Key facts about lactose intolerance

Milk contains the sugar lactose, which most human digestive systems cannot digest.
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What you need to know:

  • Lactose intolerance is an inability to process the sugar found in milk and other dairy products.
  • Most people start to experience symptoms of lactose intolerance as they age.
  • The key to managing this intolerance is to stay away from dairy products.

Do you get bloated and gassy after consuming milk or milk products such as ice-cream and frosted cakes? Do you have to run to the bathroom shortly afterward? If so, you might be lactose intolerant.

Lactose intolerance is a condition that affects many people and can make everyday activities like going to work or school difficult. Here's what you need to know about it.

What is lactose intolerance?

Lactose intolerance is a condition in which a person's digestive system lacks the ability to break down lactose, a type of sugar found in milk and other dairy products.

People with lactose intolerance cannot digest lactose because their small intestine does not make enough of an enzyme called lactase.

Lactase breaks down lactose into two simpler sugars, glucose and galactose, which are then absorbed into the bloodstream. When there is not enough lactase to break down lactose, it passes through the intestine undigested and into the colon, where bacteria ferment it. This can cause gas, bloating, diarrhoea, and abdominal pain. In addition, some patients may experience nausea and vomiting.

While this condition is uncomfortable, it is not dangerous.

Risk factors for lactose intolerance

There are several risk factors for developing lactose intolerance. One of the most significant is ethnicity. People of Asian, Hispanic, Native American and African descents are at a higher risk of lactose intolerance.

Another risk factor is age. Adults are more likely to develop lactose intolerance than children. This is because the body's production of lactase (the enzyme that breaks down lactose) decreases with age.

Other risk factors include having had intestinal surgery or suffering from an intestinal disease such as Crohn's disease Celiac disease.

Finally, some medications, such as antibiotics and the over use of pain medication like ibuprofen,can also temporarily reduce the body's level of lactase and lead to lactose intolerance.

Types of lactose intolerance

There are three types of lactose intolerance: primary, secondary, and congenital. Primary lactose intolerance is the most common, and it develops when the body starts to produce less lactase, the enzyme that breaks down lactose, as you age. Secondary lactose intolerance can occur after an injury, surgery, or illness (such as Celiac and Crohn's disease) that damage the small intestine. The secondary lactose intolerance may be treatable. Congenital lactose intolerance is very rare and is present from birth.

Difference between milk allergy and lactose intolerance

Lactose intolerance is not the same as a milk allergy. A milk allergy is an immune reaction to one or more proteins in milk, and it can cause a range of symptoms, including hives, wheezing, and vomiting. Lactose intolerance, on the other hand, is caused by the body's inability to digest lactose. Symptoms of lactose intolerance include bloating, flatulence, diarrhoea, and abdominal pain.

Diagnosing lactose intolerance

If you think you might be lactose intolerant, the best thing to do is to see a doctor.

Four main tests are used to diagnose lactose intolerance: the hydrogen breath test, the stool acidity test, the lactose tolerance test, and the gene test.

The hydrogen breath test measures the amount of hydrogen in your breath after you consume lactose. The stool acidity test measures the amount of acidic compounds in your stool. This test is mainly done when diagnosing infants and babies.

The lactose tolerance test involves drinking a lactose solution and then measuring your blood sugar levels over time. The gene test looks for changes in the genes responsible for processing lactose. 

Managing the condition

The best way to manage lactose intolerance is to avoid dairy products or consume them in small amounts. There are also many lactose-free and dairy-free products available on the market.

Check food labels for lactose presence. Foods that contain lactose include the following:

  • Cheese
  • Butter
  • Whey

These are only some of the many dairy products that contain lactose. Be sure to check food labels for the presence of lactose before consuming any product. You can also look for products that are labelled "lactose-free" or "dairy-free."

In addition, some medications contain lactose and can affect people with severe lactose intolerance. In that case, let the doctor know that you have lactose intolerance before taking any medication.

It is worth knowing that there are medicines that can help with the symptoms of lactose intolerance. These are called "lactase enzymes'' and can be taken before consuming any food containing lactose. This will help your body to digest lactose more easily.


Lactose intolerance is a manageable condition. One can start adding dairy products to their diet by slowly increasing their consumption. It is also important to check food labels for lactose content. Treatment focuses on managing the symptoms. Alternatively, probiotics may also be used to manage lactose intolerance. However, it is best to speak with a doctor before trying any new probiotic.