Remember that scene from the first Rocky movie where Balboa quaffs a glass full of raw eggs for breakfast? Well, if he did that every morning, he’d have shown up to his fight with Apollo looking quite a bit different than what was shown in the film.
He’d have had noticeable patchy, red, eroded lesions on his face and, also, if his trunks had slipped down, his groin. His eyebrows and eyelashes might have been missing, too, and he wouldn’t have lasted one round because he would’ve been suffering from depression, lethargy, limb numbness, and even hallucinations.
The preceding are all signs of a biotin deficiency, and it’s what can happen if someone has a predilection for eating raw eggs. The problem is that raw egg (specifically, the egg white) contains a chemical named avidin, which binds to biotin, leading to deficiency. However, since avidin is a protein, it denatures when you cook the egg, thus preventing its ability to bind up biotin.
So don’t be like Rocky. Cook your eggs.