The worthlessness of Vitamin D is mildly exaggerated

by surprisetalk • 30 days ago

385 293 30 days ago

cpncrunch• 30 days ago

Even so, it still seems to be a small effect. The author mentions some studies looking at sunlight vs all cause mortality. These, and more recent studies [1] found much higher reductions in all cause mortality from sunlight exposure, of about 30%. It's thought that other factors may be behind this, such as NO production in the skin in response to UV [2].

[1] https://pubmed.ncbi.nlm.nih.gov/32918215/

[2] https://karger.com/bpu/article-abstract/41/1-3/130/328295/Su...

Aerroon2• 30 days ago

Sunlight would likely get you all the "red light therapy" effects too.

nilirl• 30 days ago

I like this author but this post was only weakly intriguing.

More importantly, I'd like to know how long it takes to write a post like this.

Everything I write, I try to research and publish in under 2 weeks.

This post looks like it grew over time. I like that quality very much.

dynm• 30 days ago

I'd like to know how long it takes to write a post like this.

In this case, about three weeks.

amanaplanacanal2• 30 days ago

I suspect that blood vitamin D is mainly a marker for how much outdoor exercise people are getting, and that it is the exercise rather than the D which is causal.

fragmede• 30 days ago

But then why do we see improvements in people that get vitamin D + K2 supplements and not exercise?

amanaplanacanal2• 30 days ago

As the article mentions, we pretty much don't see improvements with supplementation.

warmedcookie• 30 days ago

Yeah, I wish the article had brought Vitamin K2 into the mix since that seems trendy to pair with your D3 these days.

written-beyond2• 30 days ago

My life changed after I got tested for vit D and started talking supplements. I was severely deficient. I am now sufficient and everything changed for me.

tweakimp• 30 days ago

What exactly changed?

heisenbit• 30 days ago

In December by chance I put a pack of Vitamin D into my shopping basket. I did not think much, thought to take 1000IE but then decided that for the first week I take 3000 to catch up. Muscle pain went and control over eating improved. I did not expect any changes based on past experience with 1000 but this time I could not ignore it (age can play a role) and I stayed on 3000. Tests a month later showed I was just not deficient any-more. I continued on the regime and started having improvements in long running skin issues to the extent my dentist noticed. It may not be a miracle drug but one should not underestimate cumulative impact individual factors, age and lifestyle changes (less sun) that may change levels and demand.

legitster6• 30 days ago

That doesn't undermine OP's point. Being deficient is unhealthy. But that doesn't mean an overabundance makes you healthier.

wafflemaker2• 30 days ago

I used to take 4k IU + K² and think that I'm covered, since 4K units was a lot.

I landed on just above deficient when tested.

My wife was on kind of same regime, but didn't follow it very strictly. She was deficient, but not extremely.

It was quite surprising, because I got warned when buying 4k unit tabs that they were quite strong and pharmacy clerk suggested taking less.

adamredwoods• 30 days ago

I am deficient, too, and take supplements (rare liver disease).

I wonder if taking mushrooms soaked in the sun improves absorption compared to supplements?

PierceJoy• 30 days ago

How do you know the changes aren’t placebo?

kvgr• 29 days ago

2 years ago i caught some repeated strep throat infection, repeated like 6-8 times - because my original general doctor said that with low CRP there is no way i have bacterial infection... before i found a doctor who finally did proper swab and ABTs - but i was so far gone that i got horrible headaches, muscle pain, stinging, absolute weakness... on top of that i cought covid and proper flu. Totally crazy, when they did mi vitamin D it was at 10% of minila recomended value. I god vit D and some immunity pills(pigs blood cells - this is questionable). I was slurping the vitamin D every day and in couple of weeks I was almost back to normal.

I have seen neurologists, imunologist, infection diseases specialist, everything is boreliosis qack and even somatic doctor...

Funny thing is before i got sick i spent 3 months on tenerife, so no reason for me to have low vit D. But it was probably depleted by immunity trying to fight the repeated infections.

so yeah, get your vitamin D checked if you feel weak, low on mood or anything out of zen

nextos• 30 days ago

Keep in mind vitamin D is really, among other things, an immune signaling molecule.

So, we know the mechanism, and it's quite plausible that supplementation works.

In other words, as an skeptic, I don't think it's just an epidemiological correlation.

mantas• 30 days ago

It depends on one’s whereabouts and kind of exercise. Exercising in a gym or outside with all your skin covered won’t make much vitamin D.

smt88• 30 days ago

Maybe this is true if you’re only considering white people. Brown people can spend a lot of time outdoors and still be deficient, especially if their ancestry is from much a much sunnier region or lifestyle than the one they’re currently living in.

petesergeant3• 30 days ago

Indeed: “Vitamin D deficiency in western dwelling South Asian populations: an unrecognised epidemic” … “27–60% of individuals, depending on season”

https://pmc.ncbi.nlm.nih.gov/articles/PMC7663314/?utm_source...

kevin_thibedeau• 30 days ago

It has never been established that darker people require the same amount of D as lighter. The supplement industry plays on these fearmongering to boost sales.

legitster6• 30 days ago

Ding ding ding.

People who are drawing blood and trying to find some correlation between vitamin presence and health at this point are just practicing divination. The fact that it can be published in a scientific journal without any sort of RCT to back it up is palpably unscientific.

The customers of these studies are the supplement companies looking for another product to sell.

kccqzy• 30 days ago

I also suspect that the frequency of outdoor exercise matters even if the total duration of outdoor exercise remains the same. Subjectively, I feel much healthier when doing thirty minutes of outdoor exercise six times a week, than when doing one hour of outdoor exercise three times a week. But then of course, all the causal effects could have been caused by a different factor (say dopamine release) than vitamin D.

systemsweird2• 30 days ago

Bingo. Obviously being deficient is bad, but the reason supplementation seems unimpressive is this is one of those proxies for healthy lifestyle. Kinda like how grip strength is correlated with longevity but banging out tons of hand gripper sets isn’t going to do much for you health.

Aurornis2• 30 days ago

This is a refreshingly balanced and honest analysis of Vitamin D studies.

The strongest evidence for Vitamin D is in people who are severely deficient. Bumping up to a normal range can provide some improvements.

The health influencers started noticing that the Vitamin D studies coming out weren't matching their original hype for Vitamin D, so many pivoted to trying to make claims that most people are severely deficient and just don't know it, which provides a convenient out to dismiss the studies that didn't pre-filter for people who were severely deficient. You can find waves of people on social media repeating the idea that almost everyone is Vitamin D deficient and encouraging high dose supplementation still.

Speaking to a doctor who runs Vitamin D labs as part of her annual physical screening process, she's now actually seeing more people who have excess Vitamin D than too little Vitamin D. Upon followup she discovers that patients have listened to a podcast about Vitamin D and started taking it regularly, unaware that they're pushing their levels into the range where it can start doing more harm than good.

