Biotin is a water-soluble B vitamin that five carboxylase enzymes need to process fatty acids, glucose and amino acids, and most people get enough from food1.
Helps turn the carbohydrates, fats and proteins in food into energy2.
A cofactor for carboxylases that catalyse key steps in making and using fatty acids1.
Pyruvate carboxylase, one of the five biotin enzymes, works in glucose metabolism1.
Biotin enzymes also handle steps in breaking down amino acids from protein1.
Plays roles in histone modification, gene regulation and cell signalling1.
Gut enzymes break protein-bound biotin down to biocytin, biotinidase releases free biotin, and it is absorbed in the small intestine and mostly stored in the liver1. Avidin in raw egg whites binds biotin and stops it being absorbed; cooking inactivates avidin1.
| Food and serving | Amount |
|---|---|
| Sunflower seeds, roasted, ¼ cup | 2.6 µg |
| Sweet potato, cooked, ½ cup | 2.4 µg |
| Almonds, roasted, ¼ cup | 1.5 µg |
| Spinach, boiled, ½ cup | 0.5 µg |
| Broccoli, fresh, ½ cup | 0.4 µg |
| Cheddar cheese, mild, 1 oz | 0.4 µg |
| Milk, 2%, 1 cup | 0.3 µg |
| Food and serving | Amount |
|---|---|
| Beef liver, cooked, 3 oz | 30.8 µg |
| Egg, whole, cooked | 10.0 µg |
| Salmon, pink, canned in water, 3 oz | 5.0 µg |
| Pork chop, cooked, 3 oz | 3.8 µg |
| Hamburger patty, cooked, 3 oz | 3.8 µg |
| Tuna, canned in water, 3 oz | 0.6 µg |
The biotin content of food varies with plant variety and season, and processing such as canning can lower it1. Amounts per serving from1.
Sold alone, in B-complex products and in some multivitamin/mineral products; free biotin is fully absorbed, even in large doses1.
Cooking denatures avidin, so cooked egg whites no longer block biotin absorption1.
Canning and other processing can reduce the biotin in foods1.
The same reference table draws the reference lines on your charts in Ayuvo. Needs differ in pregnancy and breastfeeding, which are not covered here.
| Age | Women | Men |
|---|---|---|
| 19–30 | 30 mcg | 30 mcg |
| 31–50 | 30 mcg | 30 mcg |
| 51–70 | 30 mcg | 30 mcg |
| 71+ | 30 mcg | 30 mcg |
AI (Adequate Intake) is used when there is not enough evidence for an RDA: an amount assumed to be enough. Per day, for adults1.
Signs like these have many possible causes. They are a reason to talk to a clinician, not to self-treat.
Deficiency is rare, and severe deficiency has never been reported in healthy people eating a normal mixed diet1.
No upper limit is set because there is no evidence biotin is toxic at high intakes, but high-dose supplements can give falsely high or low lab test results1.
Biotin comes in biotin-only products, B-complex supplements and some multivitamin/mineral products, and free biotin from supplements is absorbed completely1.
Often promoted for hair, skin and nails, a claim backed only by a few case reports and small studies1.
Combines biotin with other B vitamins in one product1.
Some multivitamin/mineral products also contain biotin2.
The U.S. Food and Drug Administration has received reports of biotin causing falsely low troponin results3.
Supplements can interact with medicines. Talk to a clinician or pharmacist before you start one, especially at high doses.
The evidence is thin. A few small studies without a placebo group found firmer nails in some people with brittle nails, and case reports describe a rare hair condition in children and rashes in infants improving. There is little evidence that biotin helps hair, skin or nails in healthy people.
Yes. High-dose biotin can interfere with lab tests that use biotin-streptavidin technology, including some thyroid hormone and troponin tests, and give falsely high or low results. Even a single large dose has affected thyroid tests within a day, so tell the person ordering a test about any biotin supplements you take.
Raw egg whites contain avidin, a protein that binds biotin tightly and stops it from being absorbed. Cooking breaks down avidin, and a cooked whole egg is one of the better food sources of biotin.
Food logging does not estimate biotin, so Ayuvo tracks it from supplements you log in Medications, and from Apple Health on iPhone or Health Connect on Android when another app saves it there. Charts by day, week, month and year use the reference lines from this page, personalised by age and sex where they differ. Free, with no account.
Or read the code: Ayuvo is open source
Facts on this page come from these sources, checked on the dates shown. Intake numbers come from Ayuvo's shared reference table, which cites the sources marked for them.
General information, not medical advice. This guide is for healthy adults and does not cover pregnancy, breastfeeding, children or medical conditions. It cannot diagnose or treat anything. Talk to a clinician before starting high-dose supplements, or if you think you may have too little or too much of a nutrient. Spotted an error? Email us.