Sunlight and Vitamin D (2013) | Hacker News Reader

Sunlight and Vitamin D (2013)

ncbi.nlm.nih.gov

99 pointsluu133 comments

The author of this paper, Michael Holick, was a professor of mine and is highly controversial due to his industry conflicts of interest that he didn't disclose (https://www.nytimes.com/2018/08/18/business/vitamin-d-michae...) and his seemingly perverse testimony in child-abuse cases (https://www.propublica.org/article/michael-holick-ehlers-dan...). I regard his research with high suspicion.

    His fixation is so intense that it extends to the dinosaurs. What if the real problem with that asteroid 65 million years ago wasn’t a lack of food, but the weak bones that follow a lack of sunlight? “I sometimes wonder,” Dr. Holick has written, “did the dinosaurs die of rickets and osteomalacia?”

Isn't the whole article by a long shot - certainly an interesting counter point, thanks for the links and your thoughts.

I’ve heard hypotheses more stupid than that.

True, it's not bad as a thought, I threw it in there to tease others into the full article, it's the suspicion of zeal driven by funding that's the more damaging charge.

Still not as strong as the famous "Dinosaurs are thin at one end, much thicker in the middle, and thin again at the other end" conjecture.

What's controversial here? The benefits of Vitamin D is pretty well established

( it's a "vital mineral" after all.)

I read the summary and didn't see anything very adventurous.

Sure, it is vital, but he claims that lack of vitamin D underlies nearly all diseases of modernity, which isn’t well-established. Meanwhile he was making money selling vitamin D and not disclosing it, which makes his motivation seem suspect. It’s very easy for bias to obliterate the validity of research.

> Some among the medical staff and social workers involved in the case thought that Jenn reacted strangely to the discovery of her children’s injuries. She didn’t show emotion or seem bothered. Her affect was “flat,” according to the D.S.S. report. The hospital’s abuse specialist concluded that the baby girl’s fractures were “diagnostic of physical abuse” and that the bruises were “inflicted.” D.S.S. concluded the boy’s injuries were also the result of abuse. A factor in this determination was that Robbie and Jenn did not have “a plausible explanation” for the injuries. “We had no idea,” Robbie told me later.

What’s perverse is that the state can take your kids away without a trial and on the basis of evidence this flimsy, and the expectation is that you are guilty unless you can provide an explanation they’re happy with. To add insult to this obvious injury, you will be held to account for your affect when dealing with the state apparatus charged with taking your children away and subjected to weird psychologizing by people without any particular psychological expertise (as if there is a correct way to respond to these questions in the first place). A tired and overworked social worker who just came from collecting six kids from a drug den can operationalize a gut feeling that your responses were “flat” and you’ll go to bed that night not knowing where your children are or when (if ever) you’ll get them back.

The idea that this only ever happens to bad people who deserve it is naïve in the extreme, and the annals of CPS are full of cases of outrageous mishandling and overreach.

> But we’re talking about kids, so people turn off their brains and assent to ann extra-legal task force that can swoop in and break up a family on a hunch.

I think the reality is that making an error in either direction can lead to tragic consequences.

I don't know of any good solution to the problem.

Sorry, I deleted that part right after posting it, because I thought it was a little bit uncharitable. But I stand by the general sentiment, and I would just say that in our system of law and government, we have decided to solve this problem in one direction, which is to say that you are innocent until proven guilty. Taking an innocent person’s children away from them is an outrageous harm, and nobody should be subjected to it on the basis that extreme caution may save some other kids someday.

People should not feel guilty about saying plainly, no, you cannot take my children out of their home, just because an abundance of caution might help you prevent some real cases of abuse elsewhere.

Wow,

I find this funny because through the 50-70's letting kids sleep outside for a nap in the day time was normal in Scandinavian countries.

I remember the 1980's photo of kids getting a solar bath in some Hoth like area of Russia in the winter.

I like this study because it's starting to add "Sensible sun exposure" into the mix. I suspect that we're going to add "physical activity" to that next.

We didn't evolve for 100k years to work at desks for 8 hours a day and hide in houses. Persistance hunting was an outdoor day time activity. Foraging was an out door day time activity. Heading animals was an out door day time activity. Farming was an...

I found out the doctors are recommending vitamin D drops for infants. Yet they're loaded with all sorts of junk, like caramel color, polysorbate, etc. Sunlight produces vitamin D, helps break down bilirubin, and produces other beneficial substances. I know which one I'd choose.

Not all of them contain those additives [1] (I believe coconut oil is needed because cholecalciferol is not water soluble), but yes, I agree that they should not be pushed as a substitute for sunlight if you have the choice:

> Each concentrated drop delivers 400IU of vitamin D3, the form naturally found in the body, blended with premium quality fractionated coconut oil. The sugarless formula has no artificial colours, flavours, or preservatives, so it won't interfere with feeding.

