High SPF sunscreen provides significant clinical benefit in actual use conditions: SPF 100+ is more effective than SPF 50+

In the 2011 proposed monograph, the US Food and Drug Administration requested additional data stating "there is currently insufficient evidence that there is clinical benefit to the consumer at SPF above 50." In real-world settings, consumers apply sunscreens at densities lower than are used to clinically determine SPF and the linear dependence of SPF to application density is well established. It is hypothesized that a sunscreen with a higher SPF would provide greater in-use efficacy compared with one currently labeled at the proposed maximum of SPF 50+.

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