This is not even remotely surprising to me. I've always been a bit skeptical of "the sun is evil" (and got even more skeptical when I was told I should wear sunblock inside!) and ensure I get 20 minutes full body exposure daily in the summer. Anecdotally, I can tell a general difference in my mood and sleep during periods where I get adequate sun vs. when I'm not (and I supplement vitamin D when I'm not).
While I am a big fan of the scientific method, it is difficult to do studies that don't have lots of confounding variables in this area, so when in doubt, use common sense is my rule. We evolved with the sun, so the most likely probability is we have at least some defense to it, and more than likely we evolved so that at least some exposure has benefit.
A lot of the "sunscreen inside" people are those trying to maximize their visible skin health and beauty. If you don't care about your physical looks, as least above all else, I imagine the trade off to getting regular direct sunlight is well worth it.
But it is fairly intuitive that sunlight's ultraviolet radiation at any strength is going to degrade your skin over long periods of time.
Could you link to studies backing up your claim about 'visible skin health and beauty'?. I have searched for these a lot, but I cannot find thorough literature study type of research about this.
Except for the 'sitting in office all year and then sit in the sun for two weeks straight and get 14 sun burns is not good, so you should use sunscreen' message, which is not very helpful and could conclude also that one 'should expose to sun moderately, e.g. at least an hour a day if possible'.
Photoaging is the term and a quick search yields a few studies. Ex: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8802961/.
And anecdotally, I never used sun screen and was exposed to a lot of sunburns in the Mediterranean climate. My skin is visibly older and more wrinkled than my peers who used skin protections. My back is full of freckles and dermatologist said this is due to sunburn. I guess sunburn doesn’t need a lot of studies to show it’s very damaging to the skin?
That is kind of my point. Sun burn is not good. But without sun burn? The article you sent doesn't make clear whether photoaging always happens, or only on sun burn or other high doses of exposure.
Not sure about studies, but in a recent deep dive into skincare, all the YouTubers I watched considered it a basic fact, so the assumption is definitely prevalent. Studies would most likely be sponsored by skincare companies.
There's also that picture of the trucker that shows the damage the sun did to the left side of his face after 28 years of driving a truck. Google "picture of trucker with sun damage"
Maybe the trick is to spread sun exposure across the body rather than mostly let our limbs and face take most the sun. Protect those areas, but get fuller body sun more often. The parts of my body on the boundary between heavy exposure and no exposure seem relatively okay. They have a slight freckle-ness to them, but arguably acceptable. (I'm not young; time-tested.)
It's surprising this article doesn't significantly mention sunlight's non-UV components, like infrared light. There appears to be increasing evidence to support its ability to influence various processes within the body to positive effect.
MedCram has some easily digestible reviews on the topic:
“The ‘Slip, Slap, Slop’ guidance is appropriate for the descendants of white-skinned north Europeans living in high-UV environments such as Australia, where they have a lot of skin cancer. But it is not appropriate for white-skinned Brits here in Scotland, and it is absolutely inappropriate for dark-skinned Brits, who have made the reverse migration from Africa or India,” says Weller.
Just be aware of latitude differences and the rest is commonsense.
Right, people who have lived natively there have evolved physical coping mechanisms which must be taken into account when they move to other geographical areas. The reverse for "plains" people who move to high altitudes.
Right from the beginning i had felt that the whole Sun Exposure/Skin Cancer/Sunscreen debate was nonsensical without understanding the "original adaptations" of the people involved.
I remember an article which i read a long time ago that posited that all of our modern health/medical dosage "standards" (eg. BMI) are suspect because they were derived from a sample of European Males and hence are not universally applicable across the world. Given what we know today about genetics/epigenetics/adaptation i have always felt that this should be the first thing doctors should consider when treating patients.
Right, people who have lived natively there have evolved physical coping mechanisms which must be taken into account when they move to other geographical areas. The reverse for "plains" people who move to high altitudes.