[1] https://www.ostelin.com.au/products/infant-vitamin-d3-drops/

Nice! The ones at my pharmacies were filled with junk. This looks great.

Also from Scandinavian countries:

The babies who nap in sub-zero temperatures (https://www.bbc.com/news/magazine-21537988)

"In some studies they found pre-schoolers who spent many hours outside generally - not just for naps - took fewer days off than those who spent most of their time indoors," she says.

Yeah, this is a thing. My wife is Finnish and our first was born in Rovaniemi in early winter. Wasn't terribly cold but we had her on the parvike bundled in a stroller and she slept great.

I'm in Canada and have seen this first hand. snug as a bug in a rug even though it was -10C.

admittedly she was bundled up pretty good in the stroller, and it was near her usual naptime, but was totally asleep by the time we got home from the walk.

Then you have Australia here where there's no way sleeping outside during the day would be beneficial due to how harsh our UV rays are, unique to the rest of the world.

I agree, we didn't evolve for 100k years to work at desks for 8 hours and I think so much of that is a bigger problem in of itself, combined with lack of sunlight as just one piece

And the native Australians have the skin pigmentation to deal with it.

I definitely don't (not native, very pale)

I think the parent may be referring to the indigenous Australian (i.e. Aboriginal people) - who are basically black-skinned, and have been here for a lot longer than other races.

(Even they came to Australia from South East Asia originally - tens of thousands of years ago - back when there was a land-bridge).

I know, they were referring to them, I live in Australia.

I was just saying I’m not native and I have pale skin which is worse for sun damage, unlike our indigenous counterparts

Extreme equatorial sunlight still causes skin cancer even in full pigmentation islanders of northern Australia, PNG, Torres Strait, etc.

https://sundoctors.com.au/blog/how-aboriginal-peoples-master...

https://www.ourmobandcancer.gov.au/ways-to-help-protect-agai...

There's some additional protection, even so most people with long Australasian family histories hang out under trees at midday.

  Mad dogs and Englishmen
  go out in the midday sun

EDIT: come to think of it, this may explain the popularity of pith helmets in the chap hop scene: https://www.youtube.com/watch?v=eELH0ivexKA

Hard to believe but I remember australian grandparents claiming you would be a "good mum" if you left infants in the sun. But I also remember being told dark tans were healthy, and people without then looked sick.

In the case of infants, sometimes their ability to break down bilirubin is reduced. small amounts of sun exposure could be recommended

My understanding is when children are born they may get put under a uv light for this. Your grandparents knowledge may be prior to modern treatment

Australia's UV rays are not unique to the rest of the world. There are lots of places in the world where the UV rays are much stronger than in Australia.

"So where on Earth’s surface would we expect the highest UV? Peak UV should occur within the tropics (high sun, low ozone), at a high altitude site, in the Southern Hemisphere. Near the Tropic of Capricorn, overhead Sun occurs during the period when the Earth- Sun separation is a minimum"

Satellite data clearly shows that UV is approximately 1.5x stronger in Peru than Australia, for instance.

> Satellite data clearly shows that UV is approximately 1.5x stronger in Peru than Australia, for instance.

Does this account for the diminished ozone-based UV filtering Australia is subject to?

Yes. Other places, like Peru, also have diminished ozone.

I should have said unlike many places around the world.

My point being in relation to the parent comment was that here you can’t just sleep outside all day. And being outside for extended hours here does irreversible damage without sunscreen very quickly

the first studies that determined the connection between sunlight and skin cancer were based on Australia cabbies.

US cabbies got skin cancer on the left side, because their left arms or sides hung out the window / got more sun. Meanwhile the Aussie cabbies got it on their right side, and at high rates (because anglo-irish in a desert).

+1.

Also a few animals sweat like us. We are indeed not built to sit in one place.

Sweating:depression::sunlight:infection.

In college, my Earth science professor claimed that there was no acceptable amount of sun expose since it can give you skin cancer.

I understand the two are correlated, but it made no sense to me. Only in the last few hundred years have humans been able to be indoors nearly 24/7.

Maybe the percentage of skin cancer deaths was acceptable back then? We now try to save every individual no matter what disadvantage they may have been born with thanks to modern medicine and surgery, and that practice has been changing our gene pool.

The genes that predispose you to melanoma are probably the same genes that makes your skin white...

A theory just popped into my head.

For hundreds of thousands of years, we had no soap. We did have water, but swimming and washing in a summer stream isn't hot water, and it's hot water which strips away the oils. And even pre-20th century, people did NOT bath in hot water daily.

Often it was just armpits + groin in a sponge bath.