Vitamin D is tricky because it lasts for a very long time in the body, which means steady-state supplementation can take a very long time to stabilize. I suggest anyone supplementing for a long time get a blood test, which can be ordered without your doctor if you can't get your doctor on board.

On another topic: Fish oil has also gone through a similar cycle of being hyped up based on early results, with higher powered follow on studies showing much less interesting results.

thaumasiotes• 30 days ago

The health influencers started noticing that the Vitamin D studies coming out weren't matching their original hype for Vitamin D, so many pivoted to trying to make claims that most people are severely deficient and just don't know it, which provides a convenient out

Not really. It isn't possible to be severely deficient in vitamin D without knowing it. By definition, if you are severely deficient in vitamin D, you have rickets.

dyauspitr• 30 days ago

On a slight tangent, if people are unaware, you can pay for and get just about any lab test without a prescription in the United States.

nomel2• 30 days ago

This is how I found my 10k IU of vitamin D a day, based on modern recommendations for indoor workers, that I modulate based on how much I'm outdoors, was perfectly on the mark!

jvican2• 30 days ago

Yes, and to be concrete, you can do so at economical prices at https://requestatest.com (it's a lifesaver in many occasions, I've used it 4 times with great success).

Tangurena2• 30 days ago

My PCP uses Quest Diagnostics and a vitamin d test is, I think, about $50. No fasting needed for it, nor prescription.

petesergeant3• 30 days ago

You can get most tests (although often not genetic) in many countries, with Canada being an outlier in forcing you to get a doctor’s note for just about everything.

sbayg• 30 days ago

Baby aspirin was overdone too. Interestingly, the fish oil hype cycle has a much longer timeline if you consider the popularity of cod liver oil once upon a time.

nostromo3• 30 days ago

Cod liver oil wasn't hype, it was needed in norther climates to prevent rickets.

It was taken for its Vitamin D, not for its omega 3s.

yoyohello132• 30 days ago

It's pretty safe to assume all hyped supplements are pointless. Being generally active and eating fruits/vegetables is like 80% of the work for being healthy.

almost everyone is Vitamin D deficient

This was the red flag that made me realize it was BS early on. If everyone is deficient, then it must not be that important.

crazygringo• 30 days ago

Being generally active and eating fruits/vegetables is like 80% of the work for being healthy.

Except for the things that you get from sunlight, not diet.

If everyone is deficient, then it must not be that important.

But nobody who lives in e.g. East Africa and spends a lot of time outdoors is deficient.

So it's actually pretty reasonable to say that a modern indoor lifestyle combined with long winters would truly lead most people in those regions to being deficient.

ewild• 30 days ago

Pretty much the only one with a real consensus around it is creatine. And even that has debate around the right dose

robocat• 30 days ago

is like 80% of the work for being healthy

I would suspect you're a man under 60.

I don't think your statement applies to the elderly (e.g. my mum needing D and Calcium for osteoporosis).

And I've seen many active healthy female friends under 60 actually need suppliments (I'm ignoring the stereotypical yoga worried well): plus pregnancy or health issues have an impact too.

But maybe I'm a victim of sampling bias since the men I know seem much less likely to see a doctor.

ChadNauseam• 30 days ago

If everyone is deficient, then it must not be that important.

Most people are overweight. Does that make being a healthy weight not that important?

Grombobulous2• 29 days ago

Being generally active and eating fruits/vegetables is like 80% of the work for being healthy.

I suspect that a relatively low percentage of people in a solid number of wealthy countries meet these qualifications.

If everyone is deficient, then it must not be that important.

This isn't sound logic. Something being common doesn't make it unimportant or less of a problem.

SOLAR_FIELDS• 30 days ago

The moral of the story here is just to do bloodwork on a regular basis (absolute bare minimum once a year) and respond accordingly. I take some supplements like vitamin D, but I only take what is empirically measurable. If I can't quantitatively measure the outcome, then there is no value and it's a woo woo solution. This isn't always going to be the best advice, but a vast majority of times it will be.

andruby3• 29 days ago

My family runs a blood analysis lab in Belgium for which I wrote some of the statistics gathering software.

The thresholds for 25-OH vitamin D: <20 ng/mL → deficient, 20–30 ng/mL → insufficient.

When I looked at all 1738 blood samples that had their Vitamin D tested between Feb 1, 2020 and Mar 13, 2020 (We were looking into the link between Vitamin D and COVID-19): The median (P50) was 20.1 ng/mL and the average was 22.4 ng/mL. Standard deviation: 11.24 ng/mL Half the samples were deficient, and the next 20% was insufficient.

Coming out of winter in Europe in a country with limited sunshine: most of the population is deficient in Vitamin D.

Histogram: https://files.catbox.moe/p785wx.png

vintermann• 29 days ago

Worth noting all the three big studies mentioned in the article were on Americans.

dizhn• 29 days ago

What do you think about the thresholds themselves? How often are they updated usually with new research?

bluenose692• 29 days ago

The curve on your diagram makes me think that you've fitted a normal (Gaussian) curve to the data. By eye, the distribution looks a bit more like log-normal, and so if you're still working on the data, you might want to try that to see. Not that anything you've said or concluded seems wrong, though.

noduerme• 29 days ago

The Mediterranean diet itself has a lot of health benefits interrelated with the ones claimed about fish oil.

But just as a human experience, the first time I ate cod livers, it was hard to accept. Then I started spreading them on toast for breakfast, and realized that they were quite delicious, but very very much an acquired taste (and I eat almost everything).

As far as Vitamin D, there does seem to be a correlation between deficiency and severe coronavirus disease

https://www.mdpi.com/2075-1729/15/5/733

[edit] to say, I love chicken and cow liver, but it took awhile to get a taste for fish liver. Pork liver, however, is putrid. I don't think I could eat that again.

Filligree• 29 days ago

The Norwegian way to eat cod liver is “squished between two flatbread, mixed with boiled potato and also cod”.

Which is absolutely delicious, even for a kid; it’s one of the meals I still remember loving. You should try it!

wongarsu• 29 days ago

Seemingly any decent way to tune in a steady-state supplementation involves multiple iterations of the "get blood test, adjust dosage, repeat" loop

On the other hand, when our body synthesizes Vitamin D itself it seems to regulate that process to prevent overdose. So I've just settled on supplementing in the winter based on my best estimate of the correct dosage, then let my body do its thing in the summer. No issues so far, and supplements have had a major impact on my fatigue/energy/depression levels in the winter

seba_dos12• 29 days ago

You keep showing up under articles about vitamin D and keep telling that more people have excess than insufficient vitamin D levels without presenting any data whatsoever.

We're among plenty of inside-dwelling nerds here. Do the test. Don't listen to folks like the parent, don't let yourself be discouraged; check your blood level and act on it if necessary, it's fast and cheap. I even had a test done at my home, you can schedule that online these days! You're much more likely to be severely deficient than have it in excess (it's quite hard to get to toxic levels anyway, you'd need to be really irresponsible about it) and once you confirm that, supplementing can help you tremendously with plenty of mental issues you may be experiencing. It won't fix you up, but it can make it possible for you to fix yourself up in the first place. And if the test shows you have adequate levels already - good for you.

