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Biotin Side Effects


Biotin, also called vitamin B7, is a vital nutrient that plays an essential role in many bodily processes. Biotin helps the body break down fats, carbohydrates, and proteins. It also supports cell growth and helps to regulate gene activity and cell signaling. Other benefits include support for the synthesis of fatty acids and the metabolism of amino acids.

Some evidence suggests that biotin may support healthy hair and nail growth. While biotin can be found in some foods, it’s also popular in supplements for men and women. But are there biotin side effects you should be aware of? 

Here’s what you should remember when considering biotin supplements or multivitamins that provide biotin.

What is Biotin?

Biotin is a water-soluble vitamin and essential nutrient found in foods and supplements. While biotin is a B vitamin, it’s sometimes also referred to as “vitamin H,” where some people refer to “H” as in hair.

That’s because biotin is an important cofactor in the growth of keratin, which is found in the hair. Biotin is also referred to as the beauty vitamin because keratin is also important for the skin and nails. 

Studies have examined the role of biotin in hair health, including hair growth, balding, and the look and feel of the hair strands. While the data is not conclusive about the role that biotin places in hair growth, some studies have demonstrates a link between hair loss and a biotin deficiency. Some studies also indicate that biotin may support nail health and growth in individuals with conditions such as brittle nail syndrome.

Biotin Side Effects

If you’re considering starting a biotin supplement but are curious about potential biotin side effects, the Mayo Clinic notes that for most healthy adults, biotin side effects should not be a concern. According to the Mayo Clinic, “No side effects have been reported for biotin in amounts up to 10 milligrams a day.”

Adverse effects have not been reported in sensitive populations, specifically children or older adults. However, high doses of any vitamins may have unforeseen effects that require immediate medical care.

To reduce the rise of side effects, consult with a healthcare professional if you notice any unusual side effects while taking biotin supplements. You may also take a blood test to measure levels of biotin in the body to determine if supplementation would be beneficial.

Biotin Dosing

Although biotin side effects have not been reported in supplement doses under 10 mg/day, the proper dosing will depend on the individual and the reason for taking biotin supplements. If your doctor has recommended or prescribed biotin, following their dosing instructions is essential. If you are taking biotin supplements alone, without a doctor’s recommendation, follow and do not exceed dosing recommendations and directions on the label. 

The average amount of biotin you should consume daily depends on your age and gender. Use the following recommendations as a guide to how much biotin you should get from your diet:

  • Infants 0 – 6 months: 5 mcg
  • Infants 7 – 12 months: 6 mcg
  • Children 1 – 3 years: 8 mcg
  • Children 4 – 8 years: 12 mcg
  • Children 9 – 13 years: 20 mcg
  • Adolescents 14 – 18 years: 25 mcg
  • Adults 19 years and older: 30 mcg
  • Pregnant women: 30 mcg
  • Breastfeeding women: 35 mcg

Biotin supplementation should only help fill nutritional gaps in a healthy diet. They should not be used to prevent or cure a biotin deficiency.

Biotin supplements are considered safe at all levels. Still, talking with your doctor before starting any new supplement is essential. If you are taking biotin supplements with or without a prescription, there are a few things to keep in mind to avoid any potential adverse effects:  

  • Tell your doctor if you’ve ever experienced any unusual rashes or other allergic reactions to biotin or other supplements or medications.
  • Tell your doctor if you have any other allergies (including allergies to foods, dyes, or preservatives)
  • Talk with your doctor about the use of biotin supplements with food, alcohol, or tobacco.

Biotin is an essential cofactor for many biological functions in the body. But if you get too much, you may experience side effects. Using a biotin dietary supplement may be one way of filling gaps in your diet daily, but make sure you are mindful of the potential side effects to feel your best each day. 

Learn more about selecting the best biotin supplement.