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> In particular sunbathers enjoy significantly lower rates of heart disease, liver cancer, colon cancer, and neurodegenerative disease.

That’s mildly interesting, but without analysis that controls for confounding causes, I wouldn’t drive lifestyle choices.

Start here to find all the studies:

Is Sunscreen the New Margarine?

https://www.outsideonline.com/2380751/sunscreen-sun-exposure...

Less radical suggestion; wear UPF clothing, avoid the most direct sunlight part of the day; saves the chemicals, saves the reefs, and reduce likelihood of skin cancer.

You’d get burnt in 15 minutes in NZ or AU. Maybe 30 if you’re in shade. Even with best protection (spf 70 and shade), I still get burnt after half day on the water.

At the beginning of spring and summer, I need sunscreen to avoid burning in a surprisingly short amount of time. Later in the season when/if I've accumulated a decent tan I can go without. But I usually am not shirtless and therefore not tanning my upper body, so I need it pretty much no matter what if I go to the beach.

Why do you feel qualified to offer medical advice like this? Are you a medical doctor?

Medical doctors are no more trained to digest scientific evidence than anyone else. Especially when it comes to population epidemiology.

Statistical illiteracy is widespread among medical doctors.[1] There's no reason to trust a doctor to interpret a p-value. For these types of questions you're much better off listening to a data scientist because they have actual training in interpretative statistics.

[1]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3693708/

> Medical doctors are no more trained to digest scientific evidence

It's about understanding and processing this evidence in the broader context of their medical training. You're trying to generalize the results of a study with many shortcomings to say everyone may be better off dealing with increasing their odds of developing malignant melanoma and dealing with its associated mortality risks.

My issues with using this study to give the above advice:

1. The study was Conducted in Sweden, a place with "limited sunshine and a low UV index" which would naturally preclude its population having lower vitamin D levels.

2. The study was also lacking in the ability to "distinguish between the consequences of an unhealthy lifestyle and of avoidance of sun exposure"

3. The study had no data on vitamin D supplementation/levels

Why not just tell people to supplement vitamin D instead?

> Why not just tell people to supplement vitamin D instead?

One very consistent pattern with vitamin D research is that association studies will find a major relationship between serum vitamin D and some health outcome.[1] But an RCT using vitamin D supplementation will find no effect.[2]

That strongly suggests that serum vitamin D, at least as we measure it, is merely proxying for something else. The map is not the territory. There's an X-factor that's related to serum vitamin D, but is not just serum vitamin D. Artificial supplementation doesn't work. Since the vast majority of population vitamin D variance is related to sun exposure, that would strongly suggest that sun exposure is the X-factor that improves health.

[1]https://www.cambridge.org/core/journals/proceedings-of-the-n... [2]https://jamanetwork.com/journals/jamacardiology/article-abst...

The only reasonable conclusion you can draw from the two studies linked is that vitamin D supplementation to increase serum levels does not significantly prevent CVD. I could just as easily hypothesize that the physical activity required to go outside both increases serum vitamin D and lowers CVD risk.

Just to be clear, I agree with your thought that sun exposure probably carries benefits beyond an increase in serum vitamin D based on anecdotal experience... I supplement vitamin D rigorously, but being in the sun just makes me feel better

They linked a study from a medical journal. Are you asking for additional qualifications? Should there be restrictions on who is allowed to share scholarly articles?

You're ignoring the obvious correlation - they aren't healthier because they get more sun, they get more sun because they spend more time walking/biking/whatever outside.

One possibility. But the original study carefully controlled for exercise and lifestyle factors. To corroborative the causal relationship, we also have extensive experimental evidence where UV and/or bright light on skin/eyes directly improves systematic biomarkers associated with longevity[1][2][3]. These improvements occurs independent of vitamin D synthesis.[4]

[1]https://www.sciencedirect.com/science/article/pii/S0022202X1... [2]https://www.sciencedirect.com/science/article/abs/pii/S03785... [3]https://www.hindawi.com/journals/bmri/2016/1934518/ [4]https://academic.oup.com/endo/article/159/5/1992/4931051?log...

This is a somewhat counterintuitive idea that actually makes sense for a lot of people. However I must note that there are those taking medications that increase their skin cancer risk as a side effect. For them the risk calculation may be different.

This is veryregion-specific. If you live in Oceania for instance then UV damage and skin cancer presents a much greater danger than in other places - the ol' ozone hole has made sun protection a lot more important here.

Melanoma rates are almost 3 times higher here than in North America, and we have have strong education surrounding sun protection: https://canceratlas.cancer.org/the-burden/oceania/

If you're in a high UV area and you want to try something like this, use a UV tracker so you can be informed about the risks.

I have a widget on my phone that displays the current level and estimated burn time, and can pull up a graph of estimated & forecast (turns out cloudy days DO generally block a lot of UV).

It's great to be able to get as much skin exposed as possible during the low UV periods for gentle UV exposure, then know when to cover up & sunscreen during the harsh periods.