Planning on being out a full day under the summer sun as a very pale north European? Slob on all the sunscreen that you can and hide in the shade when possible.
A day out in mid September / mid March when the sun is not looking to murder you? Revel in it. Soak it up. Be a plant.
I do think we also have observation on our side here, as it has been seen for a long time that people with outdoor occupations have lower skin cancer rates than indoor (eg "Occupational sunlight exposure and melanoma in the U.S. Navy", 1990). Why those stories never broke through to the mainstream is an interesting question.
(I know they're out of fashion now, but the paleo community was talking about doing ~10 minutes of direct sun a day almost two decades ago, with strict guidance to avoid burning, roughly based on the above reasons)
Also important to remember evolution operates at a population level, not individual. We are descended from females that were able to survive at least pregnancy and carry the second to term, but it doesn't matter if they die in the second pregnancy. We're descended from males that were able to mate with said females, but they could have died very shortly after mating. So if you follow "what we evolved with" then that's all you're likely to get.
The UV light polymerizes collagen in presence of vitamin B. They did experiments by repairing cornea that way:
https://pmc.ncbi.nlm.nih.gov/articles/PMC3018104/
"The aim of this study is to evaluate the safety and effectiveness of riboflavin-ultraviolet type A (UV-A) light rays induced cross-linking of corneal collagen in improving visual acuity and in stabilizing the progression of keratoconic eyes.
...
The eyes were saturated with riboflavin solution and were subjected for 30 min under UV-A light
...
Cross-linking was safe and an effective therapeutical option for progressive keratoconus."
I think that this is probably one of the reasons why suntanned skin usually looks like it is in better condition mechanically-wise.
Another my favorite Sun exposure related correlation - vitamin D deficiency and autism, as couple studies on Somali immigrant population in Minnesota and Sweden - where such dark skinned population naturally gets very low on vitamin D - showed such correlation as autism rates in that population is higher than back there in Somali (and that would explain the correlation of low sunlight expo.
And my favorite pet theory is that Neanderthals with their large eyes adapted to the Northern latitudes were significantly impaired by spike of UV radiation - getting highly increased rate of early cataract and other eyesight damage - during that thousand years of magnetic field polar swap 40K years ago, and that caused them to lose to the Cro-Magnon who was coming out of Africa with more dark and smaller eyes more adapted to higher UV levels which are natural to Africa.
> Usually we close our eyes in reflex due to intense light from the Sun, but on day of an eclipse, the intensity of sunlight is decreased and we can view the Sun through naked eyes. While we watch a solar eclipse without any protection to our eyes, the ultraviolet rays penetrate our eyes and cause retinal burn, leading to loss of central vision.
[1]: https://www.indiatoday.in/science/story/partial-solar-eclips...
Apparently there has been an sharp rise in people coming in with retinal damage from staring at the sun. They didn't go into details why someone would do that, but reading this on HN I can start to guess.
There's seems to be a concerted effort at making people afraid of the sun. My guess is because the sun fixes a lot of problems, and problems mean profit.
Seriously, take a step back. If spending time in / looking at the sun was dangerous we wouldn't be here.
Aldous Huxley was taken in, unfortunately: https://en.wikipedia.org/wiki/The_Art_of_Seeing
I would guess it's dangerous nonsense, though there are plausible claims that shortsightedness is associated with not spending much time outside as a child so perhaps there's a slight link with something that isn't nonsense.
AFAIK that has nothing to do with the sun but rather with looking at things at a larger distance than at home.
An obvious thing perhaps worth mentioning: if you're shortsighted (or longsighted) then you see better in bright sunlight because the iris closes, giving you greater depth of field, so that might make people think/feel that sunlight "cures" myopia.
(On the other hand, if you have excellent eyesight then you see better in less bright conditions because your vision is being limited by diffraction at the aperture.)
Why not? People are still arguing in 2025 that the vast majority of the world's climate scientists are wrong about climate change, and there are even some who unironically argue that the Earth is flat. Science is dead. Long live "Whatever I want to believe is true and you're all wrong!"
After my mother got it and had a huge chunk taken out of her leg when I was very young, we have had it drilled into our heads that the sun was going to kill us and we needed to cover up and lather in sun screen for even the slightest possibility of sun exposure.
Obviously that didn't help much as many of us still got it anyway, hah!
But yea there are some folks who are terrified of the sun. I personally think 15-20 minutes unfiltered sunlight is good for me, but beyond that I'm looking for the nearest shade or trying to cover up.
I do not get if it’s a massive and long-running marketing campaign that has brainwashed the entire population, if it’s because many living in US and UK have a very white skin tone thus burn easily, or what else. Skin cancer is a fact of life, but for a species that evolved in the sun, I do not believe one bit that sun exposure, which incidentally is linked to many benefits because it’s so bloody normal, is something that can only be dealt with modern technology and we should be deathly afraid of it. Sure, UV radiation can cause mutations, but our immune system has evolved over billions of years to deal with this exact problem.
By all means use sunscreen if you have to spend a lot of time in the sun and risk a very unpleasant sunburn, but I wish someone would explain the Anglo obsession with daily sunscreen routine.
Yeah, most of the time our immune system deals with it, but sometimes it misses one roge cell and you've got cancer. That's why you want to limit your exposure to mutations even if you're somewhat adapted to deal with them.
Then it's a matter of looking at studies and statistics and deciding for yourself. Personally, I'll keep putting on sunscreen, as I sunburn easily ;)
There's always going to be some risk from UV exposure, but as the parent comment points out we're evolved to deal with it and even to rely on it. There's research showing that low amounts of cellular damage is actually beneficial as it triggers cellular repair mechanisms or aptosis of senecent cells. Even here other commenters point out how exposure improved their skin or vision.
However that natural evolved state doesn't include sitting inside all week and then going outside on the weekend and getting completely toasted sunburnt!
Doing that and getting completely sunburnt overwhelms our normal cellular repair mechanism, the immune system response, etc. It's much more likely a rogue cell evades the immune system when it's swamped with such cells.
Personally I avoid sunscreen if possible for short excursions but will use it if going to the pool as I'm indoors more these years and paler.
Is this a thing? Surely DNA damage from UV is dose-dependent, in which case any greater amount of UV results in a greater chance of skin cancer.