What coping mechanisms would that be?
Right from the beginning i had felt that the whole Sun Exposure/Skin Cancer/Sunscreen debate was nonsensical without understanding the "original adaptations" of the people involved.
What "original adaptations" are you referring to?
I remember an article which i read a long time ago that posited that all of our modern health/medical dosage "standards" (eg. BMI) are suspect because they were derived from a sample of European Males and hence are not universally applicable across the world. Given what we know today about genetics/epigenetics/adaptation i have always felt that this should be the first thing doctors should consider when treating patients.
How about you give us a reference to this article before paraphrasing from memory?
> What "original adaptations" are you referring to?
That should have been obvious from the context. A people's "native and niche" geographical area in which they evolved to adapt. Eg. Chukchi in the Arctic (tolerance to extreme cold by increased basal metabolic rate and blood pressure), Bajau Freedivers of Indonesia (much larger spleen) etc. More prosaically darker skin as you get closer to the equator and lighter skin as you go away from it.
> How about you give us a reference to this article before paraphrasing from memory?
How about you understand what is meant when i have said "which i read a long time ago"? I myself have been searching for this for a while now but i don't recall the title and hence am unable to find it. However, One very good example of BMI vs. Fat is this video about the epidemic of diabetes in poor countries that aren't overweight where the British and Indian scientists measure their fat content (the wai wai paradox at 7:40) - https://www.youtube.com/watch?v=aGuED1JczbI
Interesting. I've never been that worried, my skin doesn't burn easily even though I'm very fair-skinned and live in Spain and often hike outdoors.
I just hate that SPF stuff on my skin. It makes it sticky and makes me feel dirty. Instead I just try to avoid burning. I do bring some for when it does start but it almost never does. What I do to avoid it works well enough.
What I tend to do is just take the shady side of the road wherever possible and for the rest of the time just not worry too much unless I really feel I start getting burned. I check that by scratching my skin with my nail, once it starts burning it feels sharper. Then I'd put on the lotion. And by the time I get home my skin will be slightly red but not seriously burned. Which is pretty rare because I tend to tan naturally. By the time spring starts I already have a light brown shade and it protects me during summer. Most of the time I don't even burn at all.
What I do think is bad is someone living in a dark nothern country going on holidays for 2 weeks and spending 2 weeks lying on the beach in the full mediterranean sun. Sunblock or not. My ex used to do that and she got totally burned on the first day even with the sunblock and then spent the rest of the weeks complaining :) I used to live in such a country and I was always more careful during holidays.
There are many sunscreens out there, ranging from greasy and sticky, to completely unnoticeable. My go-to sunscreen of choice is Neutrogena Ultra Sheer Dry-Touch. It's sold in most pharmacies in the U.S. It's lightweight and doesn't feel like you have any sunscreen on at all. There's also a mineral version, but I've not tried it.
>My go-to sunscreen of choice is Neutrogena Ultra Sheer Dry-Touch.
Agree, and this is the only brand I've tried that truly crosses the dry-touch threshold. It's a shame that it's more expensive and not commoditized yet (figured it would be by now since it's been on the market for several years).
You should be aware that the oxybenzones in that stuff are killing the coral and leading to reef bleaching. The mineral version is less bad, but still not a good idea if you or your sewage are even vaguely near tropical water.
The more convenient a sunscreen is, the more likely it is to be killing off coral.
EltaMD has a sunblock which uses zinc oxide thats been milled to extremely fine particle which block UV light but are transparent in the visible range. They also use a super high quality carrier cream so it feels nice, like a light face moisturizer.
Zinc oxide doesn’t give that chemical feeling, doesn’t stain clothes/etc, doesn't poison the environment, and is also more effective at blocking broad spectrum UV than the oxybenzones/etc.
