Biotin

Also called vitamin B7 or vitamin H

Biotin, a type of vitamin B, may interfere with some laboratory tests such as hormone tests and diagnostic tests for heart problems.

Key points

  1. Biotin is a vitamin that belongs to the group of B vitamins. It is also called vitamin B7 or vitamin H.
  2. Biotin is sold as a single-nutrient supplement and as an ingredient in many multivitamins. It may be found in multivitamins for pregnancy, B-vitamin compounds and dietary supplements promoting hair, skin and nail health.  
  3. Biotin may interfere with some laboratory tests, such as hormone tests and diagnostic tests for heart problems. It may cause either falsely decreased or falsely increased test results, which may lead to an incorrect diagnosis and treatment. 
Biotin may interfere with some laboratory tests
If you are taking multivitamins, including prenatal multivitamins, biotin supplements and dietary supplements for hair, skin and nail growth, let your doctor know, especially if you are having any blood tests. Biotin is also called vitamin B7 or vitamin H.

What is biotin?

Biotin is a vitamin that belongs to the group of B vitamins. Biotin is found in small amounts in many foods such as eggs, milk and bananas. Biotin supplements can be bought from health shops, supermarkets and over the counter from pharmacies. Many multivitamins, including prenatal multivitamins and dietary supplements for hair, skin and nail health, contain biotin. It may be labelled as biotin, vitamin B7 or vitamin H in these products. Biotin is commonly used for hair loss, brittle nails, nerve damage, blood sugar control and many other conditions.

How does biotin work?

Biotin helps to break down fats, carbohydrates and proteins from food in your body to convert them to energy. It’s also used in gene regulation and communication between cells.

Biotin deficiency

There isn't a good laboratory test for detecting low biotin levels, so this condition is usually identified by its symptoms, which include thinning of your hair (frequently with loss of hair color) and red scaly rash around your eyes, nose and mouth. Other symptoms include depression, tiredness, hallucinations and tingling of your arms and legs. You may be more at risk of low biotin levels if you are pregnant, breastfeeding or regularly drink a lot of alcohol. 

Biotin can interfere with some blood tests

The daily adequate intake of biotin for adults is 30 micrograms. This is not high enough to interfere with blood test results.

Intakes of more than 10mg of biotin as a supplement may interfere with some laboratory tests, such as hormone tests and diagnostic tests for heart problems. It may cause either falsely decreased or falsely increased test results, which may lead to an incorrect diagnosis and treatment. The risk of interference is higher in children, people with kidney problems and people taking higher doses of biotin.

If you are taking multivitamins, including prenatal multivitamins, biotin supplements and dietary supplements for hair, skin and nail growth that contain biotin, let your doctor know, especially if you are having any blood tests. You may have to stop your supplement for a few days before the test.   

References

  1. Biotin beware! Medsafe, NZ, September 2019
  2. Biotin Office of Dietary Supplements, National Institutes of Health, US
  3. Biotin Nutrient Reference Values for Australia and NZ, National Health & Medical Research Council, Australia and Ministry of Health, NZ

Reviewed by

Katrina Pace is a New Zealand registered dietitian. As a freelance nutrition, health and wellness writer she specialises in making complex health concepts easy to understand.
Credits: Sandra Ponen, Pharmacist. Reviewed By: Katrina Pace, New Zealand Registered Dietitian Last reviewed: 13 Nov 2019