Why biotin supplements may not boost your hair or nails as promised

Biotin, also known as vitamin B7, plays a key role in keeping the body functioning properly. It supports energy production, nerve health, and even gene regulation. Yet despite its popularity in beauty supplements, experts say there’s little proof it improves hair, skin, or nails for most people. Biotin helps break down food by turning carbohydrates, fats, and proteins into usable energy. It also supports the nervous system and assists in gene function. While a deficiency can cause problems like brittle nails, hair loss, or a scaly rash, such cases are uncommon in the U.S.

Most people get enough biotin naturally from their diet. Rich sources include liver, eggs, salmon, pork, nuts, and seeds. Daily needs vary by age and life stage, ranging from 5 micrograms for infants under six months to 35 micrograms for breastfeeding women. Health authorities note that biotin supplements are rarely necessary. They can also cause mild side effects and may interfere with certain lab tests. Additionally, other medical conditions—not a lack of biotin—often explain hair or nail issues.

While biotin is essential for metabolism and overall health, supplements have not been proven to enhance appearance. A balanced diet typically provides sufficient amounts, and experts caution against unnecessary supplementation. Those concerned about deficiencies or related symptoms should consult a healthcare professional for advice.