A supplement company claims that taking high-dose antioxidant pills will prevent DNA mutations and therefore cancer. Which critique is most scientifically accurate?

Because antioxidants scavenge radicals in vitro, identical effects are guaranteed in vivo at any dose, so high doses always reduce cancer incidence and are universally recommended.

DNA damage in humans is exclusively caused by free radicals; therefore, removing radicals entirely with supplements will eliminate all mutation-driven disease without exception.

High-dose antioxidants cannot be assumed to prevent DNA mutations in humans; observational correlations do not prove causation, supraphysiologic doses can have pro-oxidant effects, and randomized trials have sometimes failed to show benefit or shown harm.

Supplements that provide plant pigments are superior because they contain mystical compounds that directly rewrite DNA sequences to protective variants.