What if our skin was protected by our own oils? I can imagine that even a small amount of oil, would reduce the amount of UV that gets to the skin.

I know sunblock has minerals(zinc, etc) in it to reflect the sun, but I just googled there are oil based sunscreens too:

"Chemical absorbers: Chemical (or organic, meaning carbon containing) sunscreen ingredients form a thin protective film that absorbs UV radiation before it penetrates the skin."

I can easily imagine that our own oils could provide protection, and block UV but let good frequencies of light through. Yet now we wash a lot of that oil off, with hot showers daily, and shampoo and soap which runs down our body as we shower.

Would be an interesting study.

edit: another thought! The oil on our skin is often policed by bacteria. The bacteria eats that oil, and also any organics (skin flakes, or stuff that sticks to the skin).

That's another level of shield. I imagine that without hot showers, and loads of soap, that layer of oil has bacteria multiple layers deep. And that bacteria moves. A moving, sunshield.. in addition to the oil.

And of course, bacteria exudes waste. That waste is going to have carbon in it, too. So our skin oil would be combination of the oil + living shields + their waste.

I imagine the waste would build up after a while too.

edit2: A harsh response from KennyBlanken, who seems to disagree.

However, this poster quite literally ignores things I stipulated, or gets things mixed up. He then ends with harsh criticism, which seems very un-HN like (eg, personal attacks).

That said:

* Skin oil contains a myriad of ingredients, fatty acids, salt, complex acids, bacteria, their leavings, and more.

All of this is simply ignored by Blanken, who just says "skin oil doesn't block UV, because it doesn't have the same precise ingredients as over-the-shelf sunblock". Further statements about "Google this" are provided, yet clearly I did a bit of quick research, as I provided a quote about sunblock. Again, very un-HN like.

* Weird statements about how long soap has been around for, when all I indicated is that for "hundreds of thousands of years" we had no soap, which is entirely true, and obviously stated in terms of how we evolved. This fact seems to have been missed in the reply, however.

* Discussions about how soap has been around for a while, meanwhile missing the entire point that most humans pre-20th (as I stated) typically just did the sponge bath thing. People didn't shower, and most of humanity did not have running water until the 20th, regardless of rare rich Romans.

None of these rebuttals seem to even consider that the scientific process starts with random thought, eg as I said "A theory just popped into my head.", then consideration, then debunking via actual, real research.

As opposed to some 19th century British-Science-Guild like huffing, including personal attacks and so forth.

KennyBlanken, perhaps you could debate more politely? And follow the guidelines a bit more closely?

https://news.ycombinator.com/newsguidelines.html

Imagine all these small qualities of life that are destroying us without us knowing.

Skin oil does not provide any UV blocking.

The oil in sunscreen is to make it spreadable and dilute the UV-absorbing ingredients, which are things like avobenzone, oxybenzone, and so on.

No offense, but you could have googled "active ingredients in sunscreen."

Further: just because something is called an "oil" doesn't mean it has any similar physical properties compared to another oil.

Recipes for soap date back something like 5,000 years, by the way - and probably were passed down by oral history or demonstration even earlier.

You don't seem qualified to be making (or evaluating) the theories you are coming up with. Not in terms of basic scientific knowledge, critical thinking skills, or research skills.

Your "people didn't wash back then so they had natural sunscreen" is about as well-reasoned as the people who think keto is the best diet because "it's what cavemen ate" (hint: people ate whatever was available to them in their area.)

I mean, anecdotal, but... unhoused people, soldiers, campers, etc sure seem to get plenty tan when outdoors even when not taking regular hot showers.

Anyway, it's good to think outside the box, even if this theory is probably a miss.

True, but white people historically lived in colder climates with (naturally) less sun exposure , which has changed in the last couple centuries.

You have it reversed. The color of your skin determines how much UV protection you get. Skin color is 1-1 correlation to the average hours of daylight a population experiences. High melanin skin is required to live in the equatorial regions to prevent over exposure to UV rays. Low melanin skin is required in the northern regions to prevent under exposure to UV rays.

We saw a mass migration of eastern Europeans to the middle east mid 20th century and the result was the catastrophic increase in skin cancer rates.

We saw a mass migration of middle Easterners to great lakes region in the same period and we saw a catastrophic increase in depression rates.

There are several kinds of skin cancer: carcinomas (which don't usually kill you) and melanona (which does). Carcinomas are indeed positively correlated to sun exposure, but oddly enough melanoma is negatively correlated: sun exposure protects you from melanoma.

Do you have sources I can read on this? I wife has had a couple bouts of melanoma in her mid 20s and her dermatologist tells her to stay of of the sun.

Her dermatologist is right. Take medical advice from MDs, not HN.

