Residual Egg White Avidin — Cooking Does Not Fully Destroy the Anti-Nutrients
It is a myth that light cooking completely destroys the avidin.
According to this study, poaching eggs only destroys one third of the avidin while even frying leaves 30 percent of it behind.
This raises the question of whether there is a net nutritional advantage to eating any egg whites at all. Most likely, it depends on the individual person. There is controversy over whether biotin produced in the intestinal tract is absorbed — if intenstinal biotin production is indeed nutritionally important, then people whose intestinal flora are less avid producers of biotin probably need to be more concerned about the potential adverse effects of consuming egg white.