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Nice to see more benefits of Vitamin D. Highly recommend the supplement for tech workers who spend a lot of time indoors. I take 125mcg/5000IU a day when I wake up and it's subtle, but I just feel a little better with it. Sports Research is a good brand (not affiliated).

Nothing better than getting some real sun though, especially in the morning.

A lot of people in the first world are heavily deficient in vitamin D, and deficiency is linked to a whole host of health issues and vulnerabilities. It's dirt cheap and essentially completely safe below toxicity levels (which are quite difficult to hit - I take 10,000 IU daily, and even with that my bloodwork shows me in the lower quartile of the normal range).

Its metabolite is a steroidal hormone, so it's pretty obvious why it would be beneficial for anti-inflammatory purposes, but it also modulates some key cardiovascular gene expression, too.

That seems like far too much, especially if you ever go outside. In the UK doctors recommend no more than 1,000 IU/day during the winter months. Any more than that is only if you are actually deficient. It seems really hard to get clear answers on it, though. People taking 10x the recommended dose of something seems strange. It makes me think it's being stored somewhere that isn't your blood. It's fat-soluble after all. Why on earth would you take so much anyway?
He is actually deficient, and 10k IU is not that unusual.
When I was deficient I took 20k IU per week for 6 weeks and was back to normal levels at the end. Taking 10k IU a day indefinitely seems insane. The numbers are just so wildly different.
Good thing he's measuring his levels and keeping an eye on them.
I get bloodwork done twice annually, so I have a very accurate idea of what my levels are. The dosage is the recommendation from my doctor based on my bloodwork. The goal isn't just staving off seasonal affective disorder, but actually trying to get me roughly into the middle of the ideal range because of its myriad health benefits.
> In the UK doctors recommend no more than 1,000 IU/day during the winter months.

You're mixing two pieces of advice:

1) everyone 'should consider' taking 400IU daily over winter (under-4s year-round);

2) infants should not take more than 1,000IU daily (adults: 4,000IU)

https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-...

Of course, 4,000 daily is still only 28,000 weekly, not 50k, but GP is doing it on the basis of blood work & physician review; the NHS website certainly isn't intended to contradict that, it's generic advice in lieu of it.

Vitamin D is a fat soluble vitamin, so of course it is being stored in fatty tissues in the body. Where else would it be stored? Your blood stream is not a storage mechanism but a transportation mechanism.

Daily Recommend Values for basic nutrients aren't the same as medicinal dosages. Nobody ever gets Daily Recommended Values for all the essential nutrients anyways, and many of them are regularly exceeded by a single multivitamin or dish. They're also somewhat arbitrarily defined. Like the food pyramid, you should take them with a grain of salt.

So what if the vitamin D is being accumulated in fat and the blood can only carry so much regardless of how much is accumulated in fat? Seems dangerous to keep taking more and more at a really high dose doesn't it?
Toxicity is defined by serum levels, and is at around 100 ng/mL. My last labs put me at 39 ng/mL, and I've been taking vitamin D for years. Under 30 is considered insufficient, under 20 is deficient.

I mean, yeah, sure, don't chug bottles of the stuff without measuring for years on end, but you have to take a lot to hit toxicity levels. And periodic bloodwork to keep an eye on numerous metrics is a generally good idea anyhow.

> People taking 10x the recommended dose of something seems strange

Not really. If your blood work shows shows you're low, you'll get a prescription for a very high dose. 100x is normal for some vitamins

I second the Sports Research brand it's my favorite based on their obvious careful choice of fillers.

Anyway, yes the full spectrum of the sun provides much more, not only UV for vitamin D but the red/infrared part of the spectrum which is great for cellular energy.

Also, ask your doctor to get yours tested! A couple years ago, my D was on the low end (31.7ng/mL; 30-100 is normal). I've been taking 5000IU of D3 since then, and a lab last month had me at 59.1. That seems to be about the perfect dose for me, and it's dirt cheap.
I just take D3 50K a week, what a doctor once recommended when I was tested and found almost with something like 6 ng/dL of D in my system.

BTW, did they tell you to back off or cut your dose? at 59 ng/mL you're in the danger zone.

They said keep going. 59 is where NIH says you want it to be. From https://ods.od.nih.gov/factsheets/VitaminD-Consumer/ :

* Levels of 50 nmol/L (20 ng/mL) or above are adequate for most people for bone and overall health.

