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Biotin is a member of the B-complex group of water-soluble vitamins. Water-soluble vitamins are stored in the body in very limited amounts and are excreted through the urine. Biotin is present naturally in a wide variety of foods. It is also made by the bacteria that normally live in our intestines.


Biotin's main function is to help your body's cells produce energy. It does this by working with 4 essential enzymes that break down fat, carbohydrate, and protein to yield energy. Biotin also plays a role in the synthesis and function of DNA.

Recommended Intake

Age GroupAdequate Intake
0-6 months5
7-12 months6
1-3 years8
4-8 years12
9-13 years20
14-18 years25
19+ years30

Biotin Deficiency

A biotin deficiency is rare in healthy people who eat a healthful diet, since we usually get enough from the bacteria living in our digestive tracts.

However, certain conditions and life stages can increase the risk of a deficiency. For example, an enzyme called biotinidase is essential to convert biocytin into biotin. Though both biocytin and biotin are easily absorbed in the small intestines, the body can only use the biotin form. If biotinidase is lacking or not working properly, a biotin deficiency can result.

Some people who may be at risk for a biotin deficiency include the following:

Clinical symptoms of a biotin deficiency include:

Biotin Toxicity

There have been no reports of adverse effects due to eating too much biotin. Maximum dosages have not been established.

Major Food Sources

Biotin can be found in a wide variety of foods including eggs, liver, yeast breads, whole grains, sardines, legumes, and mushrooms.

Common foods and their biotin contents.

FoodServing Size Biotin Content
Egg, cooked1 large13-25
Cheddar cheese1 ounce0.4-2
Salmon3 ounces4-5
Whole Wheat bread1 slice0.02-6
Raspberries1 cup0.2-2

Health Implications

There is some highly preliminary evidence suggesting supplemental biotin can help to reduce blood sugar levels in people with diabetes. Biotin may also reduce the symptoms of diabetic neuropathy, though other supplements have much stronger evidence. Even weaker evidence suggests that biotin supplements can promote healthy nails and eliminate cradle cap, a scaly head rash often found in infants.

Tips for Increasing Your Biotin Intake

To increase your intake of biotin, try the following:


Choose My Plate—US Department of Agriculture

Eat Right—Academy of Nutrition and Dietetics


Dietitians of Canada

Health Canada


Biotin. EBSCO Natural and Alternative Treatments website. Available at: Updated December 15, 2015. Accessed March 3, 2017.

Biotin. Linus Pauling Institute. Oregon State University website. Available at: Updated December 15, 2015. Accessed March 3, 2017.

Biotinidase deficiency. Illinois Department of Public Health website. Available at: Accessed March 3, 2017.

Coretta C, Bowers E, Cox T, et al. Biotin. North Carolina State University website. Available at: Accessed March 3, 2017.

Last reviewed March 2017 by Michael Woods, MD, FAAP  Last Updated: 3/3/2017