I'll just wear light hoodies and sweat pants if I go fishing sometimes my face still gets burned a little because while I don't look at the sun much or get much sun directly to by face because of my hoodie, the sunlight is also reflected off the lake into my face and I often overlook that bit .... I've got a full beard so that blocks most burns now but I've had many really bad burns when I was young 10 to 16 years old . Now I'm 43 and I'm constantly D deficient even on 5000 units daily, if I don't supplement I really feel like crap and get sick more often.
I've always been skeptical of dermatologist insistence that sun exposure is unequivocally bad. It never made sense. If human health and lifespan were so negatively affected by sunlight, we would all be covered in fur, or everyone would be as dark skinned as populations living near the equator.
Like everything else in life, "moderation in all things" is the best rule to follow. If you spend your life getting deep dark tans or don't take sensible precautions against sunburns, expect melanoma. If you avoid sunlight like a cave dweller, expect deficiencies in everything from vitamins to mental health.
> If human health and lifespan were so negatively affected by sunlight, we would all be covered in fur or dark skinned
Evolution doesn't work like that, as long as you procreate you may die at 40 or 120 and genes would not care. Probably a lot more important to get vitamin d from the sun by reducing skin pigmentation when you live near the poles (getting stronger bones and muscles) than slightly reducing your chances of getting skin cancer at 50+ years (most of your peers die a lot sooner of unrelated causes anyways)
No kidding. It seems such an obvious example of industry taking a kernel of truth and blowing it out of proportion to promote a market for themselves. Yes, sunscreen is beneficial in certain situations, but I know some people who slather all their exposed skin with chemicals to "protect" from the sun over the 5 minutes they spend outside while carrying groceries into the house.
Can you elaborate on this? I am always ridiculed because I don't want to put on sunscreen for health reasons but I don't remember what the evidence was.
Someone else recommended "Neutrogena, Ultra Sheer Dry Touch Sunscreen" in this submission, and taking a quick look at the ingredients, it does have some I wouldn't put on my skin:
- Octocrylene (endocrine disruptive + might cause sun allergies)
The article doesn't distinguish between UV, visible, and IR. Red light and infrared have known direct biological effects as well. Could the benefits of sun exposure be due, in part, to red and IR? Vitamin D is UV dependent, but you can probably get some benefits of other wavelengths without UV exposure. However, it is possible that synergy exists among the various biological responses to different wavelengths.
Interesting, the linked paper [0] does show they controlled for physical activity here, since I would assume someone who gets more sun exposure, is outside more.
If they really have controlled for that factor, shouldn't we see similar results from people with sedentary lives, but high UV exposure? (possibly by regular use of tanning beds or the like?) Being prescribed UV exposure is an interesting idea for the future.
I feel like they should prescribe sunlight for prisoners. I was held for 10 years without seeing the sun, and many jails and prisons are built on budgets that don't allow for any sunlight.
Do you mean that your cell didn't have sunlight or that you literally never went outside? I was watching a documentary on ADX Florence, which is known for its maximum-security isolation, and prisoners were allowed one hour outside per day.
Yeah, the ADX guys sued to get that back. They lost it at some point and went years without. I tried to sue, but it is almost impossible to sue for lack of sunlight because you need to employ expert witnesses to even have a chance to prove that lack of sunlight is harmful to your health.
I was held in cells without windows for five years. The other five the cells had windows but were so dirty that practically no sunlight entered. Never went outside. Maybe a total of 10 hours outside in 10 years. The first five years in a facility where they didn't design any outside into it because it was built in the middle of a downtown area and there wasn't space. The other five in a facility that had large outside areas but no staff to organize corralling a whole cellblock of inmates, getting them through the corridors of the buildings to the outside, monitoring them so they didn't escape and then getting them back. That requires a lot of staff, and most jails and prisons are vastly understaffed.