My wife is also a melanoma survivor (Stage III) and yeah, the notion that sunlight is negatively correlated with melanoma is utter nonsense.

> but oddly enough melanoma is negatively correlated: sun exposure protects you from melanoma.

I hate to be that guy, but: citation needed.

I did a quick search and the best I could find was speculation that sun might be protective, but the majority of what I found said sun exposure increased your risk of melanoma.

(citation needed) on the melanoma. UV is basically identified as the main cause of melanoma. Unless you meant exposure in low-UV situations. But that's a massive caveat that really needs to be added to that message.

Everything about https://en.wikipedia.org/wiki/Melanoma basically disagrees.

That does not sound correct. Sun exposure is still linked to melanoma risks. Regular sun exposure does increase protection (due to melanin in skin?) but doesn't remove the risks.

Being active in the sun for long period in New Zealand or Australia for example would put you at higher risk for melanoma due to higher UV exposure

Exposure to UV increases your risk of getting cancer, statistically.

Not getting sufficient sunlight - not just for vitamin D production but other things - increases the risk of other health impacts, statistically.

For decades people freaked out about the former, without considering the latter.

I think the research supports what you're saying.

My professor though was essentially saying "stay out of the sun". It was a bit of a charged lecture since his daughter developed skin cancer.

But, my take is sun exposure is perfectly worth the risk. A life without being outside/being in the sun doesn't sound very enjoyable, though of course moderation is important.

There's a big difference between sunbathing in Scandanavia and sunbathing in Florida, though.

I agree.

But you left out one small piece of information:

If you didn't go outside for food you died. If you didn't go outside to till your field you died. If you didn't travel with your animal herd you died.

The CDC does not recommend seeking sunlight to promote the production of endogenous vitamin D[1]:

> The skin can produce only a limited amount of vitamin D at one time. Once the body has reached this limit, spending more time in the sun will not continue to increase vitamin D levels. However, continued time in the sun will increase your skin cancer risk. There is no known level of UV exposure that would increase vitamin D levels without also increasing skin cancer risk. Vitamin D can be obtained safely through food and dietary supplements without the risks associated with overexposure to UV.

Same thing with the EPA[2]:

> Get Vitamin D safely through a diet that includes vitamin supplements and foods fortified with Vitamin D. Don't seek the sun.

[1] https://www.cdc.gov/cancer/skin/basic_info/outdoors.htm

[2] https://www.epa.gov/sunsafety/sun-safety-tips

Reads like CYA warnings, not lifestyle advice

"Please do not leave the mines. Everything you need is available within the mines; you must only do your mining. It is dangerous outside the mines. If you insist on leaving the mines, you will need our protections or you will die. You will need to do more more mining to be protected. Please do not leave the mines. You do not want to leave the mines. It is dangerous outside the mines"

Here's what the article says before the quote I posted above:

> Spending time outdoors can improve overall health and wellness. The outdoors offers many opportunities to be physically active. Time outdoors may also promote mental health and stress reduction. While enjoying the benefits of being outdoors, people can decrease skin cancer risk from too much UV exposure by using sun protection. Protect yourself by staying in the shade, wearing protective clothing, and applying and re-applying a broad spectrum sunscreen with a sun protection factor (SPF) of 15 or higher. Communities can help by ensuring shade is available in public parks. Schools and businesses may consider adding shade to school grounds and places were people gather outside.

I still can't tell if you're posting these quotes to highlight how Kafkaesque and self-satirizing things have become in modern institutions or if you earnestly think they refutes something in the submitted paper.

The quotes don't seem to speak for themselves, so sharing your own interpretation might help the discussion more than just posting further selections.

It's literally an article promoting the health benefits of being outdoors. It happens to provide a caveat about sun exposure at the end given that it's from the CDC website's section about skin cancer. I'd hardly call that Kafkaesque.

The CDC has to provide advice to people as far north as Alaska, as tropical as Hawaii, and as far south as Miami - for a very heterogeneous population that doesn't understand nuance and tradeoffs.

Hawaii is the southern-most state in the USA.

I know, but then the sentence would be clunky. It's usually not considered "the south".

And the elite are shocked, shocked! To learn we don't trust their shamans.

Wow, that is surprising.

Even Australia, a country with high skin cancer rates and high public health campaigns to reduce it recommends people get Vitamin D from the sun (although in limited amounts in summer):

https://healthybonesaustralia.org.au/your-bone-health/vitami...

The wind is shifting on this one. For example: https://www.health.gov.au/ministers/the-hon-mark-butler-mp/m...

I caught some free-to-air TV recently and they're running ads that make the sun sound as dangerous as cigarettes. Scenes of folks all like "I thought I'd just have a bit of a garden. Then I got skin cancer." It's a big push to change attitudes for a historically sun-loving country.

