Biotin, or vitamin B-7, is a compound that is involved in the normal metabolism of food in your digestive system. Biotin can be found naturally in small amounts in some foods, especially yeasts, breads, eggs, some meats and a variety of other food items. You can also use biotin as a nutritional supplement for its potential effects on your health and well-being. Too much biotin can cause some side effects. Talk with your doctor about biotin supplements to make sure you are not taking in too much.
Recommended Dietary Intake
According to the Linus Pauling Institute at Oregon State University, the average daily intake of biotin through the normal consumption of food is between 35 and 60 mcg per day. It is recommended that adults acquire about 30 mcg of biotin daily, whereas adolescents and children require less biotin to meet their daily needs. Biotin supplements can be taken to help correct a biotin deficiency, although a deficiency is very rare.
The Linus Pauling Institute states that very high doses of biotin may help treat excessively high fasting blood glucose levels in patients with non-insulin dependent diabetes. Diabetics who used 9,000 mcg a day for one month were able to decrease their fasting blood glucose levels by 45 percent. However, a 2004 study published in "The American Journal of Clinical Nutrition" using 15,000 mcg of biotin daily was not able to replicate these results.
According to the Food and Nutrition Board's dietary reference intake, biotin is non-toxic. The Mayo Clinic states that biotin causes no side effects when taken in doses of 10 mg, or 10,000 mcg, daily. As much as 200,000 mcg of biotin daily has been well-tolerated in patients with hereditary disorders without any side effects. 200,000 mcg, or 200 mg, is well above the daily requirements for human consumption, and consuming that much biotin through food and supplements is highly unlikely.
The Food and Nutrition Board cites several Japanese studies which found that 10 mg of biotin supplementation for every 100 g of body weight in pregnant rats can inhibit fetal growth, potentially causing birth defects. The dosage used on the rats would be the equivalent to about 7 g of biotin for a 154 lb. person. Because of the exceptionally high amount of biotin required to cause these effects in rats, the Food and Nutrition Board decided not to include the results in their recommendation for the tolerable upper intake level for humans.