* Levels below 30 nmol/L (12 ng/mL) are too low and might weaken your bones and affect your health.

* Levels above 125 nmol/L (50 ng/mL) are too high and might cause health problems.

Although there is a weird confusion of units. The results I'm looking at right now use ng/mL, but lists the numbers for nmol/L. The report includes a graph like:

30 ng/mL --- 59.1 ng/mL (in range) --- 100 ng/mL

People who avoid the sun more likely to take vitamin D supplements?
This is the most plausible reason.
The most plausible reason is that the scientific peer-reviewed result is correct, not the tiring "correlation does not imply causatian" commenter on HN who at most skimmed the paper.

2009: > Epidemiological data show an inverse relationship between vitamin D levels and breast cancer incidence. In addition, there is a well-documented association between vitamin D intake and the risk of breast cancer. Low vitamin D intake has also been indicated in colorectal carcinogenesis. A vitamin D deficiency has also been documented in patients with prostate cancer, ovarian cancer, as well as multiple myeloma. Larger randomized clinical trials should be undertaken in humans to establish the role of vitamin D supplementation in the prevention of these cancers.

it’s a small difference in a small group. And relying on self reporting for sun exposure.
> The most plausible reason is that the scientific peer-reviewed result is correct, not the tiring "correlation does not imply causatian" commenter on HN who at most skimmed the paper.

Quite the odd take given the last sentence in the abstract of this paper is essentially "correlation is not causation":

> In conclusion, regular use of vitamin D associates with fewer melanoma cases, when compared to non-use, but the causality between them is obscure.

They could be just saying they don’t know why.
Which is literally the exact same thing as "correlation is not causation".
Yeah… doctors recommend supplementing vitamin D if you don’t get much sun. This almost feels comedic.
Did the study not control for confounding factors?
It did, they state that right in the summary.
But they don't necessarily say what those confounding factors are in the abstract (I'm assuming they do in the full paper but I don't have access).

It's easy for me to imagine tons of confounding factors that are associated with vitamin supplementation, e.g. wealth (wealth is associated with better health outcomes nearly everywhere you look), diet in general, exercise levels, etc. I highly doubt they accounted for all of these.

Doctors recommend supplementing vitamin D if you have a measured deficiency. Most people naturally settle to 20 ng/mL or higher, and just incidental exposure, or eating certain foods can help you either absorb or synthesize it.

There are also people, like me, who no matter what, we can't make as much vitamin D for whatever cluster of genetic factors causes that. Some of us are always tired unless we take 50,000 IU of D3 a week.

That’s over double the dose considered “safe”. Obviously, I’m not suggesting you do otherwise; it’s just way outside the bounds of what most adults would do unless directed to by their physician.
For context, this study found that 30 minutes of midday summer sun exposure in Oslo, Norway was equivalent to consuming 10,000–20,000 IU of vitamin D.

https://www.ncbi.nlm.nih.gov/pubmed/19667143

Must be much higher in sunnier regions.

The neat thing about vitamin D synthesis in the skin is that it stops once there's enough of it - it is literally impossible to overdose on vitamin D through sun exposure. So, there's a ceiling that makes "must be higher in sunny regions" far from obviously true!
What happens to unused vitamin D consumed from supplementation?
That gets stored in the fat. Overdose through ingestion is a thing, our bodies aren't so smart about that; it's skin synthesis specifically that limits itself.
How much causes overdose?
I’m prescribed 50,000 3x a week. The RDA was possibly miscalculated, but the only real way to know what will work for you is test - dose - test, repeat.
People who avoid the sun are less likely to care about health overall and therefore less likely to take vitD supplements?
I don’t have access to the full paper, but I would expect that they at least tried to control for sun exposure.

In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

They probably have, but that doesn’t mean they have the necessary data to actually address the confounds. Often there is a trade off between what is most provable and what is most novel. Publishing incentives being what they are, novel invariably wins.
> safe assumption that professional researchers thought of it too

Research should be able to stand up to scrutiny. The scientific process depends on it.

Given the ongoing reproducibility crisis and plethora of garbage research coming out of academia, I’m not assuming anything about any research I see.

> In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

I work in academic medicine. I read a lot of papers. This is not at all a given in my experience, except maybe in the tippy top journals (Nature, NEJM). When in doubt, read the paper, see if they mention the confounder you thought of.

