Purpose of taking Lactose Intolerance Tests:

Defining Lactose Tolerance:

When your body fails to produce enough lactase, which can break down the lactose component of sugar, it starts gathering in your large intestine, causing symptoms like bloating, stomach cramps, nausea, or, worst-case scenario, diarrhea it is most likely that you’re suffering from lactose intolerance. 

When to get a Lactose intolerance done:

Your doctor is most likely to recommend you get a lactose intolerance test done if you’re suffering from symptoms like nausea, cramps, gastric conditions, bloating, or diarrhea after consumption of milk or any other dairy product. After that, your physician might suggest you avoid having dairy products for some time to see if the symptoms get better before performing other tests. 

Preparing for the lactose intolerance test: 

Your doctor will guide you on how to prepare for the test. For example, you might be asked to abide by some dietary restrictions before the test or to fast for 8 hours before taking the test.

white milk in clear glass bottle

Detecting Lactose Intolerance:

You should visit your general physician if you notice any of these symptoms after having food with lactose, such as milk or other dairy-oriented products. But first, the doctor should verify if you’re suffering from, in fact, lactose intolerance. To do this, physicians conduct a few lactose intolerance tests, which include:

  1. The hydrogen breath test: A prevalent test where the patient is asked to blow in a balloon-like bag after drinking a lactose solution to measure hydrogen levels in their breath. You’re suffering from lactose intolerance if a large amount of hydrogen is detected.
  2. The lactose intolerance test: This method requires the patient to drink a lactose solution like the hydrogen breath test. After two hours of drinking the solution, your blood is taken to the lab for testing sugar levels in your blood. If the glucose level in your blood does not rise, there’s a high chance that you’re suffering from lactose intolerance.
  • The milk tolerance test: Like the lactose intolerance test, this test would also require you to submit a blood sample for testing. However, instead of a lactose solution, you’ll be given a glass of milk ranging around 500 ml, after which the physicians will test your blood sample. Again, if the blood sugar level hasn’t arisen, there’s a chance you’re lactose intolerant. 

Test Results:

Your doctor will discuss the lactose intolerance test results with you. However, remember that results may vary according to the doctor or hospital. If the hydrogen breath test result suggests a rise in the hydrogen level of more than 1 million parts per million in your fasting test, you’re likely lactose intolerant. 

As far as lactose intolerance is concerned, if the blood sugar levels haven’t risen more than 20 ml per mg within two hours of drinking the lactose solution, you may be lactose intolerant. 


It’s best to have all the information regarding the tests for lactose intolerance; a doctor can guide you on what test to take and about the prerequisites of these tests.