(and if you're too depressed to even arrange the test, it may make sense to start supplementing blindly - but don't exceed ~10K IU D3 daily and make sure to stop after 2-3 months tops. Hopefully at that point it'll be easier for you to finally do the test to know whether to continue or not; don't keep taking high doses blindly, toxicity is hard but not impossible to achieve and you really don't want to be suffering from it. You almost certainly won't reach it with 10K IU when starting from deficiency, but it you happened to be on the high side already at the start it could be dangerous when prolonged)

tbugrara• 27 days ago

Mind sharing what "higher powered follow on" studies (not even sure what this means) showed less interesting results for omega3 supplementation?

fred_is_fred• 30 days ago

I didn't see any mention of K2 (or missed it) - but a lot of D supplements combine with K2 as a "traffic cop" to keep calcium in bones and not arteries. I've not found a ton of evidence on this either, but seems to be a popular combination.

brandonb3• 30 days ago

Another more recent trial (TARGET-D) is showing a 52% reduction in heart attack risk: https://www.empirical.health/blog/vitamin-d-heart/

That trial used a dynamically-adjusted dosage of a vitamin D3 supplement, where dosing was set as to keep blood levels within a target range of 40–80 ng/mL. IMO part of the reason this trial is showing better results than the previous clinical trials of vitamin D supplementation quoted in the above article is that vitamin D has bad effects if too low and too high. Adjusting the dose dynamically to achieve an optimal range gets you the benefits without some of the negative effects.

adrian_b5• 29 days ago

That blood level matches what the parent article cites as typical for Africans who were still eating their traditional food, and which is higher than typical for the industrialized countries.

rzz32• 30 days ago

Has anyone done a RCT of D3+K2? K2 seems to be important in the absorption of D3. Another aspect that bothers me with these studies is that we’re simply supplementing the vitamin D, seemingly without measuring the change in blood levels. I took 2000IU (+K2) a day for many years in between testing my blood levels and still had <30ng/ml and had to go up to 5000IU/day. I’d like to see some further study.

nullc2• 30 days ago

I took 2000IU (+K2) a day for many years in between testing my blood levels and still had <30ng/ml and had to go up to 5000IU/day.

Likewise, 23ng/ml while taking 2000iu/day of dry vitamin-d.

Switched to 5000iu +K2 in MCT oil, -- 8 months later I'm at 64ng/ml.

rbjorklin• 30 days ago

Any noticeable difference how you feel health wise? Energy levels? Mood? Sleep quality?

icedchai• 30 days ago

I switched from 2000 to 5000iu about 8 years ago. My levels went up similar to yours, but I don't feel much different!

brandonb3• 30 days ago

TARGET-D is an in-progress study that supplements vitamin D based on blood levels (your idea).

nradov• 30 days ago

I think that study is already concluded but the results haven't been published yet.

https://clinicaltrials.gov/study/NCT02996721?tab=study

odie5533• 30 days ago

Were you taking hard tablets? And were you taking them with a fatty meal?

Those are both very important. I take a Vitamin D + K2 softgel with a meal that has some fat in it.

aaronbrethorst• 30 days ago

Costco sells D3+K2 softgels! Great price, of course.

I started taking them at the recommendation of my podiatrist after I broke my foot last winter (third metatarsal fracture, specifically, ouch).

amelius• 30 days ago

What I found was that I had to dissolve vit D under the tongue, not immediately swallow it.

cj2• 30 days ago

K2 is also known to prevent problems with calcium build up which can happen if Vitamin D is dosed too high. I personally would never take Viramin D without K2 alongside it.

fridder• 30 days ago

One problem: folks that are on blood thinners shouldn't supplement with vitamin k

trevorkoob2• 28 days ago

When I did my master's thesis on Vitamin D supplementation the conclusion was that vitamin D testing is wildly inaccurate, and we needed to have studies based on a target level - ideally one based around sub-saharan African community levels.

As for supplementation, sunlight has been estimated at providing up to 20,000IU per day, which I think (not medical advice due to the lack of study), from a mechanistic point of view, suggests an upper limit to daily supplementation.

OutOfHere3• 30 days ago

Just mildy exaggerated? Is this a joke article? If you don't achieve a suitable level, health will suffer immensely, even permanently. There are no ifs and buts. People who say otherwise work for the medical industrial complex and will get you killed.

Note that adequate magnesium is critical for proper vitamin D function, but the article doesn't document it.

gblargg3• 30 days ago

Same for breathing oxygen, if you don't get it you'll die, but for most people oxygen supplementation would not be worth even knowing about.

OutOfHere3• 30 days ago

That's an absurd analogy. Vitamin D is a vitamin that is in large part derived from significant sunlight exposure. Vitamins are essential by definition. Sunlight exposure is highly insufficient by historical standards. This is why supplementation is absolutely necessary in almost everyone who is not a full time outdoor worker.

In contrast, the air contains oxygen which is sufficient for most people with normal lung function.

legitster6• 30 days ago

Your body needs vitamins in order to form complex aminos to operate. But your body only needs to make so many of them - especially if you are an adult, not pregnant, or not suffering from a disease of some sort.

The very premise that loading up your body with "excess" vitamins beyond what you need is already pretty fraught. Building a house without enough lumber can lead to long term deficiency - but loading up a construction site with more materials than are needed shouldn't automatically be assumed to be good.

The reality is that the modern diet has already solved so many common nutrient deficiency diseases (pellagra and goiters were a shockingly common diseases 100 years ago) that maxing out on vitamin intake has become more of something like a speculative hobby than anything else.

UpsideDownRide• 30 days ago

Vitamin D deficiency entered the chat. It's a relatively common issue in many countries.

legitster6• 30 days ago

That's fair, but it also exactly explains why there are weak positive effects of extra Vitamin D.

There's a lot of unknowingly deficient people out there who get benefits from supplements. But the benefits are limited by the upper bound of the deficiency.

im3w1l• 30 days ago

Two things to consider: The recommended levels are established based on "good enough for 95% of people". That means that quite a lot of people can get by with less than the recommendation. Furthermore, being deficient is not a binary. If you are just a little bit deficient you may have very mild symptoms.

PaulHoule3• 30 days ago

Most vitamins are a cofactor for enzymes like

https://en.wikipedia.org/wiki/Thiamine#Biological_functions

Vitamin D is not but rather it regulates calcium and phosphorous metabolism.

torstenvl2• 30 days ago

loading up a construction site with more materials than are needed shouldn't automatically be assumed to be good

It is almost universally recognized as good to do exactly that. It's better to have one planned extra trip to return excess materials (if they can't be used on the next job) than to have multiple unplanned trips when you unexpectedly run out of this or that.

quickthrowman• 30 days ago

Definitely. I ordered material to replace the balusters on our shared family cabin with horizontal stainless steel cable deck rails and ordered 5-10% extra for all of the various fittings, cable, as well as a backup swage tool.

