In the stereotypical Ozzie and Harriet family of the 1950s, men ruled the roost while women ruled the roast. That's no longer true (if it ever was), but in most households women are still in charge of nutrition. They stock the pantry, plan the menus, and fill the plates. In most households it's a good thing, since the average woman knows more about nutrition than the average man. But when it comes to optimal nutrition, there are differences between the sexes. The differences are subtle, but they may affect a man's health.