>it’s a safe assumption that professional researchers thought of it too.

It's a safe assumption that they though of it

BUT

Testing for it and getting useful data of something like a survey is a different story.

For example for a thing like that a survey could do more harm than good if the principles aren't really strict.

It wouldn't surprise me that some researchers could have just ignored not measurable data like that for the analysis. (staring if ofc)

Not even NEJM:

Recent letter to the editor in NEJM about that paper that showed 90% drop in Covid-related mortality after the first booster:

https://www.nejm.org/doi/full/10.1056/NEJMc2306683

It turns out that there was also a similar non-disclosed drop in non-Covid-related mortality. Either we discovered a magic elixir, or the entire effect is probably just confounding.

The original authors even say in their response that

> However, boosters were generally not administered to hospitalized patients who were at high risk for death from any cause.

They never even attempted to control for it.

Edit: at least NEJM accepts letters to the editor about the crap it publishes.

Or, at least, a safer assumption: it's worth checking to see what they said about it before publicly speculating.

And indeed, it seems they did survey for sun exposure and include it in their analysis, and they caveat a lot of their references to other work in their introduction noting where other studies didn't.

https://www.naturalhealthresearch.org/wp-content/uploads/202...

> Or, at least, a safer assumption: it's worth checking to see what they said about it before publicly speculating.

This would immediately kill about half of the comments on any research article posted to HN.

or publicly speculate and let a commenter who is more worried about checking check for you
I'm pretty sure XKCD created a name for this, if no-one is replying, give a horribly wrong solution to nerd snipe someone to put the time in to giving a correct solution.
The irony here is not lost on me, but it's Cunningham's Law (apocryphally named after Ward Cunningham, the creator of the first wiki software).
You were supposed to say it was greensupun’s 10th or something.
Ok but they tried to control for sun exposure just by asking how much sun exposure have you gotten in your life? A little or a lot (paraphrasing)?

The issue with this is that the amount of vitamin D someone might take is correlated with how much sun exposure is available. And the amount of available sun exposure can impact what is considered a little / a lot to each person.

Read the methods section of the study.

> The issue with this is that the amount of vitamin D someone might take is correlated with how much sun exposure is available. And the amount of available sun exposure can impact what is considered a little / a lot to each person.

That could be case but not necessarily in this study.

The study is based on a couple hundred people in a city in Finland, they could at least have tried to collect data on people closer to the tropics to hedge a bit. I doubt this has any validity ignoring such a basic confounding factor like living in a place that does have a lot of sun exposure.
Keep in mind that people from Finland are more likely to have skin that makes them particularly vulnerable to Melanoma.

A loved one is fighting this right now - if something simple like supplements, dietary practices or drug development could reduce the risk, it could potentially prevent alot of suffering. Even if it doesn’t work, perhaps it’s a line of inquiry with some value.

They could at least try to include white people in places where there is more sunlight, both my mom and my wife are white (my mom would likely be at home at a Nordic country, her family is full of redheads) and they both developed melanoma in northeastern Brazil, albeit they were found out quickly and did not cause much trouble.

Not even trying to consider the confounding variables is really sad.

Sure.

Honestly I’m don’t feel qualified to evaluate the study.

It attracted my attention because the risk factors for melanoma are different than other skin cancers. A smaller number of severe sunburn incidents is correlated with melanoma while ongoing exposure to more moderate sunlight drives other cancers. We already know that the palest skin types (ie your redhead relatives, etc) are at higher risk than even slighter less pale people.

I hope there’s more research and we learn more about ways to help bend the risk curve.

I haven't seen an image of an Alot of Suffering but it doesn't sound pleasant.
Accounting for confounders is hard. Otherwise randomised controlled studies wouldn't be needed, and we'd not have taken this long to walk back the consensus that red meat causes cancer.
Tweedledee: People with less sun exposure both intentional or unintentional may supplement more.

Tweedledum: Low Vitamin D weakens your immune system. Having a weakened immune system increases your odds of skin cancer.

