Water-soluble vitamins
Vitamin B7 (Biotin)
Hair · skin · nails
Carboxylase cofactor; fatty acid synthesis and gluconeogenesis.
What Vitamin B7 (Biotin) does
Biotin is a cofactor for five carboxylase enzymes that drive gluconeogenesis, fatty-acid synthesis, branched-chain amino-acid catabolism, and odd-chain fatty-acid metabolism. Frank deficiency is rare in adults eating a normal diet because gut bacteria contribute appreciable biotin. The 'hair, skin, nails' marketing claim is heavily oversold for biotin-replete adults — supplemental megadoses (5,000–10,000 mcg, 100×+ the DV) also interfere with troponin, TSH, and many hormone immunoassays, causing dangerous lab-test errors.
Food sources of Vitamin B7 (Biotin)
Approximate Vitamin B7 (Biotin) content per serving. Whole-food intake counts toward your daily total alongside any supplemental dose.
| Food | Serving | Vitamin B7 (Biotin) |
|---|---|---|
| Beef liver (cooked) | 3 oz | 31 mcg |
| Egg (whole, cooked) | 1 large | 10 mcg |
| Cooked salmon | 3 oz | 5 mcg |
| Sunflower seeds | 1 oz | 2.5 mcg |
| Almonds | 1 oz | 1.5 mcg |
| Sweet potato (cooked) | 1/2 cup | 2.5 mcg |
Signs of Vitamin B7 (Biotin) deficiency
- ●Thinning hair, sometimes with loss of color
- ●Scaly red rash around the eyes, nose, mouth
- ●Brittle nails
- ●Neurological: depression, lethargy, paresthesias
Who needs more Vitamin B7 (Biotin)
Groups and situations where Vitamin B7 (Biotin) requirements rise or status commonly runs low:
- ●Long-term raw-egg-white consumption (avidin binds biotin)
- ●Long-term anticonvulsants (phenytoin, carbamazepine)
- ●Inherited biotinidase deficiency (newborn-screened)
- ●Pregnancy — modest increase in turnover
How Vitamin B7 (Biotin) appears on labels
Supplement labels list Vitamin B7 (Biotin) under several names depending on the chemical form used. Any of these on an ingredients panel counts toward your Vitamin B7 (Biotin) intake:
- biotin
- vitamin b7
- vitamin b-7
- vitamin h
- d-biotin
Best supplements for Vitamin B7 (Biotin)
Top-scoring supplements in our catalog that list Vitamin B7 (Biotin) on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Deep dive
For mechanism of action, dosing protocols, evidence grade, and interaction warnings on Vitamin B7 (Biotin), see the full encyclopedia entry:
Biotin encyclopedia entry →Frequently asked questions
What is the daily target for Vitamin B7 (Biotin)?
What foods are highest in Vitamin B7 (Biotin)?
What is the best form of Vitamin B7 (Biotin) to supplement?
What are the signs of Vitamin B7 (Biotin) deficiency?
Who is most at risk for low Vitamin B7 (Biotin)?
Related water-soluble vitamins
Track your full intake
Formulate's free web app aggregates Vitamin B7 (Biotin) (and ~40 other nutrients) across every supplement in your stack — flagging underdoses, overlaps, and upper-limit overshoots in one view.
Track your intake free →Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Targets and upper limits are general adult reference values; individual needs vary by age, sex, pregnancy status, and clinical context.