The recommended daily dosage of biotin is 30 to 100 micrograms for adults and adolescents, states Mayo Clinic. For children, dosage depends upon age. Children who are 7-10 years old take 30 micrograms, 4-6 year olds take 25 micrograms, and newborn up to age 3 take 10 to 20 micrograms.
People need biotin to help produces specific fuels, such as fatty acids and glucose, explains Mayo Clinic. The nutrient is also needed for chemical processes involving amino acids and carbohydrates. Biotin occurs naturally in liver, cauliflower, salmon, carrots, bananas, soy flour, cereals and yeast, though cooking reduces its levels in foods. Over-the-counter biotin supplements are sold, although biotin deficiency is uncommon.