By now, you probably realize that to rebuild collagen in skin underneath eyes requires a specific Anti Aging Cream that will stimulate the re-growth of collagen itself. These products contain specific natural ingredients that will boost the production of this vital skin protein.First, a little background into the need for the best skin firming Face Cream. As our skin ages, its ability to produce Collagen and Elastin goes down. It's the responsibility of these two proteins to keep the skin elastic and firm. So a reduction in their levels causes the skin to sag and form wrinkles.