Vitamins

Biotin — timing, dose & interactions

Coenzyme for carboxylases in fat, carbohydrate and amino-acid metabolism. Marketed for hair and nails, with little evidence outside true deficiency.

Also known as Vitamin B7

Timing

When to take it

Any time. Stop several days before blood tests — high doses distort many lab results.

Dose note. No UL, but doses in the mg range interfere with thyroid, hormone and troponin lab tests.

Interactions

Biotin with other supplements

Safety

Medications & health conditions

CautionThyroid hormone

Biotin distorts thyroid blood tests. High-dose biotin can make thyroid lab results look falsely abnormal, which may lead to a wrong dose change. Stop it several days before tests.

Strong evidence
CriticalBlood test in the next few days

Biotin causes false lab results. High-dose biotin interferes with many immunoassays — including thyroid hormones and troponin (heart attack test). Stop it several days before blood work and tell the lab.

Strong evidence

Buying guide

What to look for on the label

  • Biotin

    • Low doses (30–300 mcg) are enough unless deficient

FAQ

Common questions

When is the best time to take Biotin?

Breakfast. Any time. Stop several days before blood tests — high doses distort many lab results.

Should Biotin be taken with food?

It can be taken with or without food. Any time. Stop several days before blood tests — high doses distort many lab results.

Can you take Biotin with Alpha-Lipoic Acid?

Yes — but long-term high-dose ALA may slightly lower biotin. No action needed at normal doses. Consider a B-complex if you take high-dose ALA long term.

Sources

References

  1. 01NIH Office of Dietary Supplements — Biotin Fact Sheet for Health Professionals