Vitamin A is the unrivalled and unmatched hero in improving the structure and function of the skin, and should be included in any effective product concept for the care of aging skin. This makes it an essential part of TetCode4. Vitamin A is effective at inhibiting the enzymes that break down precious collagen, which lends the skin volume and elasticity. This means the collagen-building activities prevail, so the skin can breathe a sigh of relief and remain naturally beautiful.