At some point when it is all over I will write about it. I've not been to trial yet - so this 10 years was while unconvicted waiting for trial, which is even more insane. It's not even the worst of it, IMO. When I finally got out I started working for criminal justice charities on various issues, and I started getting harassed by the police. They would literally come and drag me out of my house every single day of the week and arrest me and cuff me behind my back on the street (this is the USA too, not some Third World dictatorship!) and then let me go a few minutes later. Eventually they arrested me and I served another five months simply because I Tweeted about the harassment. There was nothing illegal about it, but a judge in the USA can do whatever he wants, so there you go.
Related, there were some drugs developed to activate melanin production by hooking in to sunlight damage reaponse related pathways, and they do work for light-free tanning. But they were then found to significantly and meangingfully increase libido in men and women, so now there are follow up projects to develop these for erectile dysfunction / low libido. (You probably haven't heard of these because they're all peptides which generally have to be injected without a lot of development work and luck, but the shocking success ofsemaglutide and friends means maybe injection-only peptide lifestyle drugs have a market)
As a general just-so-story rule of thumb to be discounted in the face of evidence to the contrary, stimulus or stress that's a consequence of doing stuff generally acts as a "growth factor" even if it causes slight damage, including exercise, heat and cold shock, and sunlight.
In sunlight you also get lots of red and infrared, and there's quite a bit of research on the benefits of that. To replicate sunlight you'd also need bulbs for those frequencies.
IR light reduces certain types of inflammation, speeds wound healing, protects against macular degeneration.. I'm surprised there isn't more interest in its benefits given what we've found so far.
> Vitamin D is manufactured in our bodies when the UVB rays in sunlight react with a chemical in the skin called 7-dehydrocholesterol. Bone and muscle cells use it to regulate levels of calcium and phosphorus, which are needed to keep them strong and healthy
If you are at all active over age 30 — by which I mean you EVER run, jump, or otherwise put pressure on your spine — you need to get lots of sunlight.
Most people have insufficient if not downright deficient levels of vitamin D. Spondylolysis and eventual spondylolisthesis is not a prognosis you want for your back.
Most western diets gets more than enough d-vitamin through food additives. Just a couple of slices of cheese per day and some milk is all the d-vit you need here apparently.
The old folk saying is to take d-vitamin supplements in all months that has an R in them. Probably sound advice
> Most western diets gets more than enough d-vitamin through food additives.
This is just wrong.
Per capita vitamin D defficiency and insufficiency in the US are estimated at about 30% and 40%, respectively [0] compared to about 50% insufficiency worldwide [1].
Lack of exposure to sunlight is a major predictor of vitamin D insufficiency, even in western countries [1]. Sunlight produces more bioavailable vitamin D than dietary sources, and the recommended daily vitamin D can easily be obtained from sunlight alone, while it is hard to obtain from diet alone.
> Just a couple of slices of cheese per day and some milk is all the d-vit you need here apparently.
Daily intake of cheese [2] and milk [3] fortified with vitamin D at the recommended daily value is insufficient to make up for a lack of sun exposure.
1. The "off by a factor of 10 due to a math error" is only applicable for one study. What do the other studies say about daily intake?
2. while there's plenty of evidence that vitamin D levels is associated with positive health outcomes, AFAIK evidence that vitamin D supplementation being associated with positive outcomes isn't very good.
edit:
3. I dug further and found there was a response to the study that you linked[1]. The response points out that the standard used by the original study (ie. supplementation levels that's needed for 97.5% of the population to achieve adequate serum levels of vitamin D) would cause people on the lower end to consume too much. Therefore the recommendation of 8000 IU (or any single number, really) is bad, and we should instead have different recommendations according to body weight:
>With this approach we estimated, for example, that doses of 1885, 2802 and 6235 IU per day are required for normal weight, overweight and obese individuals respectively to achieve natural 25(OH)D concentrations (defined as 58 to 171 nmol/L).
As such, even though there might be an error caused by "off by a factor of 10", everyone really shouldn't be upping their supplementation by a factor of 10.
