Vit D supplementation and major cardiovascular events: D-Health randomised trial
bmj.com
bmj.com
This is standard reporting but you need to know biostats to appreciate what it's saying because that's who articles are written for.
ok, nothing to see here...
Low blood levels of Vitamin D is highly correlated with just about every disease known to mankind.
Yet, studies repeatedly have shown that Vitamin D supplementation has next to no benefit in curing those diseases.
So either there's a jointly correlated third factor like sun exposure or low Vitamin D levels are CAUSED by those diseases and in general just an indicator of overall poor health.
Source?
Every article/discussion that shows up here suggests the jury is still out in this as well.
- High incidence of MS in northern hemisphere compared to low incidence near the equator. http://www.bandolier.org.uk/booth/neurol/MSgeog.html
- Better outcome for skin cancer patients if diagnosed going into summer vs winter. https://onlinelibrary.wiley.com/doi/abs/10.1111/dth.13625
There's a decent article on the subject on nih.gov here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2290997/
And another by Harvard here: https://www.health.harvard.edu/diseases-and-conditions/benef...
The reduction in mortality remains after controlling for level of exercise. Also, using sunbeds and sunbathing while on holiday is associated with reduced mortality, at least in this large study in Sweden:
Vitamin D 100% cures a vitamin D deficiency. And Vitamin D deficiency 100% causes disease.
This study was only looking at how vitamin D supplementation affected a large swath of people, both those deficiency and those replete. So why is everyone surprised the results ar inconclusive?
As an aside, starting Vitamin K2 a few months ago has given me a noticeable increase in energy and focus, make of that what you will. Vitamin K2 is one of those somewhat hard to get vitamins in a typical American diet.
In case anyone isn't sure about kimchi and natto every few days, but "for better cognitive ability" would be a nice excuse usable for occasional sushi rolls, stir-fries, just a bit of extra Parmesan, maybe even fries :p
Why not just take a multi vitamin and think not much of it.
Probably everyone is low on vitamin D atleast at some point in the year and it costs next to nothing to just have a few other vitamins along for the ride.
These doses are kind of laughable compared to what you get from the sun:
>A minimum erythema dose (1 MED) amounts to about 30 minutes midsummer midday sun exposure in Oslo (=20 mJ/cm2). Such an exposure given to the whole skin surface is equivalent to taking between 10,000 and 20,000 IU vitamin D orally, i.e. as much as 250-500 μg vitamin D
https://pubmed.ncbi.nlm.nih.gov/19667143/
Sure, you might not have your entire skin exposed, but I'm the past we didn't only get 30 minutes of sun exposure either. It might just be that they didn't see any significant effect because the vitamin D supplementation wasn't high enough.
Multivitamins probably aren't going to give you enough either. Maybe if you take take them with 8g of fat and no caffeine, but even then it would depend on the multivitamin.
With 4000ui per day being the safe limit for someone who's not monitoring levels. (Too much vitamin D is pretty grim because of the effects on calcium levels).
Once you get into checking levels you lose all benefits of a simple intervention.
That's because an error was made when the RDAs were initially assessed. 400 IU is going to have no effect. I believe in the above link if the sunlight study they even mention that interventions below 1500 IU/day have no effect.
>Too much vitamin D is pretty grim because of the effects on calcium levels
Sure, but I wonder about this 4000 IU limit. Experts also royally screwed up last time with their suggestions that have had an impact for years . This was such a monumental screw up that somehow took decades to address:
>A statistical error in the estimation of the Recommended Dietary Allowance (RDA) for Vitamin-D was recently discovered, indicating that 8895 IU/day are needed for 97.5% of individuals to achieve values ??50 nmol/l, analyzing correctly the same data used by the Institute of Medicine. [0]
>Since all-disease mortality is reduced to 1.0 with serum vitamin D levels ≥100 nmol/L, we call public health authorities to consider designating as the RDA at least three-fourths of the levels proposed by the Endocrine Society Expert Committee as safe upper tolerable daily intake doses. This could lead to a recommendation of 1000 IU for children <1 year on enriched formula and 1500 IU for breastfed children older than 6 months, 3000 IU for children >1 year of age, and around 8000 IU for young adults and thereafter. [0]
That being said, I'm unsure if I would supplement 8000 IU either, but 2000 a day for a study still seems low.
