Unfortunately, applying collagen to the skin does not beget collagen. There are only a few ingredients that are proven to increase collagen production, and collagen protein isn't one of them. In fact, its molecules are not small enough to pass through the epidermis and into the dermal layers to reproduce the protein. "Collagen will help hold water and hydrate, but you don't need a spa to do it," says Dr. Draelos.
Verdict: Save your money. If you want a topical treatment, get a prescription for tretinoin (Retin-A).