Allergy

Lactose Intolerance Test (Genetic) — Determine Lactase Persistence

Lactose intolerance occurs when the body lacks sufficient lactase, the enzyme needed to break down lactose (milk sugar). This genetic test identifies the LCT gene variant that determines whether you produce lactase into adulthood. Unlike breath or blood sugar tests, a genetic test provides a definitive, one-time result that does not depend on recent diet or symptoms.

Why Test Lactose Intolerance Test?

This test is recommended if you experience bloating, gas, diarrhoea, or stomach cramps after consuming dairy, if you want a definitive answer about your ability to digest lactose, or if you need to distinguish lactose intolerance from milk protein allergy or other digestive disorders.

What Do High Lactose Intolerance Test Levels Mean?

A result showing lactase non-persistence (CC genotype at the LCT locus) indicates primary lactose intolerance. Your body produces decreasing amounts of lactase with age, leading to difficulty digesting lactose.

What Do Low Lactose Intolerance Test Levels Mean?

A result showing lactase persistence (CT or TT genotype) means you likely continue to produce lactase into adulthood and can digest lactose normally. Symptoms may be caused by other conditions such as IBS, milk allergy, or SIBO.

Symptoms to Watch For

  • Bloating after consuming dairy products
  • Gas and flatulence
  • Stomach cramps or pain
  • Diarrhoea after milk consumption
  • Nausea after eating dairy

Who Should Get Tested?

  • People with digestive symptoms after consuming dairy
  • Those who want a definitive genetic answer about lactose digestion
  • Individuals who need to distinguish lactose intolerance from milk allergy
  • Anyone with a family history of lactose intolerance

How to Prepare for Your Test

No special preparation is required. No fasting needed. Bring your ID to the sampling location. Bring valid ID to your appointment.

Order Your Blood Test

Test your Lactose Intolerance Test levels with an accredited Swedish laboratory. Results within days, reviewed by Wellth.

Lactose Intolerance Genotype B →

Frequently Asked Questions

Is lactose intolerance the same as milk allergy?
No. Lactose intolerance is an enzyme deficiency affecting lactose digestion, while milk allergy is an immune reaction to milk proteins. They require different tests and management.
Is this a one-time test?
Yes. Since this is a genetic test, your result will not change over time. You only need to take it once.
Can I still eat some dairy if I am lactose intolerant?
Many lactose-intolerant people can tolerate small amounts of dairy, fermented products like yogurt or hard cheese, or dairy consumed with lactase enzyme supplements.
How common is lactose intolerance in Sweden?
Approximately 5-10% of the Swedish population is lactose intolerant, which is relatively low compared to global averages. However, it is more common in people of non-Nordic descent.
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Wellth Team

Wellth

Our content is written and reviewed by Wellth, and fact-checked against peer-reviewed research and current Swedish clinical guidelines.

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Medical Disclaimer

The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.