Key takeaways
- A randomized trial in Australia found fewer melanomas in adults assigned to daily sunscreen use.
- A 2019 clinical trial found that sunscreen ingredients can enter the bloodstream when applied heavily over much of the body.
- The study authors state that this finding does not mean people should avoid sunscreen.
What it is
Sunscreens filter ultraviolet radiation, which is a major cause of skin cancer. Research has examined both how well sunscreen protects and how its ingredients behave in the body.
What the evidence says
In a randomized trial (Nambour, Australia), adults who were assigned to daily sunscreen use had fewer melanomas over long-term follow-up than those who used sunscreen at their discretion. In a separate trial of healthy volunteers, researchers found that blood levels of several sunscreen ingredients rose above an FDA screening threshold after repeated heavy application. The authors emphasized that this shows the need for further safety testing, not that sunscreen is unsafe.
What the evidence does not establish
The melanoma trial took place in a largely light-skinned population, so it cannot be applied identically to every skin tone. The absorption study measured blood levels, not health outcomes.
Who may want to pay attention
Everyone benefits from understanding sun protection, including people with deeper skin tones. A dermatologist can advise on products and skin cancer screening.
Sources
- Green AC, Williams GM, Logan V, Strutton GM. Reduced melanoma after regular sunscreen use: randomized trial follow-up. J Clin Oncol. 2011;29(3):257–263. View on PubMed
- Matta MK, Zusterzeel R, Pilli NR, et al. Effect of sunscreen application under maximal use conditions on plasma concentration of sunscreen active ingredients: a randomized clinical trial. JAMA. 2019;321(21):2082–2091. View on PubMed
Last reviewed October 2026. Educational information only, not medical advice. Findings from one study or review do not apply identically to every person or product.