Biotin for Hair

An essential B-vitamin crucial for keratin production, the protein that makes up hair.

Also known as: Vitamin B7 • Vitamin H

other Names
Coenzyme R, Vitamin B7
primary Benefits
Strengthens hair and nails, supports metabolism.
common Dose
2,500 - 10,000 mcg (2.5 - 10 mg) daily.
best Form
D-Biotin.
timing
Can be taken anytime.
safety Rating
Very safe, excess is excreted in urine.

Overview

Biotin, or Vitamin B7, is a water-soluble vitamin that plays a vital role in converting food into energy. It is a key cofactor for several carboxylase enzymes involved in fatty acid synthesis, gluconeogenesis, and amino acid metabolism. Its role in amino acid synthesis makes it fundamental for building keratin, the primary structural protein of hair, skin, and nails. While true biotin deficiency is rare, supplementation is popular for improving hair strength and growth.

Key Benefits

Supports Keratin Infrastructure

Biotin is essential for the production of keratin, which can improve hair's structural integrity, reducing brittleness and breakage.

May Increase Hair Growth Rate

In cases of deficiency, biotin supplementation can significantly improve hair growth. For those with normal levels, it may offer a modest boost to the growth cycle.

Improves Nail Health

Biotin is well-documented to increase the thickness and hardness of fingernails, reducing splitting and cracking.

Dosage & How to Take

For hair and nail health, doses typically range from 2,500 to 10,000 mcg (2.5 to 10 mg) per day.

PurposeDoseNotes
General Hair & Nail Support2,500 - 5,000 mcg/dayThis is the most common dosage range found in beauty supplements.
Addressing Biotin Deficiency5,000 - 10,000 mcg/dayHigher doses may be recommended by a healthcare provider if a deficiency is diagnosed.

Best Time to Take

Can be taken at any time of day, with or without food.

With or Without Food

Not required.

Forms & Bioavailability

FormAbsorptionBest ForNotes
D-BiotinHighGeneral supplementation.This is the naturally occurring, biologically active form of biotin.
Biotin in B-ComplexHighOverall metabolic and energy support.Often included in B-complex formulas, which can offer synergistic benefits.

Side Effects & Safety

Common

  • Generally none at recommended doses.

Rare

  • High doses may cause skin rashes or digestive upset in sensitive individuals.
  • Can interfere with certain lab tests (e.g., troponin, thyroid hormones).

Contraindications

  • None, but inform your doctor of high-dose biotin use before any lab work.

Interactions

Anticonvulsant MedicationsLow

Long-term use of anticonvulsants can lower biotin levels.

Raw Egg WhitesModerate

Contain avidin, a protein that binds to biotin and prevents its absorption. Cooking denatures avidin.

Scientific Research

2017Skin Appendage Disorders

A Review of the Use of Biotin for Hair Loss

A 2017 review concluded that biotin supplementation can be beneficial for hair growth in individuals with an underlying biotin deficiency, but evidence is lacking for its use in non-deficient individuals.

Food Sources

Egg yolks
Liver
Salmon
Avocado
Nuts and seeds

Frequently Asked Questions

Medical Disclaimer

This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.