One of my uncles asked why I’m budgeting for an extra $150 of material we won’t need. I asked him how much it would cost to get us all up here for another weekend to finish if we needed extra parts. The answer was “more than $150” and he understood.

It’s even more crucial to keep enough material on the jobsite when you’re running a project and paying $140 an hour for an electrician.

systemsweird2• 30 days ago

You mean my DIY projects that result in a dozen trips to Home Depot aren’t optimal :)

gblargg3• 30 days ago

Depends on which vitamin as well. Some like vitamin B and C aren't retained, so excess is shed quickly.

asdff• 30 days ago

There would still be a ton of goiters if not for iodized salt, basically an obligatory vitamin intake. People had no good iodine source living inland where most anything they catch or grow is not going to have sufficient iodine no matter what it is they were eating.

I'm not sure what the ancestral iodine source might have been. Fishing villages perhaps along the coast? Hard to say how much coast was relatively populated given challenges of shifting shorelines and archaeological efforts. You can still reproduce laden with a goiter however, and that is enough to keep chucking malnourished humans somewhere on earth.

OkayPhysicist• 30 days ago

It takes a pretty extreme iodine deficiency to end up with goiters. In most environments, there's enough in the soil that eating local plants / animals that eat those plants supplies enough.

The iodine deficiency issues that haunted the Swiss (and Appalachia) arose from people settling down from nomadic lifestyles, in mountainous regions that easily were leeched of iodine by rainfall, and then farming that already leeched soil until there wasn't any iodine left at all.

cute_boi• 30 days ago

These days it is same with protein... Too much protein fads.

HerbManic• 30 days ago

Yeah, you do need daily protein but for most people nowhere near as much as they are taking in.

You see these protein bars and some of them basically have a full days worth of the stuff and that is before your other meals come in.

There is the YouTube channel 'Subway takes' where people have about a minute to argue a point of view, usually very funny takes as well. There was one that was 'The Protein fad is basically an eating disorder for men', they aren't far off the mark with that.

legitster6• 30 days ago

I think the difference is that increasing protein intake does offset other worse eating habits. So it's not that you need the protein, but there's a small probability that it replaces calories from refined carbohydrates.

throwaway2037• 30 days ago

    > Too much protein

Is there really a scientific consensus about "too much protein"? As I understand, the bit about "stresses your kidneys" has been disproven.

adrian_b5• 29 days ago

While there is no doubt that excess vitamin intakes are useless or even harmful, the problem is that for most vitamins there is a great uncertainty about which are the optimum daily doses, because the controlled experiments that would be needed to determine those doses would be rightly deemed as unethical.

Therefore, since we only have some weak circumstantial evidence, debates about how much vitamin D is good, and the same about other vitamins, will continue. As long as the uncertainty persists, it is safer to ingest somewhat higher doses of vitamins than those recommended, but not many times higher.

The conclusions of the article were that high amounts of vitamin D have been shown to be correlated with good health outcomes, but the supplementation studies could not reproduce the same outcomes, so it remains mysterious what factor was associated with vitamin D in the studies with positive effects and whether vitamin D itself had any role or its presence was just a coincidence.

criddell3• 30 days ago

This is great. I wonder if there's something like a patreon model where we could sponsor similar deep dives on other supplements?

For example, I've been supplementing with nicotinamide riboside for a few years now. I stop occasionally and when I do stiff and sore hands and knees return and I get more headaches.

I'd love to know if I'm deluding myself (placebo effect?) or there's good science that backs up my experience.

js2• 30 days ago

examine.com

criddell3• 30 days ago

Thanks!

The results from examine.com for nicotinamide are interesting, but not as focused or concise (or usable) as the vitamin D information in this posting.

merb• 30 days ago

For a while there, many people thought vitamin D was magical

I never heard that in Germany. I only heard that if you use certain medications like cortisone that vitamin d could be problematic. Most doctors will give vitamin d supplements when prescribing cortisone, at least in Germany.

holistio• 30 days ago

Just two borders away, in Hungary, I've heard plenty of "magical vitamin D" tales. Tired? Take some D. Depressed? Take some D. Leg hurts? Take some D.

I do take it in the winter, but I'm quite skeptical regarding the panacea hype.

Johnyjohnson123• 30 days ago

People who say vitamin d isnt important should read about auld rickie...

Aerroon2• 30 days ago

The survey in the article that assessed vitamin D deficiency was a bit odd:

Because physical exams are performed in mobile vans in NHANES, data could not be collected in northern latitudes during the winter; instead data were collected in northern latitudes during summer and in southern latitudes in winter. To address this season-latitude aspect of the NHANES design, we stratified the sample into two seasonal subpopulations (winter/lower latitude and summer/higher latitude) before examining vitamin D status.

Yeah, I'm not surprised that the rates for vitamin D deficiency were low.

Less than 1% of the winter/lower latitude subpopulation had vitamin D deficiency (25-OHD <17.5 nmol/L). However, the prevalence of vitamin D insufficiency in this group ranged from 1%–5% with 25-OHD <25 nmol/L /.../, even though the median latitude for this subsample (32°N) was considerably lower than the latitude at which vitamin D is not synthesized during winter months (∽42°N).

and the more northern latitude in summer:

With the exception of elderly women, prevalence rates of vitamin D insufficiency were lower in the summer/higher latitude subpopulation (<1%–3% with 25-OHD <25 nmol/L)

Now imagine if you lived in northern Europe around the 60th parallel, where the sun doesn't get high enough in winter to produce vitamin D.

qurren• 30 days ago

Not to mention, northern latitudes get more sun that average in summer, and most northern countries have more reasonable working hours so people actually do go outside.

HPsquared3• 30 days ago

More hours of sun, but it's less intense.

galleywest2002• 30 days ago

Could this be why evidence suggests that redheads synthesize Vitamin D more efficiently? Red hair is more prevalent at higher latitudes (I think).

Can redheads produce Vitamin D in these darker conditions while others cannot do so effectively?

https://www.sciencealert.com/evolution-favored-genes-linked-...

annzabelle2• 30 days ago

Pale skin in general helps synthesize Vitamin D. The less melanin you have the more you absorb, this is why lighter skin happens at northern latitudes. Darker skinned people are more likely to need to supplement it.

bostik• 29 days ago

Now imagine if you lived in northern Europe around the 60th parallel, where the sun doesn't get high enough in winter to produce vitamin D.

Like... all of Finland? And most of Norway?

Both countries where the answer to "when does the sun rise?" can be "at the end of January".

b112• 29 days ago

This is why you're supposed to fatten up in the summer. In nature, mammals fatten up all summer long, and fat soluable vitamins such as D, are stored in your fat.

As animals basically slowly starve over the winter, they consume their fat and also get some vitamin D back. It helps shore up the lack of sun in the winter.

normie3000• 29 days ago

data were collected in northern latitudes during summer and in southern latitudes in winter

And what were they doing for the other 9 months of the year?