I've been living in Australia and New Zealand, and have been terrified of sun exposure - during peak times (summer mid-day) it's scary how quickly you can burn.
However I also have low vitamin D.
My current strategy is to check the UV levels (I've got a widget on my personal dashboard) and whenever the UV levels are moderate or below, I try to get as much sun exposure as possible - shorts and t-shirt, or topless.
I then cover up when the UV levels are demonstrably high.
My theory is that low levels of exposure are very good - you get your vitamin D, whatever else you need, and your body starts to build an appropriate amount of melanin.
The worst thing to do is to avoid sun all the time, then suddenly get massive UV doses.
I've noticed that my hands very rarely get burned compared to other areas - my theory is due to constant exposure that part of my body is more resistant compared to the pasty areas.
My key point is that you can view the UV rating and protect yourself appropriately - e.g. high caution summer-midday, zero caution winter mid-day.
I'm in Australia and used to cycle here a lot. The back of my hands got a ton of exposure. They rarely burned, but now the skin on the back of my hands is visibly older than everywhere else. Looser, wrinklier, less elastic.
I'm glad I was forced to wear a helmet because otherwise my head would look weird ;)
>due to constant exposure that part of my body is more resistant compared to the pasty areas.
This is of course true, and it took me half a lifetime to realize I could get deep tans and stay out in the sun without any sunscreen, all it took was to "DCA" my way into sun exposure at the beginning of the summer. Concerted efforts to get 5, 10, 15, 20, 25, 30 minutes of unprotected sun exposure that slowly increase but not to the point of burning.
I also realized that sunscreen does not need to be so liberally or frequently applied- particularly mineral sunscreen, the thinnest possible film is all that is needed for hours of protection if you aren't swimming or sweating excessively.
It goes against mainstream advice that no sun exposure is good exposure, and that getting a tan is not healthy. However I never "tan" my hands and they don't look any darker, but I've never burned them, even though they're the place that will get the most sunscreen rubbed off. Ditto for feet.
I would like to think that I'm about as far a way from any sort of conspiracy theory as one could get. I have no time for anti-vax stuff, for example. A huge fan of "never blame on conspiracy what you can blame on stupidity". Etc. etc.
And yet ... when it comes to sunblock ... I try to avoid sliding into a conspiratorial stance, but let's just say that I don't use it [0], and I am very curious about the reason(s) why so many of us do.
ps. yes, I do know about skin cancer and have several friends and family that experienced it.
[0] if am going to be outdoors all day after a long period of being mostly indoors, I'll use it for a few days to protect my nose, lips, cheeks, ears and neck. Then I'll stop. I prefer sunblocking sleeves for my arms if that sort of is necessary.
I don't tan easily, and I don't think everyone is like me. I have friends who are even paler than me, and I get their use of clothing & sunblock. My curiosity is about why so many people use it, many of whom would appear to have no genetic requirement to do so.
Well, for a start, two people in that group wore sunblock religiously. But that's just anecdata, and I would certainly ridicule e.g. anti-covid vaccine arguments framed like that.
It seems that the argument that solar exposure causes cancer, and if not cancer than weathered leathery skin when you're older, has been widely and effectively made, and this has been enough to get most people to hedge and just use sunblock anyway.
I'm not convinced they're wrong - I'm more interested in the way sunblock brings out my own inner "conspiracy" self, even if I don't feel inclined to defend that version of me. It's actually a way to have some empathy towards people I otherwise feel no empathy whatosever for (e.g. the anti-vax crowd).
> It seems that the argument that solar exposure causes cancer, and if not cancer than weathered leathery skin when you're older, has been widely and effectively made, and this has been enough to get most people to hedge and just use sunblock anyway.
Yes, that is literally it. That is why people wear sunblock, including "religiously". They don't want cancer or prematurely aged skin.
