FIRST, A DEFINITION: Collagen is a protein that makes up 80 percent of the deeper layers of your skin, called the dermis, where it acts like scaffolding to hold up the top layer, keeping it firm and smooth. It’s truly one of the most important elements of youthfulness. Unfortunately, collagen begins to break down in your mid-30s, says Whitney Bowe, M.D., a dermatologist in New York City. So how, then, can you increase your supply? It’s not as simple as applying collagen to the surface of your skin. “The molecular size is too large to penetrate,” Dr. Bowe says. Instead, you need to tell your skin to produce more of it, and you do that with the supplements you take, the foods you eat, and the skin care you…
