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by gojomo 2130 days ago
Important news from the future: use shade not sunscreen whenever possible. And, as long as you're not often getting peeling-levels of sunburn, don't fear the sun, or the feeling of the hot sun, so much.

Sun exposure is sufficiently correlated with so many health benefits that it is almost certainly causative for those benefits – especially lower rates of heart disease. Endogenous Vitamin-D production is just one mechanism/signal of the sun's influence, not the full story, so supplementation of Vitamin-D can't reproduce all the sun's benefits.

And, other than preventing sunburns, the health benefits of sunscreen are suspiciously under-proven, and the potential effects of long-term exposure-to/blood-absorption-of their ingredients under-studied. In another decade or two, the current levels of sunscreen use, and recommendation by expert bodies that should know better, will likely be considered a public health failure up there with "use margarine not butter" or "replace fats with sugars" or "masks don't help against respiratory epidemics".

Use shade not sunscreen whenever possible.

4 comments

I wouldn't be surprised if sunscreen is the next BPA: https://www.cnn.com/2019/05/06/health/sunscreen-bloodstream-...
To help support this, keep an eye on a UV tracker. I used to be terrified of the Australian sun, but with a UV tracker I know when it's safe to be outside for hours with no sunscreen, and when the danger levels are extreme.

https://www.arpansa.gov.au/our-services/monitoring/ultraviol...

I would normally be with you but I burn in just a couple of minutes, and I've unfortunately had some really bad burns in the past (where my skin is still very freckled).

I'm totally with you on shade over sunscreen though, I only put sunscreen on my face, and just try to shade everything else. Sadly my skin hates sunscreen too!

Have you looked into or tried any of the mineral-based sunscreens with zinc oxide or titanium dioxide?
While I agree with many things you said: Unfortunately, any UV light exposure is causing harm not just the exposure leading to sunburn. There is no safe level of tanning. Use the same mental model as with X-Ray exposure.
This isn't a fair analogy since sunlight has many well documented positive effects. Vitamin D production being obvious, but also many understudied effects like nitric oxide release. It's difficult to fully root out confounding effects, but typically people with more sun exposure live for longer, despite having higher rates of skin cancer.
It's very likely the UV is an essential trigger of the benefits of sun exposure – either through supporting chemical processes like internal Vitamin-D synthesis, or simply providing the right amount of chaotic 'eustress' that exercises, without overwhelming, essential self-repair mechanisms. So, I'd strongly disagree that "any UV light exposure is causing harm".

Instead, there's a dose-response curve, as with almost everything else, and some moderate level of UV exposure is almost certainly net-beneficial.

Further, getting a light natural tan from the sun itself, without ever becoming uncomfortably burned, is probably more indicative of that optimal level of UV exposure than remaining ultra-pale from absolute avoidance of all sun-UV.

"There is no safe level of tanning" is misinformation and such confident-but-wrong statements should never be used. It's completely false to state that people shouldn't expose themselves to the sun when it's part of our biology. Overexposure and getting frequent sunburns will add up and increase chances of skin cancer, but to say that no level of sun exposure is safe is wrong.