There is no known level of car commuting that would increase salary potential without also increasing car accident risk. Salaried income can be obtained safely through remote work without the risks associated with car commuting

I mean you joke but in my book, participating in the most dangerous thing any of us do two times less per day is a win in my book. Plus all the other nice things like, destroys the environment a bit less, less traffic, and so on.

I don't know why you are getting down voted. Driving is also the most dangerous thing I do each day and there are countless good reasons to ditch the daily commute. For both me and society at large.

Yeah but there's a Pareto frontier where if you can't find a remote job, driving is probably better than being broke

this assumes that there are not highly lucrative roles that aren't in person.

most of the director and above roles require pretty consistent in-office presence, for example.

"There is no known level of UV exposure that would increase vitamin D levels without also increasing skin cancer risk."

This seems off to me. Sounds like they're saying there's no known safe level of sun exposure. I wasn't able to find any studied, including on thier page, supporting that. Most of the studies I saw actually use infrequent UV exposure populations for the baseline. Are there any studies that show 5 minutes of exposure a day is significantly worse than 0 minutes?

Why disagree?

What they neglect to mention is that increased sun exposure reduces all cause mortality, including from melanoma. Yes, it does increase skin cancer, but paradoxically reduces mortality from skin cancer.

"Additionally, assessment of sun exposure parameters has consistently shown an association between the development of malignant melanoma and short-term intense UV exposure, particularly burns acquired in childhood. As a consequence, protection of the skin from UV radiation is an integral part of skin cancer prevention campaigns. However, more chronic less-intense UV exposure has not been found to be a risk factor for melanoma and in fact has been found in some studies to be protective."

https://link.springer.com/chapter/10.1007/978-3-030-46227-7_...

Even after how much they botched the Covid response, you still go to the cdc for basic vitamin advice?

“Natural? That must be bad for you. Take these supplements that are manufactured by companies we totally don’t own stock in”

Is the implication that the body needs more Vitamin D than the body will produce through sunlight exposure? I thought sunlight exposure was best because it wouldn't lead to _too much_ Vitamin D.

The OP article basically concludes the same thing for those of us above and below 33° latitude.

Australia recently updated its sun exposure guidelines to allow for the fact the some sun exposure is required to generate vitamin D. It's a balance, with influences from genetics, including skin colour.

The advice is tailored for Australian conditions. Australia is the melanoma capital of the world[1], so it puts a fair bit of effort into trying to get this advice correct.

https://www.theguardian.com/australia-news/2024/feb/13/austr...

https://www.assc.org.au/wp-content/uploads/2023/01/Sun-Expos...

[1] https://www.cancer.org.au/about-us/policy-and-advocacy/posit...

Well, that review is quite old and out of date now. We now know that vitamin D doesn't in fact protect against these diseases (from the results of large vitamin D supplementation trials). However, a number of large studies show that sunlight itself does give significant protection against cancer and cardiovascular disease, and reduces all cause mortality. It is thought that this effect is due to skin-derived nitric oxide rather than vitamin D.

https://onlinelibrary.wiley.com/doi/full/10.1111/joim.12251

We still don't know much about vitamin D supplementation one way or the other. Most of those large studies were badly flawed in that they gave rather arbitrary fixed doses to subjects rather than titrating doses to hit target blood levels.

There have been a large number of trials now, and I see no mention of the flaws you outline in this review:

https://www.bmj.com/content/366/bmj.l4673.short

Not saying you're wrong, just curious if you can point out which trials were/weren't flawed in this way, and a reference to a review which mentions it.

I spot checked a few of the studies in that meta analysis and they all suffered from the exact same methodological flaw that I pointed out above. They administered fixed doses to subjects rather than titrating the doses up or down to hit target blood levels.

Yes, this is mentioned in the limitations of that review:

"The dose of vitamin D used in included trials varied. Our study could not accurately compare equivalent daily vitamin D supplementation dose in the included trials because they all had different treatment regimens and dosing intervals (daily, weekly, monthly, or bolus doses). This might be one of the reasons why this study did not determine an effective daily dose of vitamin D supplementation. Furthermore, the vitamin D status before, during, and after treatment is useful to determine the effectiveness of vitamin D supplementation in improving the actual vitamin D status. Long term vitamin D status is expected to be a much more accurate, reliable, and important clinical parameter compared with a daily dose of vitamin D supplementation. However, previous trials were limited in providing such data. These limitations and uncertainties associated with vitamin D supplementation dose and vitamin D status in treatment and control groups warrant further investigation."

This paper is from 2013. It is out-of-date. More recent large scale studies of Vitamin D supplementation show no benefit, except in cases of substantial deficiency.

https://www.nature.com/articles/s41574-021-00593-z

Sunlight, however, does show benefits. This suggests that Vitamin D is just a side effect of sunlight exposure, and does not by itself do any good.