I think just as likely is the general problem of people who take supplements being generally more conscientious and less likely to engage in risky behaviours (e.g. wearing sunscreen in summer)
Or they are supplementing because they don't get much sun to begin with
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Yeah my immediate thought too. Give 2500 rabid tanners vitamin D and let’s look at skin cancer rates in 10 years vs the population of rabid tanners.
I assume the rabies will get them first
Here is the description how they measured the impact of sun exposure to the results:

> The exposure of skin to UV radiation was clarified with different questions. The self-estimated lifetime exposure was studied with the following question ‘How often have you exposed yourself to sunlight during your lifetime?’ The answer options were (1) ‘seldom’, (2) ‘occasionally’, (3) ‘often’, or (4) ‘very often’. The sunburn history was studied with the following question: how often has your skin been burned due to sunlight during your lifetime? The answer options were (1) ‘seldom’, (2) ‘occasionally’, or (3) ‘often’. The answer options for the question of ‘Main environment in working history’ were (1) ‘outdoor’, (2) ‘indoor’, or (2) ‘variably both’.

They saw approximately the same distribution of sun exposure across the different test groups, it looks like.

I wish they asked exact rates and timelines. Like living in Florida, getting a bad burn only once per year might be considered seldom. But if you lived in Alaska, I’m sure that would be qualify as often.
Conversely, those people who refuse to ever cover up "cause you need vitamin D".
Or people that frequently supplement vitamin D live in places where there isn’t much sun hence the supplements.
So do people who live in high latitudes where there is very little sun in the winter and it is too cold anyway to reveal enough skin.
Unfortunately I cannot get full article access, but from the abstract it sounds like they did not control for actual sun exposure.

It would seem to me that those who self medicate with vitamin D are those who know they do not get sufficient sun exposure, and would necessarily also be those at reduced risk of melanoma.

I was told recently that US Doctors have lost their license over this topic; no idea if that is true.
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For a long time, the Mayo Clinic claimed vitamin D supplementation to combat SARS infections had no scientific proof and was possibly dangerous.

If such an authoritative source claims pseudo science and danger, your annecdote could very well be true.

Low vitamin D reduces correct responses by the immune system, and contributes to autoimmune disorders and results in higher possibility of infection.
It's not a surprise that fundamental health improves outcomes against novel infections. Public health should be encouraging significant evidence-based habits routinely.
No. My memory of the news stories were that some doctors preached it as a miracle preventative/cure, which let to patients neglecting other more effective preventatives because they thought they were safe from getting sick.

I think any doctor would tell you to take supplements if your lab tests showed that you're low. There's nothing controversial in that advice.

source: recently retired US Registered Nurse
A retired nurse passed you a rumour about a license revocal, a publicly-documented process. Instead of asking for evidence, you repeated the rumour and then tossed in a CYA disclaimer.
I doubt it. Michael F. Holick is probably the biggest vitamin d proponent and he has gained notoriety for having received a lot of money from companies making vitamin d supplements, as well as having done some wild stuff, such as defending abusive parents in court on the theory that children's broken bones are a result of vitamin d deficiency:

> In one case of a child who had suffered broken bones in which Holick defended the accused parent, the child later went on to suffer severe brain injury, for which the parent has been indicted.

as well as this interesting theory:

> Holick has speculated that the dinosaurs may have died of rickets and osteomalacia caused by a lack of vitamin D in reduced sunlight

https://en.wikipedia.org/wiki/Michael_F._Holick

and the only repercussion he has faced was the place he works not allowing him to treat children anymore.

If he hasn't had his medical license revoked I doubt any doctor simply recommending vitamin d would have theirs revoked.

My wife’s OBGYN endorses homeopathy. You have to kill someone or question covid vaccines to lose your license in this country.
I can only read the abstract, but this doesn't look very solid at all. It's a self-reported non-randomized study, and an absurdly large number of participants has had some type of skin cancer (184 out of 276). This makes the results extremely susceptible to selection bias.
I think by "at risk" they mean they are doing an intentional selection bias on probable skin conditions and it really isn't meant for conclusions..
Vitamin D is also readily available in food. You can get plenty by eating brown portabella mushrooms. I often read sunshine vs supplements discussed, and rarely food sources.
Vitamin D isn't in high enough sources in foods. Not unless you're eating a ~cup of them a day or in the days you aren't taking the supplement. This is important because the study went into differences between "occasional" and "regular" vitamin D supplement users.

Mushrooms are very good for many other reasons and should be a staple in most weekly diets.

I see research on essential vitamins all the time on HN. It really makes you think. There's cohorts who will debunk the studies based on methodology or glaring flaws. There's cohorts who will provide anecdotal evidence in support. There's even cohorts who will bring up a history lesson/"conspiracy" we all forgot about.