Apparently it's not that easy to get vitamin D toxicity:
>A total of 127,932 serum/plasma 25(OH)D measurements were performed on 73,779 unique patients. Of these patients, 780 (1.05%) had results that exceeded 80 ng per mL and 89 patients (0.12%) had results that exceeded 120 ng per mL. Only 4 patients showed symptoms of vitamin D toxicity. Three of these cases involved inadvertent misdosing of liquid formulations. [1]
Although, it's important to keep in mind that others could've had problems, but just not shown identifiable symptoms.
[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/
[1] https://academic.oup.com/labmed/article/49/2/123/4807321
From nutritionfacts.org: "How Do Turmeric and Black Pepper Work Together?" [1]
[0] https://www.amazon.com/gp/product/B019U8KR4G
[1] https://nutritionfacts.org/blog/why-pepper-boosts-turmeric-b...
As mentioned above, it's not abundant in the western diet. I wonder if places where there is more K2 in the diet have less osteoporosis?
Medicine is moving to become more personal and preventive rather than purely guess and scientific method driven, especially with the advancement of AI and modern medicine.
When I read this trial, I see good news for those who personally believe in Vitamin D and have experienced benefits from it. I see no news for those who do not care for Vitamin D and have not tried it.
This is an incremental study that helps push Vitamin D forward in my opinion, even if the findings are weak.
For me 4k IU a day seems to be the perfect dosage
How did you come to this conclusion?
To the best of my knowledge, all actual trials that tested the hypothesis got a null result, just like this study.
Ultimately while it would be interesting to know if CVD risk is reduced with vitamin D supplementation in those who are vitamin D deficient, it is largely an academic question as those individuals should be taking vitamin D supplements anyway.
https://wiki.cancer.org.au/skincancerstats/UV_radiation#:~:t....
https://www.ga.gov.au/scientific-topics/energy/resources/oth....
So yeah vitamin d might help on one hand, but cause it’s own issues in different areas.
No more vitamins for me. Better to eat well and get the occasional bit of Sun.
Sometimes I think they do these studies to discredit the value of nutrition and health.
I think the study is valuable in that it suggests blindly giving everyone vitamin D is not strongly correlated with reduced cardiovascular events. I often see it stated that "nearly everyone" in developed countries is vitamin D deficient and so the majority of us should be supplementing.
I think results like this make for a strong argument that it's more important to get your individual levels checked before you waste your money on supplements.
One thing that's really important to note here is that the participants are all based in Australia. That's pretty significant considering the amount of sun Australians are exposed to. By some measures, Australia is the "sunniest" place in the world. And since exposure to sun causes your body to produce vitamin D, it's likely Australians have naturally higher levels than most other populations.
Since it’s not possible to do this should we give up studying these sorts of things? Scientists study theses types of things the best way they know how. They search for clues, evidence. Then more studies are done. Eventually, hopefully, enough evidence has been amassed to make a conclusion that has a very good chance of being correct. It’s not perfect but it’s much better than doing nothing.
The authors acknowledge the limitations of the conclusions that can be made. They write:
Vitamin D supplementation might reduce the incidence of major cardiovascular events, although the absolute risk difference was small and the confidence interval was consistent with a null finding. These findings could prompt further evaluation of the role of vitamin D supplementation, particularly in people taking drugs for prevention or treatment of cardiovascular disease.
No. And no one said that. But we should outline and document the problems studies like this may have. That's how science works.
Of course vitamin D is going to help some people more than others based on their genetic heritage. I am one of these people, and I get most of my vitamin D needs from my diet, mainly fish. Sun exposure might not be the best route for people to get their vitamin D, and this is especially true for light skinned northern people.
I ignore these genetically diverse nutritional studies and just focus on the metabolic pathways and my own genetics.
I have not tried getting it exclusively from fish, but you're getting other benefits there as well.
