Lactose Intolerant? How to Know If You Are

14 January, 2019
Did you know that you might be lactose intolerant and not even know it? Lactose intolerance doesn't have to be serious, but it can affect your life. Learn about the symptoms and diagnosis.

Do you want to find out if you are lactose intolerant? If so, we suggest you read this article. You will learn about signs, symptoms and tests.

What is Lactose Intolerance?

drinking milk


Humankind’s gradual genetic change has allowed us to keep drinking milk into adulthood. This and other dairy products contain lactose, a type of sugar. However, some people don’t produce enough lactase, the enzyme to digest and absorb lactoseThat’s when lactose intolerance happens. Lactose not digested passes to the colon, where it ferments and causes gas

The consumption of milk, yogurt or ice cream by a lactose intolerant person doesn’t cause serious or irreversible damage to the digestive system. Instead, lactose intolerance causes temporary yet distressing symptoms.

Many people think they have this problem. However, they may have a different condition. They may suffer from excessive bacteria growth, celiac disease or intestinal inflammation.

Most people with the intolerance have primary lactase deficiency. In other words, they can drink a glass of milk (or equivalent milk products) without any symptoms. They can even have dairy with their meals without any bowel issues.

These people have the option of consuming products that are low in lactose. Another alternative for them is to take lactase supplements.

Signs That You May Be Lactose Intolerant

lactose intolerant

Symptoms begin between 30 minutes and 2 hours after eating or drinking foods with lactose. The severity of symptoms depends on the person and the amount of dairy consumed. How much (or little) lactase is present in the stomach also determines their intensity.

If you experience the following, you may be lactose intolerant:

  • Irritation or burning when going to the bathroom
  • Bloating or stomach pain and more gas that lasts for several hours after consuming dairy
  • Foul-smelling stool and flatulence
  • Diarrhea
  • Constipation

In addition, kids and teens who are lactose intolerant often experience nausea and vomiting.

To clarify, these symptoms don’t always mean the person is lactose intolerant. There are other conditions or digestive disorders (especially stomach flu) that can cause these symptoms. A hint that can help is looking at the time they appear. If it’s after eating or drinking milk, yogurt, cheese, ice cream, etc., it’s more likely to be due to lactose intolerance.

In the case of secondary lactase deficiency, the following signs can occur:

  • Noticeable weight loss
  • Redness around the anus
  • Cramps
  • Explosive diarrhea

We recommend reading: How to Make Gluten-Free, Lactose-Free Crackers

Tests to Detect Lactose Intolerance

a woman who is lactose intolerant

Do you think you may have this problem? Then, it’s important that you see a specialist. A professional can diagnose your symptoms.

The most common tests are:

  • Glycemic Response Test

How does the lab perform the test? First, blood is drawn to measure initial glycemia levels. Then an overload of lactose is given: 50 grams every 30 minutes for 2 hours (4 doses). After that, blood is drawn again to measure glucose.

If the measurements are the same, there is something wrong with lactase. However, this test is not very specific. There are other disorders that can alter glycemia. An example is diabetes mellitus.

  • Hydrogen Breath Test

a kid who is lactose intolerant

This is the test doctors order the most often to diagnose lactose intolerance. First, the patient consumes a lactose drink. Then, every 15 minutes, the patient blows into an airtight bag.

When the small bowel can’t digest milk sugar, it moves into the large bowel. The bacteria present there use it as food and produce hydrogen. Therefore, if your breath has a good amount of hydrogen, maybe it’s due to a problem digesting lactose.

  • Small Bowel Biopsy

Doctors use a thin tube called endoscope to perform this test. With it, they reach the small bowel to take tissue samples. Afterward, they send the samples to the lab for analysis. The results reveal the presence or absence of lactase in the small bowel.

Read this too: 5 Food Habits That Can Ruin Your Face

  • Stool Acidity Test

This test is mostly for small children. Because of their young age, other studies can be risky or impractical. It detects lactic and other fatty acids in the stool. Its presence is the result of lactose fermented by bacteria in the colon.

  • Genetic Test

The goal of this test is to detect primary lactose intolerance due to a variant of a gene called MCM6. A blood or saliva sample is all it takes to assess the gene.

Remember lactose intolerance and other digestive conditions share symptoms. If you think you may suffer from this condition, see your doctor.

  • Manual MSD. Intolerancia a la lactosa.
  • MedlinePlus. Intolerancia a la lactosa.
  • MedlinePlus. Pruebas de tolerancia a la lactosa.
  • National Institute of Diabetes and Digestive and Kidney Diseases. Diagnóstico de la intolerancia a la lactosa.
  • MedlinePlus. Biopsia del intestino delgado.