It really makes you wonder about essential vitamins though. There's so many of these types of studies that continue to show benefits of getting the right amount of vitamin D, but there's equally enough noise to tell you that you don't need it.

But for countries like America, experts continue to weigh in that we don't get enough essential vitamins and minerals through our diets, so wouldn't it just be common sense that many people are deficient and therefore should supplement?

Wasn't this the entire controversy of Pauling for example when he pushed Vitamin C? That the RDA amounts are not enough and should be highly personalized?

https://www.ncbi.nlm.nih.gov/books/NBK56068/table/summarytab... (Recommendations)

https://www.nature.com/articles/s41430-020-0558-y (Deficiency Worldwide)

I think it's absolutely bonkers - it really blows me away - that we have such debate on the effects of single molecules, studied for untold millions of human hours.

And yet many people think we can improve on nature; tinkering and toying with vastly more complex machinery and life, that we barely understand.

We are still discovering entire structures in the human body, ffs, yet are seemingly happy to allow vast monocultures of corporate and for-profit GM crops; 'trusting the science'.

The lies are as thin as our topsoil's gonna be soon. I love the idea of scientific progress, and understanding things, but this attitute of 'trust the men in white coats with everything even though we don't understand Vitamin C or D all that well' is truly mind-boggling.

*: I assume the people down-voting this think I'm talking smack on science - read again. I'm talking about scientism, and hubris, and appeals to authority. Which if you were paying any attention whatsoever the last 3 years you ought to know are big problems right now.

> we have such debate on the effects of single molecules

Most complex systems have simple limiters, almost by definition of the latter. You don’t need to solve fluid dynamics and combustion physics to understand that more air through a carburettor causes an internal combustion engine to run faster.

But we don't understand the effect of Vitamin C, or D. Your analogy is deeply flawed. We understand engines well enough, but we don't truly understand the machinery of even a single cell of our body.

We have broad strokes - take C for a cold. Take D in winter. But there are trained scientists who disagree with even these statements! We have people making a mockery of Nobel Prize winners over it! Where have you ever seen such debate about combustion engines.

> we don't understand the effect of Vitamin C, or D

Sure. But we know they are important. Despite being “single molecules.”

> We have broad strokes - take C for a cold. Take D in winter. But there are trained scientists who disagree with even these statements!

Because they appear unsubstantiated. You’re describing treatments. That’s a different ball game.

> We have people making a mockery of Nobel Prize winners over it

Pauling did not win his Nobel for vitamin C.

> Sure. But we know they are important. Despite being “single molecules.”

The point is that there's huge debate on how they work, why they work, whether they work for this and that, etc, despite them being about as tiny and simple in form as you could ask for.

And as far as I know no one has ever claimed that Vitamin C and D are not single molecules, so I've no idea why you put that in quotes. It's relevant that they're not, for example, the mixture of hundreds or even thousands of synergistic and antagonistic compounds, in various quantities, found in every single plant.

> Because they appear unsubstantiated. You’re describing treatments. That’s a different ball game.

Taking C for a cold, or D in winter, is NOT unsubstantiated - there are studies that show effect, and studies that show no effect. It's debated. That's exactly my point, that even these simple and tiny molecules inspire massive confusion and debate. It's in no way like an engine. The body and how it processes things like vitamins is so, so much more complex.

You can say this same thing about thousands of molecules and simple substances, which the scientismic community stands behind despite huge debate - SSRIs, anti-psychotics, glyphosate, etc. We don't understand them, and vested interests in white coats want us to believe otherwise. Remember tobacco being promoted by doctors? It wasn't that long ago.

The point, again, is this: that if we can have so much uncertainty about such tiny and simple things, why would we believe it's safe to muck about with our food supply (GMO monocultures), or to declare glyphosate safe and cover the planet with it, or claim that mRNA vaccines are utterly harmless (despite immediate evidence to the contrary, as now proven beyond doubt). Remember CFCs, PFAS, thalidomide?

These things are fundamentally different from your example of a simple combustion engine. They're complex on a level far beyond our current ability to comprehend. Even if we think we know what's going on, we really, really don't. We have hints, we have hunches, we have incomplete models with giant and dangerous holes in.