So, null result?
Just because it had an insignificant result for a genetically random population does not mean it did not help any individual in the study.
This is true.
-that any effect measured is likely due to chance alone.
But this is a stronger statement that is not.
The 95% confidence interval for the hazard ratio was 0.81 to 1.01 which means there is more than a 5% probability that the result was due to chance, but not that it's likely due to chance, which implies "more probable than not". The result is more like: if the measured effect is real, it's small enough that a significantly larger study would be needed to demonstrate it with sufficient confidence.
That's a true statement, but it's also not known whether there are any such people.
And it's bigger than that. It's one of the few large and well controlled studies done on the subject. It invalidates most of what was known about it (even though AFAIK, it doesn't contradict them).
Looked at another way, imagine the authors used a 94% confidence interval instead of 95%. Suddenly, the risk reduction from vitamin D becomes “statistically significant”. There is nothing magical about 95%, and use of p values to assess boolean effective/ineffective should have been done away with a long time ago.
Related:
The Earth is Round (p < 0.05) [1994]: https://www.sjsu.edu/faculty/gerstman/misc/Cohen1994.pdf
Sadly, the Earth is Still Round (p < 0.05) [2012]: https://cmapspublic2.ihmc.us/rid=1P501PBWQ-1S6L809-28MX/Zhu_...
A study on the effect of Vitamin D on repiratory diseases would make much more sense.
Many Vitamin D studies like this one talk about major events (i.e. things associated with sudden death), less so about the symptoms of cardiovascular health.
Other studies talking about cancer will say similar that higher Vitamin D is found in certain cancers or the opposite effect in other cancers.
Definition of a controversial topic.
You could give vitamin D to all those 100 people and vitamin D would appear to do nothing. Unless of course she one of the two people that it did work for.
So can you see how these randomized controlled trials of nutritional supplementation’s are useless for any individual?
I don’t care how vitamin D affect a population, I care how it affects me.
What I think would be interesting is looking at something like "time spent outside" to see whether Vitamin-D might be more significant on persons with too little sunlight exposure (physical activity would be an obvious confounder you have to control for).
Ultimately the study wasn't especially meaningful and weak effects aren't too surprising as a result.
Cold water fish has the highest amount of vitamin D.
The fact that the skin of your ancestors rapidly evolved to become much lighter as they migrated to more polar latitudes tells you all you need to know about whether diet was an adequate source of vitamin D.
Light-skinned people are particularly well-suited to obtaining all the vitamin D they need from sunlight alone.
It is dark-skinned people currently living far from the equator who benefit the most from vitamin D supplementation, because the melanin in their skin reduces their ability to synthesize vitamin D from the meager amount of sunlight they get.
The people who lived in Western Europe for likely longer that it took for white skin to evolve in the middle east/caucasus(?) region were much darker skinned.
Also given how long anatomically modern humans have existed several thousands years is not such a short period.
The problem isn't that you won't get enough sunlight if you lay down naked in the sun, the problem is that you can't because it is too cold.
All the northernmost US states have a period of insufficient sunlight/angle to produce Vitamin D, and basically all of Canada is north of that.
Maybe there's an island that is Canadian territory that is south of say New York or San Francisco that I don't know about of course.
Above/Below a certain latitude (N/S) there is a window of time where the sun never hits that angle at any point during the day, so you could sit outside naked all day long and still get zero vitamin D.
If this seems counterintuitive consider if you keep going far enough away from the equator and get into the arctic/antarctic the winter has no sunlight at all, and you clearly can't produce Vitamin D from sunlight if the sun never rises.
My city in Canada about 46.2 degrees north and about 300km from the eastern Maine border. Here in winter it gets light at 8am and dark at 4pm if there are no clouds. So most people are at work they go to work in the dark and leave when it is dark.
The purpose of a study like this would be to determine whether vitamin D supplementation is indicated for CVD prevention independent of vitamin D deficiency, which is why the study recruited from the general population, excluding only those in whom vitamin D supplementation would be contraindicated.
Amount produced is dependent on both duration and intensity.