Beauty-from-within supplements are one of the fastest-growing categories in the health market. But between the marketing claims and the reality, there’s often a significant gap. Here’s what the science actually says about supplements for hair, skin and nails.
Biotin (Vitamin B7)
Biotin is the most heavily marketed ingredient in hair, skin and nail supplements. The reality is nuanced. Biotin deficiency — which does cause hair loss, brittle nails and skin problems — is actually very rare in people eating a normal diet. The compelling evidence for biotin supplementation is largely in people who are deficient. Clinical trials in non-deficient populations show much less dramatic results. That said, biotin is water-soluble, safe in high doses, and some people do report subjective improvement. Standard dose: 30–100mcg. High-dose supplements (1000–10,000mcg) are fashionable but unnecessary unless deficient, and high doses interfere with some thyroid and cardiac biomarker blood tests — important to know if you’re having blood tests.
Collagen Peptides
Collagen is the structural protein of skin, accounting for ~75% of its dry weight. As we age, collagen production declines from approximately age 25, contributing to wrinkles, reduced skin elasticity and joint discomfort. Oral collagen peptides have more evidence than they used to — hydrolysed collagen (broken into smaller peptides) is absorbed in the gut and appears to stimulate fibroblast activity, increasing skin collagen density. Studies typically use 2.5–10g daily for 8–12 weeks and show modest but measurable improvements in skin elasticity, hydration, and wrinkle depth. This is one of the more promising cosmetic supplement ingredients. Marine collagen is well absorbed; bovine collagen also common. Vegetarians should note: no plant-based collagen exists; plant supplements support your own collagen synthesis instead.
Silica
Silicon (as orthosilicic acid, e.g. ch-OSA) is a trace mineral involved in collagen cross-linking. Preliminary evidence suggests it may improve hair and nail strength with consistent use. The evidence is less robust than for biotin or collagen but the safety profile is good.
Vitamin C
Vitamin C is the essential cofactor for collagen synthesis — without it, the enzymes that modify procollagen into stable collagen can’t function (deficiency causes scurvy). It’s also a potent antioxidant that protects the skin from UV-induced oxidative damage. Most people with a good diet get sufficient Vitamin C, but supplementing 200–500mg daily is safe and ensures optimal collagen support.
Zinc
Zinc deficiency is a well-established cause of hair loss (telogen effluvium), poor wound healing, brittle nails and skin problems. Supplementing zinc in those who are actually deficient produces rapid, dramatic improvements in hair and nail health. Worth testing for if you have persistent hair loss or fragile nails that don’t respond to other interventions. Avoid exceeding 25mg zinc daily long-term — it can cause copper deficiency with prolonged high-dose use.
Browse Hair, Skin & Nails Vitamins at Huncoat Pharmacy. Related: Everyday Supplements Guide, Bone Health Vitamins.
At Huncoat Pharmacy: Browse hair, skin & nail supplements, Klorane botanical hair care.