PaulHoule3• 30 days ago

It's arguable whether Vitamin D is really a vitamin or a hormone, see

https://pubmed.ncbi.nlm.nih.gov/33549285/

Look at the molecular structure

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

that's a freakin' steroid with one of the bonds in the rings deleted

https://en.wikipedia.org/wiki/Secosteroid

brandonb3• 30 days ago

It's pretty well-established science now that vitamin D is a hormone, not a true vitamin. Vitamin D binds a nuclear receptor that regulates roughly 1,000 to 2,000 genes (5-10% of the human genome).

The "Vitamin D" moniker has just stuck around since it was named in 1922.

infinite_spin2• 30 days ago

Yeah, it's just a holdover, the term "vitamin" originated from "vital amine", and vitamin D doesn't even have an amine group

xutopia• 30 days ago

Just because vitamin D supplements helps with rickets doesn't mean supplementation helps all the other things we seem to attribute to vitamin D.

I think a good hypothesis for the discrepancy regarding why people with "naturally" high levels of vitamin D fare better than those who do not has to do with how vitamin D is produced naturally.

If you take the vitamin orally it might help for rickets and a few other issues but if you take it naturally via sunlight you might actually be having other benefits that aren't properly measured today.

With the current state of fear surrounding sunlight I doubt people are getting enough to see benefits and all studies use oral supplements instead of time in sunshine.

ninalanyon• 30 days ago

Because physical exams are performed in mobile vans in NHANES, data could not be collected in northern latitudes during the winter

Why not?

infinite_spin2• 30 days ago

Probably due to road conditions during the winter season. Imagine asking someone who isn't used to driving on icy roads to drive a large van full of equipment up through the Rockies

floxy• 30 days ago

They plow the mountain passes in the winter time in at least Montana and Idaho. I'd be very surprised if they don't in Colorado or Utah.

atahanacar4• 30 days ago

Medical doctor here. Please don't get health advice from hn comments. As a matter of fact, I advice against reading anything about health on hn, as the risks of dangerous misinformation far outweigh any useful information you might learn here.

kev009• 30 days ago

Halp us docter

annzabelle2• 30 days ago

There was a thread that touched on lyme disease recently, and there were a ridiculous number of comments going down pseudoscientific rabbit holes about people who'd somehow gotten chronic lyme in places with no endemic lyme disease and that the only ways to fix this were chronic antibiotics and hyperthermia chambers.

HN often suffers from the trait of people who are really bright in one area assuming that that means they are really knowledgeable in areas they don't know much about.

atahanacar4• 30 days ago

That is relatively benign compared to what I've seen before. I normally refrain from repeating misinformation, even for debunking it but I will make an exception (or two). I've seen comments ranging from "salt intake doesn't increase blood pressure because you pee what you don't need" to "blood glucose levels aren't good for diagnosing diabetes".

Edit: OK, that's not really a "range". I have no idea why I phrased it like that. Both are very dangerous statements that can be life threatening if the wrong person believes it. I just hope that comment didn't cause any diabetic ketoacidosis cases.

Bender2• 30 days ago

Principal Armchair Commander here. I second this. That said I also avoid health advice from professionals. I have too often found their incentives to be in conflict with my well being. I just do my own research and ignore everyone, especially AI.

atahanacar4• 30 days ago

I assume you are American? I find it sad that a doctor has any incentive other than providing their patients with the best care possible.

acheron• 30 days ago

It’s always great when years of medical and scientific studies are instantly debunked by HN’s top JavaScript developers. One wonders why we even bother having research universities.

cup• 30 days ago

Do you think people seeking medical advice from HN comments might be related to their disatisfaction from the suppor they receive from medical clinicians?

atahanacar4• 30 days ago

Yes and no. Some are just way overconfident in their knowledge of medicine and human body, while it is miniscule compared to the average physician's. Medicine is a field much larger than people realize. It is easy to think you know a lot when you don't even know how much you are missing.

Having a reason doesn't make it any less dangerous though.

pixel_popping• 29 days ago

I can't fully agree with avoiding the topic altogether. Yes, people need to be careful, but building real knowledge in complex subjects like health generally requires engaging continuously (same as in Computer science) with research and studies (and learning to evaluate them critically) AND gathering people' opinions and perspectives (very important, after all, the experience of an MD grows over time because of reports of side-effects from your own patient, which is close), rather than shutting out discussion entirely, even for yourself who is already an MD. Also not everyone had the opportunity or desire to study medicine formally but still want a chance to be able to understand it in greater depth, and one great way to learn is to read a ton.

We can also relate that some drugs (albeit most are illegal but whatever, it doesn't invalidate them) from recreational to bodybuilding drugs are practically only massively "studied" by the bro-science community and many topic about harm reduction and so-on stems from there, enormous amount of people have started getting interested into health, supplements... due to reading about it randomly from people.

Although, in practice, you are partially right, it also does damage because many people will just take it as face value and just don't have enough expertise yet to do a proper reasoning around some takes and might not check if it's factual.

vondur• 30 days ago

I was taking 4000IU of Vitamin D daily along with 100 mcg Vitamin K-2 MK-7. My Vitamin D level was 60ng/ml. I've since dropped down to 3000IU per day. I go outside a lot but am either covered or using sunscreen since I sunburn easily.

bethekidyouwant• 30 days ago

Pretty sure if you’re burning easily then you are making vitamin D easily so just go in the sun but not so much that you burn. (which is i think common sense)

persedes• 30 days ago

Not in the field, but every time vitamin D studies come up I am reminded of the one that called out how current recommendations are based on faulty math (confusion on how to combine different sized studies confidence ranges ) and miss the mark significantly (and a lot of studies are based on those recommendations...)

https://pmc.ncbi.nlm.nih.gov/articles/PMC5541280/

nostromo3• 30 days ago

To save people the click: the study says that the recommended vitamin D intake is much too low.

Etheryte2• 30 days ago

Honestly you don't even need to know the recommended number. In many countries you can get tested for free, and if that's not the case for you, getting tested usually costs in the ballpark of a box vitamin D supplements. Measure and only then supplement, then measure again later. You don't need to fly blind.

rendaw• 29 days ago

This has come up several times before. It's not well cited. I read through it myself and even if the math is right, the application of the math seems incorrect.

The original data was a small number of studies with a small amount of old (1980s?) data that found a slope with so-so correlation.

The revised math finds a much smaller slope with what appears to be much worse fit to the same old data. The data was nearly horizontal before, but after the math changes it's much further away from 0.

The original study was making predictions near the data. The revision is doing massive extrapolation, far away from the range of what any of the studies tested.

I'm not a statistician, but it's not surprising to me that it's being ignored.

burnte• 30 days ago

Ugh, more health pontificating from nonexperts. The blog is full of lame "hot takes." Blogspam, IMO.

jmhammond• 30 days ago

In case the author is here, you can find the Garland & Garland (1980) article on sci-hub.

