Hair is made of keratin. Keratin is a form of protein. It needs several key amino acids in order to grow. There are several key amino acids that can actually make your hair grow thicker, faster and shinier. Amino acids are most commonly found in meat. Therein lies the origin of the myth that vegetarianism may stunt hair growth. But it is just a myth because the same amino acids found in meat can also be found in many vegetarian foods. There are many vegetarian foods that contain high levels of the amino acids needed for hair growth.