Biotin, sometimes called Vitamin H, is actually one of the B-Vitamins and very important in cell growth and the production and metabolism of fatty acids. The vitamin also plays a role in maintaining blood sugar levels and in the body’s energy cycle. Probably its best-known dietary role is in hair and nail health, as a deficiency in the vitamin can cause hair loss and weak, brittle nails.
A deficiency in biotin is relatively rare, but can occur in those who have had part of their stomachs removed (as in the case of those who have had gastric bypass surgery) and in those who have increased need, such as in pregnancy or with patients who are healing from injuries or wounds. Smoking has also been associated with the breakdown of biotin in women.
Most adults over the age of 19 need about 30 micrograms of biotin a day from dietary sources. Biotin is found in many foods, but in smaller amounts than other B-vitamins. Biotin is relatively heat-stable, but cooking and preserving does lower the amount available to the body.
One large cooked egg contains a significant amount of biotin, primarily found in the yolk. It is interesting to note, however, that raw egg white actually contains an enzyme that binds biotin to a protein called avidin, reducing the ability of the body to absorb the vitamin. Cooking the egg separates the protein from the avidin, making it more bioavailable.
Three ounces of cooked liver contains almost the entire daily requirement for biotin. It is estimated by the Journal of Food Composition Analysis to contain between 27 and 35 micrograms. Since many people are turned off by the taste of liver (and it is fairly high in fat and cholesterol), other protein foods that contain a good amount of biotin are pork, salmon and halibut.
A 100-gram serving, or almost a half of a cup, of soybeans contains 60 micrograms of biotin. Soy milk, however, does not contain the vitamin. For drinking purposes, both cow’s milk and goat’s milk have more biotin per serving.
Both almonds and walnuts are good sources of biotin. For those who consider biotin nutrition for healthy hair and nails, nuts are a good choice because they also contain omega-3 fatty acids, which have been shown to support scalp health and give hair a healthy, shiny appearance.
5. Swiss Chard
This leafy green is an excellent source of biotin, containing about 10.5 micrograms in a one-cup serving. Two other good leafy greens to consider are romaine lettuce and spinach. Leafy greens are also important for hair health, in that they contain vitamins A and C, which are needed to produce sebum which naturally conditions hair.
6. Whole Wheat Bread
One slice of whole wheat bread contains about one to six micrograms of biotin. The vitamin is found in the bran of the wheat, so white bread has considerably less biotin than whole wheat. Yeast, particularly brewer’s yeast, is another significant source of biotin. Oats are another good grain source of biotin.