Biotin

Biotin, also known as Vitamin B7 or Vitamin H, is a water-soluble B-complex vitamin that serves as an essential micronutrient. It acts as a vital cofactor for carboxylase enzymes involved in fatty acid synthesis, gluconeogenesis, and amino acid metabolism. While naturally found in eggs, nuts, and organ meats, and synthesized by gut microbiota, it is one of the most popular supplements for hair, skin, and nail health.

Biotin functions as a coenzyme for five carboxylases that catalyze critical steps in metabolism. It supports:

• Macronutrient Metabolism: Converting fats, proteins, and carbohydrates into cellular energy (ATP).
• Keratin Infrastructure: Enhancing the infrastructure of keratin, the structural protein in hair and nails.
• Skin Barrier Function: Assisting in the synthesis of fatty acids and ceramides, which are essential for maintaining the skin's moisture barrier and reducing dryness.
• Gene Regulation: Influencing cell signaling and the epigenetic regulation of genes involved in the cell cycle and DNA repair.

Based on 2024-2025 clinical consensus:

• Standard AI: 30 mcg daily for adults is sufficient for general health.
• Nail Health: 2,500 mcg (2.5 mg) daily is the clinically supported dose to increase nail thickness and reduce splitting, typically requiring 3–6 months for results.
• Hair Growth: Effective primarily in cases of deficiency (e.g., postpartum, post-illness, or genetic biotinidase deficiency).
• Metabolic Support: Higher doses (up to 8,000 mcg) are sometimes used in functional medicine for glucose metabolism support.
• Safety Warning: Discontinue use at least 72 hours before laboratory blood tests. High-dose biotin causes clinically significant interference with troponin (heart attack marker), TSH (thyroid), and various hormone assays.