Vitamin C

Vitamin C (ascorbic acid) is a water-soluble vitamin and powerful electron donor, functioning as a cofactor for at least eight enzymatic reactions, including those involved in collagen biosynthesis, carnitine production, and neurotransmitter synthesis. As an antioxidant, it regenerates other antioxidants such as vitamin E and protects cells from oxidative damage. Vitamin C enhances non-heme iron absorption in the gut by reducing ferric iron to its more absorbable ferrous form. It also plays a central role in immune defense by supporting epithelial barrier function, enhancing neutrophil chemotaxis, and stimulating lymphocyte proliferation. While severe deficiency (scurvy) is rare today, suboptimal intake is common and associated with fatigue, impaired wound healing, and increased susceptibility to infections.