Interesting about "supplementation of vitamin D-replete individuals does not provide demonstrable health benefits". The OP article does clearly call out that the benefits of vitamin D are in cases of _vitamin D deficiency_. It goes on to state that there is a "worldwide vitamin D deficiency pandemic" and mentions that 32% of children and adults have a circulating concentration of 25(OH)D < 20 ng/mL (i.e. vitamin D deficient).

So I think the broader point of the article was that many of us are vitamin D deficient, and those of us that are, have increased health risk, and that's why we need to supplement our vitamin D.

Yet nearly every controlled trial supplementing Vitamin D has limited or no effect, except maybe in the most deficient people. Many many trials have been conducted. Vitamin D advocates always have an excuse — it’s too little vitamin D; no, actually you also have to add Vitamin K2; etc

Part of the problem of all the observational trials looking at vitamin d is that low vitamin d is a biomarker for being less healthy. People who are ill spend less time outdoors. People who spend more time outdoors are already healthier and are also getting other benefits from their outdoor activities.

You can try to control for all of these things, but every time we actually try to test what happens if you give people Vitamin D, we find almost no benefit.

Well, I can tell you that I'm on a vitamin D supplement and there's very definitely a direct benefit to it treating early osteomalacia.

Yes, rickets and osteomalacia (when caused by vitamin d deficiency) are both treatable with vitamin d. Randomized controlled trials clearly show this, unlike the vitamin d trials for most other things that people are pushing vitamin d for.

Everyone should probably have their blood level of vitamin d tested. Most people are not going to see dramatic changes to health from vitamin d supplementation.

I have had psoriasis for over 30 years now. The only consistent thing that makes it go into regression is getting a lot of sun in the late spring / summer. Unfortunately I live in a northern state, so over half of the year I do not get UVB from the sun and my psoriasis starts coming back in the mid-late fall. I have tried Vitamin D supplements but they don't seem to work for me. Even at high dosages.

Fascinating! Both my wife and my mother have psoriasis and they both say the exact same thing! They both swear by sunlight as a way to treat it. My wife has actually gotten Dermatologist-applied blue light therapy which has done wonders for her scalp.

I will have to look into blue light therapy. I used to have psoriasis really bad on my scalp. This might sound gross to some people but what cured it for me was to not use shampoo & conditioner every day in the shower. I still wash well with warm water but ever since I stopped using "products" in my hair every day, I have not had an issue with scalp psoriasis in over 15 years. I will take naturally oily hair over scalp psoriasis any day.

I wholeheartedly agree. Most people aren’t willing to go through the oily phase, but if you go long enough your scalp will regulate its oil production and then you don’t have oily hair OR dry scalp. Source: haven’t used shampoo in over 8 years; have beautiful hair. ha

I remember some chatter on HN that sun exposure also causes the skin to produce nitric oxide, and that this is potentially under-studied.

Do you think you'll ever move to a state with more sunlight?

I have thought of moving to Nevada or Arizona just to be closer to the equator. However, it is going to be hard to leave the PNW because I love hiking and backpacking. Maybe I should snowbird down south in the winters once I ditch work for good.

Consider a one-week trip to Hawaii in the darkest time of winter; supplementation studies have shown that the body can safely absorb and store 100K IU, that it takes about 2 months to deplete such an amount. Your skin produces 20k IU in 30 minutes on a sunny day at the beach (wearing a swimsuit). If you're in the PNW (or central Europe at the Southern German border) your skin cannot produce vitD from October through April because of how low the sun is in the sky even at its zenith.

I definitely should do more sunny trips in the fall/winter. I am going to try tanning in a UVB bed a couple times a week during the bad months this year. I have heard that it has helped some people.

> However, it is going to be hard to leave the PNW because I love hiking and backpacking.

I'd argue that the desert southwest is a great place for hiking though you obviously have to plan around the extreme temperatures. But the mountain ranges tend to be significantly cooler and a viable option in the summer. The big downside, more for backpacking, is that you either have to: carry all your water, stash water ahead of time, or refill at springs that may be unreliable.

Yeah, I have only hiked day trips in Nevada and Arizona in the Summer. I definitely want to try at least an overnight trip in the cooler months or at the higher altitudes. It is on my list of things to do.

Is it possible you need other vitamins to utilize the higher levels of D, such as vitamin K? Or perhaps it's not vitamin D related but some other benefit of the sun?

Perhaps, I have heard about taking vitamin K with D and have tried supplements with both. You are right, maybe there is something else besides vitamin D. Maybe something to do with melanin production.