And if link is allowed https://sci-hub.ru/https://doi.org/10.1093/ije/9.3.227

gwern• 30 days ago

I expect the author is aware of that: where do you think he got the graph from if there's only 'gated copies'? But Sci-Hub links are unstable even if you don't mind linking them.

elzbardico• 29 days ago

Linking to sci-hub for a known blogger may lead to undesired legal consequences in case the journal copyright mafia decides to make an legal example of you.

skyberrys• 30 days ago

The charts showing vitamin D not helping, but also slightly hurting make the topic more relevant. The title is almost too flippant of the conclusions which is don't just take more than necessary,because it's likely to actively cause harm not just slightly increase your vitamin D.

innocentoldguy• 30 days ago

Vitamin D is a lifesaver for me. I'm severely deficient, and if I don't take about 10,000 IU a day, I seem to get colds every five minutes.

nullbio3• 29 days ago

Have you tried going outside? Spend 15 minutes in the sun every day. It's not really that hard.

whycome• 30 days ago

Leaving out skin colour from the conversations while mentioning 'randomized trials' and 'seasonal subpopulations' is problematic. Vitamin D production is highly tied to skin colour (melanin levels).

d2kx2• 30 days ago

Probably heavily depends on the country/region, but here in Germany it is basically the norm to be Vitamin D deficient. Like, half of the population have a deficiency when there is some sun and basically everyone has a deficiency for months during fall/winter/spring. So I have to laugh when I read "taking vitamin D does nothing unless you’re severely deficient". Yeah like, but that's most people in many countries lmao

rhipitr• 30 days ago

Have a loved one that has extremely low vitamin D issues. Takes ergocalciferol from time to time and it is pretty useful in my opinion.

kazinator• 30 days ago

I experimented with D3 supplementation up to almost a decade ago. I made some HN comments about it [2018]:

https://news.ycombinator.com/item?id=17638508

I ultimately stopped it because it seemed to cause lower back aches. (Pretty sure, bone/muscle not kidney!) Every time I went on the D3, my back would start to hurt. That repeated several times, enough to suspect a pattern.

The cause may be similar to the itchy, tingling teeth.

According to this fascinating paper, Vitamin D can actually trigger the leaching of calcium out of bones, into circulation:

https://pmc.ncbi.nlm.nih.gov/articles/PMC8147670/

After the abstract, find the section heading "Vitamin D mobilizes calcium from calcified bone".

But that is in very high, pharmacological doses. Not your 5000 UI per day.

dashmeet• 30 days ago

Not medical advice.

You probably need to take vitamin d3 with k2 to avoid the calcium issues.

Edited to add link https://pmc.ncbi.nlm.nih.gov/articles/PMC5613455/

green_wheel• 30 days ago

I was told that there are lots of latitudes in North America where the sun is at too low an angle for your skin to make vitamin D for large parts of the year so you should take it during those times and then you should be fine during the summer if you get outside enough.

zhivota2• 30 days ago

Thousands of words and no mention of the obvious thing - testing whether sun exposure is beneficial or harmful.

The article opens with the observation that southern states had lower cancer rates due to solar irradiance. But then we intervene by taking pills. Why not try to absorb through the skin, even if it means something like a tanning bed?

chr15m• 30 days ago

Yep, it's sunlight.

Nobody will run that trial though because we've spent decades telling people the sun is dangerous and gives you cancer (both things can be true of course). Putting people in the sun every day would not pass ethics tests.

Also you cannot sell sunlight.

waysa• 29 days ago

Also you cannot sell sunlight.

Don't give them ideas.

jerlam• 29 days ago

There are many nuances and people seem bad at understanding those. Too many are getting their information from "health influencers" and 30 second videos, which is why we seem to bounce between the two extremes of "everyone should take Vitamin D!" and "Vitamin D is overrated!".

Australia has tried to explain sun safety here, taking into account that Vitamin D is best obtained from sunlight:

https://www.cancer.org.au/cancer-information/causes-and-prev...

zhivota2• 28 days ago

Yeah not bad, though UV index of 3 is pretty comically low. Here in Manila it's basically full cloud conditions.

I'd be interested to know a curve, i.e. at UV index 8, 3 minutes exposure, at index 6, 10 minutes exposure, etc. Maybe with a scaling for skin tone. It seems like either this kind of study has never been done (perhaps for ethical reasons) or else the information is not being disseminated. The latter seems to happen often in the medical space for paternalistic reasons, which honestly make sense for the broad public but it should be available for people to find who are motivated and have a deeper interest anyway.

h4kunamata• 30 days ago

Misinformation.

As somebody who spends an insane amount of time inside, the lack for exposure to the Sun mot just affected vitamin D levels but eyes sight too, they were terrible, and also mood.

Taking vitamin D pill instead of Sun is not the same.

joehabeebs2• 29 days ago

I was told I was Vitamin D deficient and accidentally over indexed on supplements and got quite sick. Some of the dosages on OTC are ridiculously high

toxicdevil• 29 days ago

A different personal experience. I had Vit D deficiency. Started on 2000IU per day and was still deficient after months. Then started on 5000IU per day, initially daily but now every other day or so. My last test was in the middle of the "normal" range. I have been taking VitD for 4 years or so. A lot of my symptoms like tiredness, sleepiness etc have improved since then.

I asked my immediate family members to do a test as well. Male/female, young old, across states and even countries. All of them except my mother had low Vit D levels. My mother regularly supplements as its recommended for bone loss prevention in that age.

joehabeebs2• 28 days ago

I was also taking 5K IU per day but had to tone it down after getting quite dizzy. I've been taking them every few days now and have yet to do a follow up but this is helpful to hear!

accidentallfact• 29 days ago

What if rickets is actually a variant of polio, and vitamin D is just a hormone, and not a vitamin?

Rickets still occurs in Africa with abundant sunlight, but with polio still present. (The strains that come from vaccines are usually not counted.)

lonelyrock42• 29 days ago

I have HIV and am under treatment using medication, I have found D3 and K2 helps alleviate some of the side effects of the medication; largely my mood. Which makes a lot of sense because my immunity system is in constant daily activity.

However, I need to get more sunlight; I just don't think supplementation is the same as being in the sun. When I was homeless I never had these mood issues, but that's complicated, living day-to-day & meal-by-meal puts you survival mode so nothing is really past the hour.

All anecdotal, duh.

livingbuddha26• 29 days ago

The veracity of this article depends on who paid you for it, if at all.

dippogriff• 29 days ago

Vice versa, the exaggeration of vitamin D is mildly worthless. Some need supplements, some don't.

deepsun• 29 days ago

I don't understand why literally everyone I know are diagnosed with Vitamin D Deficiency. Even living in sunny California. Wasn't human biology adapted for it in the last 40k years? I understand we spend more time indoors, but literally everyone?

