Biotin — Supplements

Water-soluble B vitamin (B7) essential for carboxylase enzymes in fatty acid synthesis and gluconeogenesis.

Overview

Biotin (vitamin B7) is a water-soluble vitamin that serves as a cofactor for five carboxylase enzymes critical for fatty acid synthesis, amino acid catabolism, and gluconeogenesis. While clinical biotin deficiency is rare, supplementation is widely used for hair, skin, and nail health. High-dose biotin (5,000-10,000 mcg) has limited clinical evidence for keratin improvement. Importantly, biotin supplementation can interfere with biotin-based immunoassays, including troponin and thyroid function tests.

Indications

  • Hair, skin, and nail health
  • Biotin deficiency prevention
  • Fatty acid and glucose metabolism support
  • Keratin structure support

Mechanism of Action

Covalently binds to carboxylase enzymes (ACC, PCC, MCC, PC) enabling CO2 transfer reactions

Dosing

CompoundDoseFrequencyNotes
Biotin5,000 mcgOnce dailyDiscontinue 48-72 hours before any blood tests using biotin-based assays

Safety & Contraindications

  • CRITICAL: High-dose biotin interferes with biotin-streptavidin immunoassays (troponin, TSH, free T4)
  • Discontinue biotin 48-72 hours before laboratory testing
  • May cause false-low troponin or false-abnormal thyroid results
  • Generally safe at supplemental doses; no established upper limit