Biotin is relatively stable when exposed to heat, light, and oxygen. Strongly acidic conditions can, however, denature this vitamin. In raw eggs, biotin is typically bound to a sugar-protein molecule (the glycoprotein called avidin), and cannot be absorbed into the body unless the egg is cooked, allowing the biotin to separate from the avidin protein.
The deficient dietary intake of pantothenic acid (vitamin B5) can contribute to a functional biotin deficiency since B5 works together with biotin in many metabolic situations. Intestinal problems should also be considered as a possible course of biotin deficiency. The connection between biotin and intestinal problems centers on the role of intestinal bacteria. Under appropriate circumstances, bacteria in the large intestine can produce biotin. When intestinal problems create bacterial imbalance, the body is deprived of this alternative source of biotin. Consumption of raw egg whites can also contribute to biotin deficiency since avidin, a glycoprotein substance in egg white, can bind to biotin and prevent its absorption. The cooking of egg whites disables this binding of biotin by avidin.
372.48 g mol−1