Gareth321• 29 days ago

We evolved to be in the sun for much of the day. We no longer do that. Many of us barely go outside at all anymore. Light skin is an evolutionary adaptation to mitigate the issues related to this in higher latitudes, but it's not match for modern indoor lifestyles.

owenversteeg• 29 days ago

I have made this comment on HN many times [0] now but: it's the goddamn sunlight.

Sunlight has many pathways in the body, and increased vitamin D levels are just one of those pathways. Swallowing one element of a many-element pathway cannot simulate the human synthesis of vitamin D! This should be obvious! Your car might not run because of bad needle bearings, but the solution is not to add them to the gas tank! First, you must always understand.

Sunlight / vitamin D is an especially aggravating issue because we have increasing amounts of research on how sun exposure improves general health. Sleep quality and regularity, mood, cancer incidence (as the article notes), eyesight, skin conditions, overall mortality, virtually every part of human health is improved by going outside. And when I say "improved" I mean improved to such a degree that it would blow 95% of prescribed drugs out of the water. See, for example, the Melanoma in Southern Sweden study where the highest sun exposure cohort had _half_ the all-cause mortality of the lowest group. Unfortunately the Western medical establishment is thoroughly captured by industry and you can't sell a pill that makes you go outside.

[0] https://news.ycombinator.com/item?id=42326209

remix2000• 29 days ago

Here in northern Europe, there just isn't enough sunlight to not become deficient, so a vitamin D supplement is a must.

b-zee• 29 days ago

I looked up data from a calorie tracking app I used a while ago and I got just enough vitamin D. Main sources were fish, eggs and dairy products. However, I ate a lot and I'm quite sure in winter there will have been periods where I didn't get the recommend intake.

So if you live in a northern country and you don't like fish, I suppose it's quite a good idea to take a supplement.

Though as OP said, even if the sun isn't strong enough, there are plenty of benefits to going outside beside vitamin D.

goda902• 29 days ago

Vitamin D is fat soluble, so it would be feasible to build up a supply in summer to last through winter. I've seen it theorized that a cyclical weight gain and loss tied to preindustrial seasonal food availability also plays a role.

Rodmine• 29 days ago

If you gain weight during summer (so that excess vitamin D is stored in fat cells) and use body's stored fat in the winter (eat at a deficit, so that your stored fat, rich in vitamin D, is used), you need no supplementation. This is what all animals living in the region do.

TacticalCoder• 29 days ago

Which could be one of the reason people near the Mediterranean sea (for example in Italy) and tennis players do tend to live longer than average. Now of course there s probably more than one reason but those sure do enjoy time outside.

randusername• 29 days ago

I think science is just too granular to be a reliable input into wellness decision-making. It is too easy for interested parties to enable everyday people to confirmation bias their way into defying common sense.

Of what utility is the truth in decision-making if it is such a narrow truth that it might as well be a falsehood in practice?

Alcoholics talking endlessly about flavonoids, obese people insisting in polyunsaturated fat mayo, sedentary people that don't resistance train drinking soda with protein in it.

rirze• 29 days ago

Unfortunately, sun exposure (specifically UV exposure) is heavily tied to skin cancers and aging. I haven't researched it myself, but my feeling is that, ultimately, there is a calculation where sun exposure / skin risk needs be balanced on your specific genetic makeup.

We really need to drill down into ethnic and racial boundaries to really make sense of how much sun exposure helps us.

Imanari2• 29 days ago

I started to take VitD on a whim and my mood and energy sure improved. Also I feel like I get sick less often. 3 friends whom I recommended VitD told me the same. Living in northern germany. YMMV.

nullbio3• 29 days ago

Placebo is a strong thing. Unless you're actually getting more sunlight, it's doing nothing for you.

Imanari2• 29 days ago

I'll take it ;)

waffle-fry-pan• 29 days ago

tl;dr: The combination of vitamin D/MG cured heart arrythmia and mild depression I suffered from for almost 20 years, so I do not think it is worthless.

I had ventricular extrasystoles for a very long time of my life (18-37). This is a mostly harmless arrytmia that feels like one beat out of the normal rhythm. Around 18, I noticed it for the first time. It came and went, usually I had this for ~3 weeks and then it was gone. Over the years however, I got more and more of those and at the age of 30, I had them ~70% of the year at a rate of 5-6/min. In parallel, I felt stressed and depressed. Not from the fact that I had those, I got used to that over the years, which was not easy.

The doctors I went to said: Harmless, learn to live with it, you will still get very old. Especially the five cardiologists but also the "normal" doctor I saw never took that serious at all. I kept a diary over the years and knew that those could fully go away and I had the feeling that it was somehow correlated with what I eat. Whenever I said that, the response was: "Unlikely, you just don't pay enough attention and do not notice them anymore". Treatment advice was: Live with it or get a catheter ablation done.

Then I then went to a different doctor who actually listened to me when I said they could fully go away. She tested me for vitamin D, B12, magnesium, potassium, iron and a few other things. It turned out that I had a strong vitamin D deficiency (12 ng/ml) and a mild MG/K/B12 deficiency.

Then I took some supplements (a bit of D/MG/K/B each). That helped a bit, but not always and not consistently, but I could definitely tell that there was a relation to taking something or not. I prefer a healthy diet over supplements, so I was not very consistent taking those and when everything was good I simply stopped. The fact that this did help, but not always, kept bugging me though and I wanted to figure out what exactly helped. Long story (~5 years of experimenting) short: It most likely was the combination of D and MG, taking one in isolation did not always improve things. There seems to be a mutual dependency between them, which also seems to be studied to some extend (I started to read med publications at some point, e.g. [0]), but I am a computer scientist and not a doctor so take this with a grain of salt and definitely do not just take stuff without measuring the actual levels first.

Today, I occassionally take supplements (still do not like the idea of taking them on a regular basis) and get my D level tested every once in a while. It is now usually ~30 ng/ml which is still a bit low, but the extrasystoles are fully gone (I am 44 now).

[0] Role of Magnesium in Vitamin D Activation and Function, https://pubmed.ncbi.nlm.nih.gov/29480918/

charlysisto• 29 days ago

Yes magnesium seems to be quit a common deficiency because the heavy use of fertilizer depletes the density of minerals in the food chain. Also magnesium is a very important co-factor in the use of Vit D, so supplementing with a magnesium deficiency might not be of much use. Sadly this seems overlooked in most studies

tigerquoll• 29 days ago

I rather liked his writing style - very easy to follow. He could have a future as a science communicator.

khurs• 29 days ago

I think Vitamin D deficiency hype is driven by supplement sellers.

As someone who grew up in a European country where we don't get long summers, I suffered no demonstrable issues from the lack of sun nor did the many around me.

My family wasn't rich so food was reasonably nutritious but not perfectly balanced either.

Vitamin D supplements are sold widely, including in smaller supermarkets like Lidl and Aldi. And one imagines it all comes out of the same few factories.

There will be some who do need it, but not as many as are led to believe they do.

2000UltraDeluxe• 29 days ago

As many other things, it depends on diet and lifestyle. I also live in the cold north, and generally, if you're fair-skinned, spend enough time in the sun and consume at least some products with natural or added vitamin D, you're usually good.

