Evidence brief · Supplement
Biotin (B7) for Hair/nails (non-deficient)
Evidence grade D — Only helps if deficient
- Overall grade
- Grade D
- Last revised
- 1
- graded outcome
- 0
- references listed
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
1 at grade D — 1 graded row
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Hair/nails (non-deficient)Evidence grade D
Only helps if deficient
Trivialmixed
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Hair/nails (non-deficient) (grade D).
The evidence in words
The verdict
For hair/nails (non-deficient), Biotin (B7) earns evidence grade D (trivial effect, mixed consistency) — the evidence does not support the claim. Only helps if deficient
How it might work
It is a cofactor for carboxylase enzymes; hair/nail benefits appear only when biotin is genuinely lacking.
How to use it
Only needed for deficiency; stop biotin several days before blood tests.
Safety & cautions
Safe, but the lab-test interference is a real clinical hazard — disclose supplementation before testing.
Bottom line
Skip it for hair unless you're deficient — and always tell the lab, because high-dose biotin falsifies thyroid and cardiac tests.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Deficiency only
- Per clinician; stop before blood tests.
Goes with
- Biotin (B7)Read the full Biotin (B7) monographEvidence grade C
Related reading
Entries that share this one's tags or conditions.
- Biotin (B7) for Deficiency-related hair lossEvidence grade B — Reverses itEvidence grade B
- Biotin (B7): dosage and how to take itPer clinician; stop before blood tests.Evidence grade C
- Biotin (B7): side effects, safety & interactionsSafe, but the lab-test interference is a real clinical hazard — disclose supplementation before testing.Evidence grade C
- Aloe Vera for Glycemic control (oral)Evidence grade C — Inner-leaf gelEvidence grade C
Sources
This entry lists no references of its own — it is assembled from the entries it links to, whose sources are on their pages.
Last revised . A grade is this entry's reading of the evidence, not medical advice.