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by nradov 1399 days ago
Regular sunlight exposure is correlated with lower all-cause mortality.

https://doi.org/10.1111/joim.12251

1 comments

True in women according to that study. Also they didn't ask specifically about sun exposure avoidance, they asked things like "Do you go abroad on holiday to swim and sunbathe". People on dialysis don't go abroad and people who can't swim secondary to poor health don't go swimming abroad. A poorly designed study with too many confounders imo.
The point is that for individual lifestyle decisions you can't take a reductionist approach and look at individual factors in isolation. Maybe moderate sunlight exposure causes DNA damage, but so what? Does it actually reduce lifespan (or healthspan)? Probably not, or at least we don't have any reliable evidence that it does.
I agree. I think it's also reductionist to say sun avoidance increases mortality, at least based on the evidence we have.
They controlled for all the big health and lifestyle confounds, as described in the abstract, it was a huge study (1/5 of the female population of southern Sweden), they tracked the subjects for 20 years. Man if that's not good enough for you I don't think anything will be.
My issue with the study wasn't study size or duration, it was the questionarre. People who go to holiday in the mountains or go swimming are probably healthier. They could have just asked about sun exposure "how many days in the past month have you spent more than 2 hours in the sun". Also, why just study women? Did their analysis not pan out when they used men?
They asked four questions that all pertain to sun exposure and weighted them into a single metric. Seemed pretty reasonable to me. You may find interesting a recent article on how academia's stance on the benefits/dangers of sun exposure has changed in the past few decades, including that study specifically, how it was received, and what criticisms and accolades it's received.

https://www.outsideonline.com/health/wellness/sunscreen-sun-...

"Outside online" does not seem like an unbiased source on this issue. Asking four questions that pertain to something does not make a good measure of that something. Agree to disagree on this one.

This is coming from someone who spends a lot of time in the sun. Melanoma was never going to have much of an impact on mortality at the population level, the incidence of high grade melanoma is far too low.

> This is coming from someone who spends a lot of time in the sun.

Is it coming from someone with a lot of experience evaluating the protocols of epidemiological studies? Sunlight (whether too much or too little) affects us in all sorts of poorly-understood ways; that's why it's useful to do a big correlation study instead of just examining melanomas.