Having a balanced diet and enough time to spend in the sun isn't a given, though, and many struggle getting enough vitamin D without suppments.

nerbert• 29 days ago

tell that to the 90% of belgians with deficiency

red-iron-pine2• 29 days ago

a years supply of Vit D is like ~$30

you're telling me Big Vitamin is hustling the rubes that much?

the reason it is commonly hyped is because it is in fact reasonably common, and because the fix is cheap and has no real side effects unless you take comically massive doses

AltruisticGapHN• 29 days ago

All I know is I used to have full on colds during winter in my 20s to early 30s, like every winter I would get two weeks of runny nose till the skin became red and irritated, sore and painful throat, coughing, etc. Since I take 25000 IU (D-Cure in Belgium) like 2-3 times a month during winter for the past 15+ years my cold last 2-3 days and symptoms are much more mild. For me the data is there.

epihelix2• 29 days ago

The problem is that you don't know what your situation would be like if you'd not taken Vitamin D. There are too many variables, generally -- e.g. in your early 20s and 30s you're likely socialising with many more people (so, more exposure chances), and you may also have young children (even worse disease vectors).

I'm similar to you in experience, btw, except that I don't believe correlation is causation. But as it won't do any harm, most of us don't regularly monitor our Vitamin D levels, and Vitamin D supplements are cheap -- it becomes a harmless form of Pascal's wager that I'm happy to keep making. Nothing to lose except a very, very tiny amount of money.

fearnot• 29 days ago

Again, dynomight proves he's better than us.

bcjdjsndon• 29 days ago

and it will still tell your bones to scavenge calcium... So the body scavenges a lot of calcium from your bones...

Bones take calcium from bones? Net effect 0 then?

adrian_b5• 29 days ago

Obviously that was an incorrect phrasing.

The concentration of calcium ions in the extracellular water and in blood is always kept approximately constant.

The bones are a reservoir of calcium in solid form, so whenever the concentration of calcium ions in the extracellular water drops the bones release calcium ions and whenever that concentration increases the bones retain calcium ions.

This takes care of short term fluctuations. In order to also keep the amount of calcium stored in the bones approximately constant, the gut will try to absorb more calcium from the food when it is insufficient and the kidneys will excrete the excess, when it is too much.

voxleone• 29 days ago

Quod abundat non nocet

economistbob2• 29 days ago

Thousands of words and no references list. Lame. Makes me suspect a piece written a bot. I have to dismiss almost all of it since there is no way to fact check and the article is filled with those asides that the bots put in there. The asides I refer to are the "are you still with me" and other psuedo-in-your-face punchy nonsense. Half the articles on the internet think I want backfill and history and punchy check-ins rather than the direct information that I used to scan through and obtain in about twenty seconds, but somehow those brand new AI slop sites are the top results on all engines (corruption since they sell services to generate those pages).

Lame. It started like enjoying an encyclopedia and ended like getting my face punched by a narcissistic robot who might have lied about facts and gave no way to spot check except redoing the entire article again myself from scratch. A novella on biophysics and no works cited?

Reading 7k words on biophysics with supposed data and science facts and getting hit with dozens of self reference footnotes instead of external citations is offensive to my intelligence.

I do not have the karma for the downvote button so I shall simply leave this.

Vitamin D is rat poison. The stuff they use in randomly controlled trials is not the stuff your body makes on its own. Too much sun and skin produced vitamin will not kill you. Too much rat poison will.

Real human research per the Material Safety Data Sheets with zero slop:

https://chemtrails.substack.com/p/vitamin-d-is-rat-poison-th...

egberts1• 29 days ago

methylcobalamin B-12 plus Vitamin D3 is the preferred form.

Skip the D2 vitamin.

rizsyed1• 29 days ago

I think taking a supplement every day is a good idea. I used to suffer from low vitamin D levels constantly until I started taking a daily vitamin D tablet.

ck2• 29 days ago

the Vitamin D RDA is too low at 800iu

but taking more than 2000iu per day is not just pointless but dangerous without blood testing

Vitamin D won't cure anything once there is a disease or illness

but it does show some preventative benefits

whole lotta people on Reddit do have blood tests showing it's way too low but those of course are the loudest voices

nullbio3• 29 days ago

Vitamin D is a biomarker of a process that happens in the body that is beneficial for longevity. This biomarker is created in response to receiving sunlight. The synthetic vitamin itself, does little, if anything, for your health. The process of receiving the sunlight is what benefits your health. This applies to a lot of other vitamin supplements as well.

So whilst you may be able to take a supplement to boost your vitamin D levels, the negative health effects of lack of sunlight are still going to occur.

redrove• 29 days ago

Do you have any sources for this? Genuinely interested in reading more.

xolox2• 29 days ago

I've recently run into and explored research explaining that natural sunlight stimulates energy production in mitochondria, resulting in an energizing and healing effect completely separate from vitamin D production.

I feel bad for posting this without references so here's one reference I could find right now:

This study shows that longer wavelengths in sunlight are transmitted through the body. When these are presented via NIR LEDs in a laboratory-controlled environment at much lower energies, they again have the ability to be transmitted through the body and also are associated with improved visual function independent of ocular exposure. Hence, body penetration by longer wavelengths impacts systemically. Longer wavelengths improve mitochondrial membrane potential and ATP production and improve function in a species conserved pattern that can impact on mobility, visual function and cognition, particularly in ageing. In short lived animals they can extend average life span.
Taken together, these data provide evidence of the importance of the full spectrum of sunlight for human health. They also highlight the potential dangers of the restricted spectra found in white LED lighting in the modern built environment that lacks longer wavelengths and whose output is generally restricted to around 400–650 nm. The absence of longer wavelengths from LED light sources may have implications for public health that should be addressed.

Source: https://www.nature.com/articles/s41598-025-09785-3#Sec5

trevorkoob2• 28 days ago

One interesting aspect of Vitamin D that is not regularly discussed is the photo-isomerization of Vitamin D into inactive isomers in the skin.

I think of it similarly to Beta-Carotene, in that consuming the "natural source" has no known toxic amount, while consuming processed vitamin A can be toxic in large doses.

Increasing sun exposure will not raise blood vitamin D metabolite concentration indefinitely, and we don't have good studies that accurately measure the amounts of Vitamin D and its photo-isomers and their concentration in relation to large doses of UV exposure.

Therefore, through sun exposure, people may be storing large doses of Vitamin D isomers in their skin, keeping their levels much higher than typically prescribed oral supplementation levels.

euroderf• 29 days ago

Early into the Covid pandemic, there was talk that vitamin D had some protective effect. Did this ever pan out into any kind of recommendation supported by evidence ?

stevedt• 29 days ago

https://pmc.ncbi.nlm.nih.gov/articles/PMC8541492/

bingoMen• 28 days ago

This is a very good, understandable article.

The worthlessness of Vitamin D is mildly exaggerated

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