Topical products work on the surface. If you want changes that last, you have to feed the system that builds your skin, hair and nails. Here is what the science actually supports.
Four supplements have credible evidence behind them. Collagen peptides at 10 grams a day show measurable improvement in skin elasticity and hydration after eight weeks in placebo-controlled trials. Biotin only helps if you are actually deficient — most people are not — but a B-complex covers your bases for hair and nail growth.
Omega-3s from algae or fish oil reduce dryness and inflammation, which translates to calmer skin within a month. Vitamin D is the quiet one: low levels correlate with thinning hair and dull skin, and most adults in northern climates need 1000–2000 IU a day from October to April. Skip the buzzy adaptogens until you have those four covered.
And remember: a supplement is an addition, not a replacement. Sleep, hydration, and ten minutes of daily movement do more for your skin than any pill ever will — the pills just make the floor higher.
