If you should take Biotin for hair growth, dermatologist suggests that you consume 2mg. per day of this Vitamin, but if you are to use it in order to treat hair loss, the dosage should be increased to 3 mg per day. The daily recommended allowance for Biotin is 30 mcg. per day. You can also get Biotin from eating liver, sardines, egg yolk, cauliflower, banana, carrots, beans, mushrooms and other foods rich in this vitamin.