Is sunscreen dangerous? An actual scientist weighs in

There's a viral news story going around that claims scientists have found that using sunscreen increases your risk of death. As a redhead, this is relevant to my interests. But it turns out that the paper being cited was vastly misconstrued and wasn't even about sunscreen at all.

Andrew Maynard of the University of Michigan's Risk Science Center rebuts:

The original paper by Lindquist et al. (Avoidance of sun exposure is a risk factor for all-cause mortality: results from the Melanoma in Southern Sweden cohort, 2014, J. Internal Medicine, DOI: 10.1111/joim.12251) recorded mortality rates from all causes in a group of 29,518 Swedish women between the early 1990′s and the early 2010′s, and related these to sun exposure evaluated using four criteria (more on this below).

Overall, 8.6% of the women (2545) died over the course of the 20 year study. What caught the researchers’ attention in particular though was that women who did not actively seek sun exposure were slightly more likely to die. Over a 15 year period, the researchers found that 96% of women who most actively sought sun exposure were still alive, compared to a survival rate of 95% for women who were moderately active in seeking sun exposure, and a survival rate of 93% for those who did not actively seek sun exposure.

The study's authors don't even mention sunscreen in relation to these findings, writes Maynard. Instead, they speculate that the difference in death rates is about finding the right balance between getting enough Vitamin D and not getting so much sun exposure that you up your chances of skin cancer. At higher latitudes (as in Sweden) that can be a fine line.

The survey asked about how frequently respondents sunbathed in the summertime, how frequently they sunbathed in the wintertime, how often they used tanning beds, and how often they went on winter holidays with a goal of swimming and sunbathing. Based on those questions, there could also be socioeconomic factors at play, because wealthier people are generally more healthy and generally have more free time and monetary resources to spend on frequent sunbathing, winter vacations, and tanning beds. I'd also be curious about how much of an overlap there is with people who just generally have a more active lifestyle — another factor that could affect health and survival.

Basically, there's nothing here that proves (or even really suggests) that sunscreen is dangerous.