Vitamin C

Vitamin C (ascorbic acid) is an essential water-soluble antioxidant and enzyme cofactor with extensive clinical evidence across multiple domains. It is a mandatory cofactor for hydroxylation reactions in collagen synthesis, carnitine biosynthesis, and catecholamine production. As an antioxidant it regenerates vitamin E and glutathione. High-quality RCTs support reduction of common cold duration (not prevention in general populations, but strong prevention in athletes under heavy training), significant reduction of cortisol and inflammatory markers post-exercise, and synergistic collagen synthesis when taken with collagen peptides. Liposomal formulations achieve near-IV bioavailability.