Daily supplementation with hydrolysed collagen and vitamin C for 12 weeks increases hair healthy appearance by 31.9% compared to placebo in adults aged 40-60, but does not significantly increase total hair count.

When you take collagen and vitamin C, your body breaks down the collagen into tiny pieces called peptides. These peptides travel through your blood to the skin on your scalp. There, they tell special cells called fibroblasts to make more collagen, which is a strong protein that gives structure to your scalp and hair. Vitamin C helps the new collagen stick together properly and also protects it from damage. This makes the hair you already have stronger, shinier, and less likely to break, so it looks healthier. But it doesn't make new hairs grow, so the total number of hairs stays the same.