The English word for 生物素 is Biotin. You might also come across its older names, Vitamin B7 or Vitamin H.
Often hailed as the “beauty vitamin,” Biotin has surged in popularity for its purported benefits for hair, skin, and nails. But what exactly is it, how does it work, and who really needs it? This guide will answer all your questions about this essential nutrient.
Biotin is a water-soluble B-vitamin (B7) that acts as a crucial coenzyme in your body. It plays a vital role in converting the food you eat—carbohydrates, fats, and proteins—into energy. In simpler terms, biotin helps your body metabolize and use the nutrients from your diet effectively.
The claims about biotin’s benefits are widespread. Let’s break down the science behind the most common ones:
Hair Health: Strengthening and Growth
Biotin is most famous for its role in supporting healthy hair. A biotin deficiency can lead to hair thinning and loss. For individuals with a confirmed deficiency, supplementing with biotin can significantly improve hair strength, volume, and growth. For those with normal biotin levels, the evidence for dramatic hair growth is less conclusive, but it may still contribute to overall hair quality by supporting the keratin infrastructure (the protein that makes up hair).
Nail Health: Fortifying Brittle Nails
Research has shown that biotin supplements can be effective in increasing nail thickness and reducing splitting and brittleness. Studies indicate that taking biotin over several months can lead to a 25% increase in nail thickness for people with brittle nails.
Skin Health: A Radiant Complexion
Biotin supports the health of your skin by playing a role in fat metabolism. This is important for maintaining healthy skin cell function and oil production. A deficiency can cause a red, scaly skin rash, particularly around the eyes, nose, and mouth. While topical biotin is less common, ensuring adequate intake helps maintain skin’s foundation.
Metabolic Support: The Energy Converter
As a key player in metabolic processes, biotin helps your body’s enzymes break down macronutrients. It aids in:
Pregnancy and Breastfeeding
Biotin is critical for embryonic growth. Mild biotin deficiency is relatively common during pregnancy, so prenatal vitamins typically contain biotin to support both the mother’s health and the baby’s development.
You can maintain healthy biotin levels through a balanced diet. Excellent food sources include:
True biotin deficiency is rare because the daily requirement is relatively low and it’s present in many foods. However, certain groups are more susceptible:
Symptoms of deficiency can include hair loss, a scaly red rash, brittle nails, depression, lethargy, and tingling in the hands and feet.
Dosage:
Biotin supplements are widely available in various strengths, ranging from 10 mcg to 10,000 mcg. The Adequate Intake (AI) for adults is 30 mcg per day. Most people get enough from their diet. High-dose supplements (like 5,000-10,000 mcg) are commonly marketed for hair and nail benefits and are generally considered safe, as biotin is water-soluble and excess is excreted in urine.
Crucial Safety Warning:
Biotin can severely interfere with many common blood tests. High levels of biotin in the blood can cause falsely high or low results in tests for troponin (for heart attacks), thyroid function (TSH), and hormone tests, potentially leading to misdiagnosis.
It is strongly recommended to stop taking biotin supplements at least 3-5 days before any blood tests. Always inform your doctor about all supplements you are taking.
For the average person eating a balanced diet, biotin deficiency is unlikely. Focusing on biotin-rich foods is the best and safest way to maintain adequate levels.
If you are experiencing significant hair loss, brittle nails, or other symptoms of deficiency, consult a healthcare professional first. They can help determine if a deficiency is the root cause and advise if a biotin supplement is right for you. For most, biotin is a safe supplement that can support cosmetic and metabolic health, but it is not a magic bullet and should be used wisely, especially considering its potential to interfere with medical testing.
