The anti-wrinkle effectiveness of topically applied hyaluronic acid depends on its molecular weight. Hyaluronic acid with different molecular weights is associated with varying rates of percutaneous absorption at the stratum corneum level (the outermost layer of the skin).
At the epidermis level, hyaluronic acid hydrates the skin, improves elasticity, and increases skin firmness. Its water retention capacity results in softer, smoother, and more radiant skin, delays wrinkle formation, and improves existing wrinkles that typically appear with age.
At the dermis level, hyaluronic acid stimulates collagen synthesis and is found at the ends of collagen and elastin fibers, helping maintain their normal conformation. In aged skin, these connections with hyaluronic acid are particularly absent, which can result in fiber disorganization, potentially leading to wrinkles and nasolabial folds.