What vitamins or supplements actually help skin in men over 40?

The three supplements with the strongest evidence for skin health in men: (1) vitamin C (500–1000 mg/day), essential cofactor in hydroxylation of proline and lysine for collagen triple-helix formation, with deficiency producing measurable collagen synthesis impairment; (2) collagen peptides (10 g/day hydrolyzed collagen), two RCTs show modest but significant improvement in skin elasticity over 8 weeks; (3) omega-3 fatty acids (2g EPA+DHA/day), anti-inflammatory effect on skin, reduces UV sensitivity, and supports skin barrier function (Proksch et al., Skin Pharmacol Physiol, 2014).

Biotin (vitamin B7) at megadoses is heavily marketed for skin, hair, and nails but has no evidence of benefit in non-deficient individuals, and biotin at high doses interferes with thyroid and troponin lab tests, creating false laboratory results that have led to misdiagnosed conditions. Biotin deficiency is rare. Do not take high-dose biotin.

Honesty Scale: Vitamin C for collagen synthesis, Solid (1). Hydrolyzed collagen peptides, Promising (2). Omega-3 for skin barrier and inflammation, Promising (2). High-dose biotin for skin in non-deficient men, Unsupported (5).

What to do: Ensure dietary vitamin C adequacy first (75 mg/day minimum from food). If you want to supplement for skin, 500 mg vitamin C + 10 g hydrolyzed collagen peptides daily is the most evidence-consistent combination. Add omega-3 (2g EPA+DHA) for the systemic anti-inflammatory benefit.

For the full picture, read The Skin Health Deep Dive