Vitamin H, also known as biotin, is a water-soluble B-vitamin that plays a crucial role in the metabolism of fats, carbohydrates, and proteins. It helps convert food into energy and is essential for maintaining healthy skin, hair, and nails. Biotin is naturally found in various foods, including eggs, nuts, and whole grains. Deficiency in vitamin H is rare, as it is produced by gut bacteria and is present in many foods. Symptoms of deficiency may include hair loss, skin rashes, and neurological issues. Most people obtain sufficient biotin through a balanced diet, making supplementation unnecessary for most individuals.