Biotin (vitamin B7) for fertility

On this page

1. What is biotin?
2. Function and how it works
3. Fertility benefits
4. Recommended daily intake
5. Food sources
6. Cautions and contraindications
7. My Fertility Guide
8. Related pages

1. What is biotin?

Biotin, also known as vitamin B7 or vitamin H, is a water-soluble B vitamin that acts as a coenzyme for several enzymes involved in fat, carbohydrate and amino acid metabolism. It is well known for its role in supporting healthy hair, skin and nails, but it also plays a quieter role in fertility, embryo development and gene expression. Severe biotin deficiency is rare, but subclinical deficiency may be more common in pregnancy.

Reference ranges and recommended intakes vary from country to country — always interpret guidance against the recommendations of your own healthcare authority.

2. Function and how it works

Biotin supports fertility through:

1. Cell metabolism. Biotin is a cofactor for carboxylase enzymes used in fat, carbohydrate and protein metabolism — essential for follicle and embryo development.
2. Gene expression. Biotin supports histone biotinylation, influencing gene expression during early embryogenesis.
3. Hair, skin and nail health. Adequate biotin supports the body tissues that often act as visible markers of wider nutritional status.
4. Glucose regulation. Biotin helps maintain stable blood sugar, relevant in PCOS and metabolic syndrome.

3. Fertility benefits

Biotin is particularly relevant for:

1. Anyone with poor hair, skin or nail quality (often a marker of broader B-vitamin status)
2. Women preparing for pregnancy — biotin demand rises during pregnancy
3. People taking long-term anti-seizure medication (which can deplete biotin)
4. People with frequent antibiotic use (which can deplete biotin-producing gut bacteria)

4. Recommended daily intake

Adequate intake recommendations are around 30 µg per day for adults, rising slightly in pregnancy and lactation. Most preconception multivitamins contain biotin in this range. Higher therapeutic doses (1–5 mg per day) are sometimes used for hair, skin and nail support but are well above what is needed for fertility.

5. Food sources

Biotin is found in:

1. Egg yolks
2. Liver and kidney
3. Salmon and sardines
4. Nuts and seeds (almonds, walnuts, sunflower seeds)
5. Sweet potatoes
6. Mushrooms
7. Whole grains

Note that raw egg whites contain avidin, which binds biotin and prevents absorption — always cook egg whites.

6. Cautions and contraindications

1. Biotin is generally safe at common dietary doses.
2. High-dose biotin (over 5 mg per day) can interfere with thyroid and hormone blood tests, including those used for fertility (FSH, LH, oestradiol, hCG, TSH). Stop biotin supplements at least 72 hours before any blood test.
3. Always consult with a fertility specialist or your doctor before starting any new supplement regime.

7. My Fertility Guide

8. Related pages

• Fertility supplements directory
• Folic acid
• Vitamin B12
• Vitamin B6
• Zinc