Collagen is a type of protein responsible for keeping skin firm and smooth. It is found in everyone's skin, but it does decrease with age, which often leads to loose skin and wrinkles. Fortunately, various collagen products can help gain some of it back so that the skin can keep as much elasticity as possible no matter your age. Alas, not all products on the market are equal. You can locate the best kinds by finding out the types available, their ingredients, and where to find them.