose, but over time, lactase production declines, leading to lactose intolerance.

Secondary lactase deficiency

This occurs due to damage to the small intestine caused by an infection, surgery, or other medical conditions, such as celiac disease or Crohn's disease. This damage can reduce the amount of lactase the small intestine produces, leading to lactose intolerance.

Congenital lactase deficiency

This is a genetic form of lactose intolerance in which a baby is born with little or no lactase. This condition is inherited from both parents who carry a defective gene.


Lactose intolerance is more common in some ethnic groups than others, such as people of African, Asian, Hispanic, and Native American descent.


Symptoms of lactose intolerance can vary in severity and typically occur after consuming dairy products or foods containing lactose. Common symptoms include:

These symptoms can occur within 30 minutes to 2 hours after consuming lactose-containing foods or drinks, depending on the quantity of lactose consumed and the severity of lactose intolerance.

It's important to understand that lactose intolerance is not a food allergy, and the symptoms are not life-threatening. However, they can be uncomfortable and affect a person's quality of life. If you suspect that you have lactose intolerance, it's best to consult a healthcare provider for proper diagnosis and management.


There are several methods that healthcare providers use to diagnose lactose intolerance, including:

Lactose intolerance test

This is the most common test used to diagnose lactose intolerance. The test involves consuming a lactose-rich beverage after fasting for several hours. Blood samples are taken at regular intervals to measure the amount of glucose in the bloodstream. If the lactose is not properly digested, the blood glucose levels will not rise as expected.

Hydrogen breath test

This test analyses the amount of hydrogen gas in a person's breath after they consume a lactose-rich beverage. If a person has lactose intolerance, their breath will contain high levels of hydrogen gas.

Stool acidity test

This test is typically used to diagnose lactose intolerance in young children and infants who may have difficulty with other testing methods. The test measures the amount of acid in the stool after the child has consumed a lactose-containing formula or food. The stool of a child with lactose intolerance is generally more acidic.

It's important to note that self-diagnosis of lactose intolerance is not recommended, as the symptoms of lactose intolerance can be similar to other digestive disorders like inflammatory bowel disease. If you suspect lactose intolerance, it's best to consult a physician for proper diagnosis and management.


The most effective treatment for lactose intolerance is to reduce or eliminate the intake of lactose-containing foods or drinks from the diet. However, this can be challenging since lactose is present in many common foods and drinks, including milk, cheese, yoghurt, ice cream, and some baked goods.

There are several ways to manage lactose intolerance, including:

Lactase supplements

These over-the-counter supplements contain lactase enzymes and can be taken before consuming lactose-containing foods or drinks. The lactase enzymes help to break down the lactose, reducing or eliminating symptoms.

Lactose-reduced or lactose-free products

Many food manufacturers produce lactose-reduced or lactose-free versions of dairy products, such as milk, cheese, and yoghurt.

Dairy substitutes

There are many non-dairy alternatives to milk and other dairy products, such as almond milk, soy milk, and rice milk. These products are naturally lactose-free and can be used as substitutes for dairy in cooking and baking.

Experiment with small portions

Some people with lactose intolerance can tolerate small amounts of lactose without symptoms. Experimenting with small portions of lactose-containing foods or drinks can help to determine the individual's tolerance level.

It's important to note that avoiding lactose-containing foods and drinks can also lead to a lack of calcium and other essential nutrients, which can impact bone and overall health. Therefore, people with lactose intolerance need to work with a healthcare provider to develop a nutrition plan that meets their dietary needs.

Do's And Don'ts

If you have lactose intolerance, there are certain dos and don'ts you should follow to manage your condition effectively. Here are some guidelines:

Do’s Don’ts
Choose lactose-free or low-lactose dairy products Consume large amounts of dairy products
Consider non-dairy alternatives Assume all dairy products are off-limits
Read food labels carefully to avoid lactose intake Ignore your symptoms
Take lactase supplements Confuse milk allergy with lactose intolerance
Incorporate calcium-rich foods into your diet Neglect your nutrient intake

Care at Medicover Hospitals

At Medicover, we have the best team of physicians who work together to provide treatment for lactose intolerance with utmost precision. Our highly skilled healthcare team utilises the latest diagnostic techniques and advanced medical approaches to treat lactose intolerance.

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