My brother has psoriasis and lives in a northern state as well. He spent some time in Australia a while back (late 90s) on a research assignment and said his psoriasis was never better.

can you clarify 'was never better' please

More sunlight, especially UV = fewer symptoms

aha, so going to australia made him better? thanks!

FWIW my sister had regular sunlight therapy for hers as a teenager, it sounded essentially like a tanning bed at the dermatologists office but probably had particular settings or something. She also used a product called Coal-tar shampoo and skin lotion, not sure if she still does (hers has reduced a lot as an adult). I don’t recall vitamin D directly ever being part of her treatment.

Yeah, I use coal tar as well. I would recommend it over anything else I have tried. It is kind of messy and annoying to apply but worth it if for nothing else than to relieve the pain of dry cracked skin.

While not dirt cheap, UVB lamps/LEDs for treating skin diseases like psoriasis are fairly common and seems like a well proven treatment?

- https://sci-hub.se/10.1016/j.det.2019.08.001

- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8634827/

- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5597604/

I’m not sure I understand why living in a northern state prevents you from getting sun exposure for part of the year. Is it cold out? Sure. But if the benefits are as much as they seem to be for you, I’d endure some cold exposure in order to get that sun therapy.

It has to do with UVB rays, rather than UVA rays. UVB rays only show up where I live from mid April to around October. Other months of the year, the Sun is too low in the sky and those rays bounce off of the atmosphere. The closer you are to the equator, the more yearly coverage you get of UVB rays.

Interesting

The sun can’t be at too much of an angle or the UVB can’t get through the atmosphere.

Anecdotal, but I had psoriasis and I accidentally got rid of it. I moved into a new flat and, due to the state of the kitchen, ate junk food for a few days, then went the other way to eat anything but junk food. After a week my skin got better in many ways and I realised that I had quit sugar. So I decided to make a streak of it, for thirty days. Thirty days came and went, with added sugar removed from my diet. So I still eat fruit, which is fine to enjoy, but absolutely no added sugar enters my home under any circumstances. Sweeteners are banned too, even honey, because that is probably sugar pretending to be honey.

As well as the psoriasis there were other skin blemishes that I had always had, yet they had gone.

No added sugar means I always have to home cook, from single ingredient foods. There were a dozen other health gains and just moving is so much nicer these days. I haven't any time for scales, tape measures and so forth, but my belt does not lie.

I would highly recommend that you do a trial of not eating added sugar if you have the misery of psoriasis and have been given creams that don't work and have assumed it is vitamin D for that to work for a bit. I am no doctor and my experience is anecdotal, but this has to be the best thing ever for my skin.

Regarding the article, my skin feels naturally moisturised and I have no body odour to speak of. It turns out that sugar is really bad for the skin and I am wondering if it is this sugar in everything we eat that is the problem rather than the sun when it comes to protection from the sun.

My view is that suncream only makes sense if you eat a lot of sugar, and that restored skin, with no added sugar, is much more resilient. This summer I am going to put the suncream away and see if I die of skin cancer. Well, that is an exaggeration, but my view from ditching the added sugar is that the sun is not the enemy but sugar might be.

I do Keto. I think it does help but isn't a cure for me by itself. That plus a little bit of exercise does help me keep the weight off though.

I would definitely use sunscreen if you are in the Sun for over an hour or two depending on your skin type though. Sunburn = bad.

If you decide to supplement vitD in winter time note that US government recommendations are way too low [1][2] compared to normal practices in Nordic countries: should be daily 3000 IU for kids (toddlers and up) and 8000 IU for adults.

[1] It's not sufficient for kids to take the bare minimum that avoids rickets. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3476526/)

[2] Statistical error in estimation of the recommended dietary allowance (RDA) for vitamin D (https://www.jpmph.org/journal/view.php?number=1915)

This is anecdotal, but I can confirm this from my experience. I was taking 2000 IU per day, and I felt the effects of seasonal depression. When I increased it to 5000, I felt so much better.

I agree that the recommended dose is probably too low, but part of the reason for the discrepancy may be poor absorption of many supplements. I ended up with side effects (racing heart and thirst that wouldn't go away - which reliably went away when I backed down the dose and came back when I upped it again) from only 2000IU/day (as an adult). But I was taking it in the form of drops under the tongue (and as a combined formulation of D3 and K2) which I suspect is absorbed much better than the typical pills which are swallowed.

> It has been estimated that as much as 25% of health care dollars could be saved just by improving the world’s vitamin D status.

Seems like a low hanging fruit for the government.

Smells like BS.

The source is a 1989 paper about a 1983 study about 37 people wth colon cancer..

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

The issue you have is the study was from 1983 and you were expecting it to be repeated yesterday so the study must be bs? What a weird generation who won't watch an old movie until it's redone poorly.

