You probably think about how nutrition affects your internal health and your weight, but eating the right foods can also improve the quality of your skin. “You can look at food as the raw materials for a factory,” says Ian Koo, a naturopathic doctor based in Mississauga, Ont. “The better the quality of the raw materials we have to start with, the greater the chance that we’ll end up with a good durable product.” Here’s what to add to your diet to improve the health of your skin.