Skin & Hair

Trend Check

Popular skin and hair claims, graded against the research. We check the evidence; we do not sell or recommend products.

Biotin for hair: a popular supplement with a hidden lab-test problem

Biotin has helped hair only in people with a deficiency or an underlying condition. In everyone else the evidence is missing — and high doses can distort important blood tests.

15 October 2026 · D · Unsupported

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