Two points:

> experts continue to weigh in that we don't get enough essential vitamins and minerals through our diets

First, would be better to list some specifics rather than "experts say". But even if so, saying that people don't get enough of some micronutrient X from food, it doesn't necessarily follow that supplementation with pills will lead to better health (except in some specific and extreme circumstances that rarely affect people these days, e.g. scurvy).

Second, this was not the entire controversy around Pauling's vitamin C fantasy. His recommended doses were orders of magnitude larger than recommended amounts - it wasn't just about being "more personalized". Nevermind that Pauling's vitamin C theories have been thoroughly disproven.

1. No, because the specifics change every week. One week you're deficient in fiber, the next Vitamin D. Look to the mainstream news or online articles for this ridiculousness.

2. Maybe consider looking at modern research. https://www.cancer.gov/research/key-initiatives/ras/ras-cent...

> Nevermind that Pauling's vitamin C theories have been thoroughly disproven.

Nothing in science is proven. Only re-evaluated.

The funny thing about the link that you give is that the hypothesis around intravenous Vitamin C is literally the exact opposite around Pauling's beliefs of oral vitamin C.

That is, taken intravenously, Vitamin C generates free radicals like hydrogen peroxide that are particularly dangerous to cancer cells. This is the exact opposite of oral administration of Vitamin V where it acts as an antioxidant.

Maybe read his book so you can hear what he has to say about it rather than your interpretation of it.

Anyway, the article I linked summarizes it fine too:

> So why did the Pauling and Mayo Clinic trials have different results? There are at least two crucial differences. First, the Mayo Clinic trials abruptly stopped the ascorbate administration, switching to traditional chemotherapy, when the patient developed signs of tumor progression. Thus, the overall median time of vitamin C treatment under the Mayo Clinic trials was only 2.5 months, while the Pauling and Cameron trials treated patients for the duration of the entire study period or as long as 12 years. Secondly, the Mayo Clinic trials administered 10 g of daily ascorbate to patients only orally, while the Cameron and Pauling trials administered their vitamin C both orally and intravenously. This difference in the two dosage routes proved highly consequential.

One issue with supplementation is the food matrix effect - Yes, Vitamin deficiencies are associated with all kinds of badness, but just supplementing this one nutrient doesn't address the underlying problem and often doesn't improve clinical outcomes. Rather, the deficiency is an indicator of poor health satus and to be fixed by adjusting the dietary pattern.

That's the thing with a lot of vitamin d and c associations anyway.

Use of vitamin D supplement is also probably correlated with sunscreen use. That is, health-conscious people use both.
I wouldn't doubt it. I'm in both cohorts. (Family history of malignant melanoma, fair skin, and moles and freckles.)

Most men never use sunscreen, including those who spend a great deal of time outdoors. I seriously doubt that cohort takes vitamin D.

I don't know; vitamin D supplements may be mostly advised in places where there just isn't enough sun.

In Scotland we get insufficient sunshine to produce natural vitamin D for around 6 months of the year, and there's discussion about whether everyone should be supplementing to the point it's been mooted as an addition to the water supply.

That's relevant because nobody uses sun screen during those months. I wouldn't expect any kind of correlation through sheer lack of use.

Like most nutrition/diet studies it's entirely correlational. Equally likely that people who take Vitamin D also just take better care of their health in other ways like just using sunscreen. Maybe it is true but it's so hard to draw any conclusion from a study like this.
People saying recent sunscreen use is a confounding variable may not be aware that the major cause of melanoma is childhood sun over-exposure.
These studies have no value.

There is basically no legitimate insight on things in medicine that kind of work (you need very stringent measures for lack of bias, huge varied cohorts, lots of studies, major controls, etc.) so, to this day, most studies on supplements/vitamins are low quality and highly inconclusive.

Things that have a huge effect are much easier to study, but that type of fruit is mostly picked by pharmaceutical companies and patented.

After years, many, many, many studies, billions of dollars, huge cohorts, lots of analysis, the medical industry can say that vitamin d supplements maybe possibly are helpful for some things but could also be harmful, but probably aren't, but also probably don't help unless you're very deficient.

https://www.mayoclinic.org/drugs-supplements-vitamin-d/art-2...

When you start talking about other supplements, you go into crazy-world.

It's not even clear that most pharmaceuticals do anything unless the effect size is very significant.

I've been sunbathing consistently this season for 30-45 minutes 2-4 times a week as weather permits. Recently got my D level tested to see how it has been working and it came back at 51.6ng/mL - pretty happy with this result.