So you're saying lack of sun increases health care expenditure? Excellent.

https://www.youtube.com/watch?v=IyjJbhuwGkU

It certainly was, although capping sun exposure to pre cancer levels was the message:

    One of the most successful health campaigns in Australia's history was launched in 1981, when a cheerful seagull in board shorts, t-shirt and hat danced his way across our TV screens singing the jingle. 

    'Slip, Slop, Slap!
    It sounds like a breeze when you say it like that
    Slip, Slop, Slap!
    In the sun we always say 'Slip, Slop, Slap!'

https://www.youtube.com/watch?v=b7nocIenCYg

and then there was the Life, Be in It campaign (1975) promoting exercise and good diet, eg:

https://www.youtube.com/watch?v=GNjEge3Awl8 https://www.youtube.com/watch?v=uuqDlF8DUuY

That does seem very unreasonable or misleading. If they are implying that everyone should just supplement, it would be bullshit, since current science as far as i know is that supplementation hardly does anything. Impeoving vitamin d status through solving the underlying conditions that cause it, this may be an argument, but then it's phrased completely the wrong way.

Is sunlight really very bad for you? There seems to be extra obsession to protect against sun in the US. Everyone is plastering their kid with sunscreen. I just do not know how much of it is true. If it was really bad for you places like Italy and Spain would be heavily impacted by it.

When my kids were young we used sunscreen in moderation to prevent burns. Once they had a tan we didn't worry about it unless we were going to be sitting in the sun for hours.

A lot of people with ancestors from the Mediterranean have darker skin, which could have a big impact. Ozone levels also differ around the planet.

Gotta be concerned with the garbage in sunscreen too

There have always been clear benefits to sun exposure. While I can't speak about what the public opinion is these days, there's plenty of recent research covering that seem to have balanced risk/benefit analysis.

Alfredsson, Lars, Bruce K. Armstrong, D. Allan Butterfield, Rajiv Chowdhury, Frank R. de Gruijl, Martin Feelisch, Cedric F. Garland, et al. “Insufficient Sun Exposure Has Become a Real Public Health Problem.” International Journal of Environmental Research and Public Health 17, no. 14 (July 2020): 5014. https://doi.org/10.3390/ijerph17145014.

Hoel, David G., Marianne Berwick, Frank R. de Gruijl, and Michael F. Holick. “The Risks and Benefits of Sun Exposure 2016.” Dermato-Endocrinology 8, no. 1 (October 19, 2016). https://doi.org/10.1080/19381980.2016.1248325.

Lindqvist, P. G., E. Epstein, K. Nielsen, M. Landin-Olsson, C. Ingvar, and H. Olsson. “Avoidance of Sun Exposure as a Risk Factor for Major Causes of Death: A Competing Risk Analysis of the Melanoma in Southern Sweden Cohort.” Journal of Internal Medicine 280, no. 4 (October 2016): 375–87. https://doi.org/10.1111/joim.12496.

That is really what I am trying to say. I bet all in all just going out in the sun without sunscreen is better all benefits/risks of both sides considered.

it depends when and where. Some latitudes or times of day may have relatively safer angles of sunlight.

Mushrooms when exposed to ultraviolet light can then have considerable amounts of dietary Vitamin D

https://en.wikipedia.org/wiki/Edible_mushroom#Vitamin_D

Otherwise there really isn't much in the diet that naturally or regularly contains it other than milk that has been supplemented.

One thing I've found helpful is that you can find out the current UV levels for your location, e.g. https://www.arpansa.gov.au/our-services/monitoring/ultraviol...

I live in the antipodes (near the ozone hole), am fair skinned, burn easily, and have had low vitamin d levels when I've had them checked.

I cover up or am very careful with sunscreen when the UV is high, then try to do the opposite (no sunscreen, lots of exposure) when UV is at lower levels. The idea is to generate vitamin d at safer times while avoiding skin cancer.

I also supplement with vitamin d pills.

The gist: > As a result 1,25-dihydroxyvitamin D influences a large number of biologic pathways which may help explain association studies relating vitamin D deficiency and living at higher latitudes with increased risk for many chronic diseases including autoimmune diseases, some cancers, cardiovascular disease, infectious disease, schizophrenia and type 2 diabetes >A three-part strategy of increasing food fortification programs with vitamin D, sensible sun exposure recommendations and encouraging ingestion of a vitamin D supplement when needed should be implemented to prevent global vitamin D deficiency and its negative health consequences.

nit: Add an extra line between your lines for better formatting. HN eats single line-breaks.

I'm fair skinned and the ozone layer is very thin where I live, so I have to cover up a lot when I go outside.

Which reminds me, I should take some vitamin D.

(2013)

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