> m not convinced they're wrong - I'm more interested in the way sunblock brings out my own inner "conspiracy" self, even if I don't feel inclined to defend that version of me
Again I'm completely lost. Is the conspiracy that people don't want cancer?
The "conspiracy" would be an multinational, multibillion-dollar industry making big money selling people a product they don't need and that could be harmful for their health.
N=1 but I've felt that I always sleep better when I've spent an hour in the sun that day. Considering how the sun has been a constant during much of human evolution, it just makes sense that our biological processes, both known and unknown, should revolve around it.
The obvious thing is that white people are white because they lost natural sunscreen living far from the equator. For that to have occurred the selection pressure must have been fairly strong.
Of course we do know that very heavy sun exposure and especially sunburn can cause cancer. It’s probably a case of moderation being good for you— not too little and not too much.
While I largely agree and I think it's pretty heavily sun related: there are plenty of other plausible mechanisms, I don't think it's quite that obvious or clear-cut.
E.g. it snows more as you go towards the poles. There are a lot of pale creatures in climates with snow, for the even more obvious natural selection pressure of "can hide better".
I think the big question is does it matter outside of vitamin d deficiency.
Severe vit d deficiency obviously is strongly negatively selective. So that by itself explains the evolution of white skin in northern climates. I dont think evolution can be used as evidence for other benefits, since vit d deficiency would cause that just by itself.
I was about to believe the results as they caution that it's only showing the benefits for northern countries like UK and they control for exercise, but then I saw in the paper that they characterize 'sun-seeking behaviour' variable through 'how many times a year would you use a solarium or sunlamp?'. I think people who use solariums is a very special category of people, and I am not sure one can extrapolate from that group to people who enjoy the Sun.
They asked about solarium use, outdoor sun in winter, and summer and various other questions. All showed lower hazard ratio. See table 2 in the 2014Lindquist study.
I agree. Despite the "more active" category being anyone who answered that they would use a solarium even once per year, they're still only 6% of the study population if I did the math right (see Table 1 on page 10). It also seems noteworthy that the study cited for that correlation was primarily investigating the factors driving use of tanning beds, not sun exposure.
This is no surprise to me since the UV here is actually sunlight related. Lots of co-conditions that affect it too. The paper said they adjusted their numbers for socioeconomic factors but still probably that adjustment won't be perfect.
Anyway, from all I have learned and done, the best health advice that I think applies to most people is moderation is the best. Trying too much and too hard on something will just backfire. Eating only meat and milk will cause cancer sure, but eating only vegetables and beans will also affect your health, namely nutritional deficiency. Etc. and etc.
I will just live normally while adjust things within limits and enjoy life while it is still good.
Is it just full spectrum light or specific UV sections?
I wonder if future building codes will require some type of intermittent full spectrum or UV light in certain areas. Maybe in a bathroom with a timer that shuts it off a few seconds after someone enters.
Normal glass blocks most of it. But pure SiO2 fused quartz does not. A bit more affordable is probably borosilicate glass and I would like to have my windows replaced with them, but it is not really sold as a common window. So you can probably get one, but it won't be cheap.
This is what I suspected. I couldn't believe for a second that our body didn't evolve to take advantage of sun.
So far I play it by ear: I wear sunscreen when I go out any time before 330pm. I don't get sunburn this way, but it's really hard to tell if I'm damaging myself. I also migrated from center Italy to Canada, so my skin is a bit more resistant (Sicilian heritage), but it makes it way harder to figure out the balance, since the sun is still strong in the summer.
I have a skin condition that flares up if I don't get sun. At first the doctor told me to avoid sun, but it got worse. Then by accident I got somewhat sunburned, and my skin improved.
While I am a big fan of the scientific method, it is difficult to do studies that don't have lots of confounding variables in this area, so when in doubt, use common sense is my rule. We evolved with the sun, so the most likely probability is we have at least some defense to it, and more than likely we evolved so that at least some exposure has benefit.