101–110 of 218 posts
It seems interesting that Vitamin D may be so much more prone to false correlations due to the fact that it's tied to going out in the sun, and going out in the sun is what healthy people do. Since so many illnesses and conditions, from psychological to physical, can keep you indoors, one could conclude that vitamin D is really a miracle pill. I take 1k iu a day, since I barely go outside anymore, but I'd probably cu…
Why do you barely go outside?
For other reasons I get tested for vitamin D every few months and managed to get my levels just above the normally recommended amount as per doctors advice. When people are saying they’re taking 25-100k UI a day I’m just stumped why they’d be doing that without medical advice, the amount to change my levels was nothing in comparison.
It seems interesting that Vitamin D may be so much more prone to false correlations due to the fact that it's tied to going out in the sun, and going out in the sun is what healthy people do. Since so many illnesses and conditions, from psychological to physical, can keep you indoors, one could conclude that vitamin D is really a miracle pill. I take 1k iu a day, since I barely go outside anymore, but I'd probably cu…
However most often than not, surrogate markers are enough. Also RCTs tend to coroborate the findings from observational studies in about 70% of the cases. Also for really hot topics, like diabetes management, we do have year-long RCTs too.
And drawing conclusions from systematic reviews and meta analyses of RCTs, well, that's basically the best we can do.
For assessing the strength of available evidence, I recommend reading the following: https://examine.news/how-to-read-a-study
So Vitamin D deficiency is linked to cancer, heart disease, respiratory infection, stroke, diabetes, and death. But taking it as a supplement helps with none of the above. What is a reasonable hypothesis then? That having an active lifestyle that brings you outside in the sun both causes your Vitamin D to go up, and is correlated with better physical health in general?
I would frame it in the opposite direction: having a serious illness is correlated with low levels of Vitamin D. People with a serious illness may stay inside more, and go outside less. It's possible that "low levels" of Vitamin D are still within the healthy range, and they merely are an indication of how much time the person has spent outside during the day. In other words, it's possible that Vitamin D is pure symp…
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Very hard to quantify sun exposure and do this in a controlled way.
Very hard? Sounds one of the easiest things to measure and control for... Tack a sensor (e.g. watch like) to people working outside, vs people working inside, inmates, etc for example... Check people in long norther nights vs the carribean (you can find lots of people of either place in the other).
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There is a lot of excitement about this study, but the details in it matter. It was randomized - but when you look at the two groups (treatment vs. control), they had some key differences. The control group (who didn't receive Vitamin D) had more men (69% vs 54%), more people with hypertension (57% vs 24%) and diabetes (19% vs 6%). So the groups were not the same. If you just compare the numbers of those who went int…
Interesting! Can you quote the part of the study where they say the results are not statistically signifcant when you control for diabetes and hypertension?
> Randomization generated groups with comparable percentage of unfavorable risk factors as there was no significant difference in subjects with at least one risk factor, except for high blood pressure and diabetes mellitus, known risk factors for unfavorable disease progression, which were more frequent in patients not treated with calcifediol.
> However, even considering these factors, calcifediol significantly decreased the need for ICU admission in COVID-19 patients in a way not previously reported in this process until now.
Earlier quoted context omitted.
There is a lot of excitement about this study, but the details in it matter. It was randomized - but when you look at the two groups (treatment vs. control), they had some key differences. The control group (who didn't receive Vitamin D) had more men (69% vs 54%), more people with hypertension (57% vs 24%) and diabetes (19% vs 6%). So the groups were not the same. If you just compare the numbers of those who went int…
Interesting! Can you quote the part of the study where they say the results are not statistically signifcant when you control for diabetes and hypertension?
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> It's not even necessarily the case that going outside is healthy, but that healthy people tend to go outside more. This is a departure from the discussion of supplementing vitamin D though, isn't it? I guess the treatment "go out and do sports" is a very different one compared to "X amount of vitamin D per day as a supplement" and the former may indeed be healthy , while the latter may not be, even though they both…
> This is a departure from the discussion of supplementing vitamin D though, isn't it? I don't think so, no. If my hypothesis is correct, the problem is not that they didn't go outside and play sports. The problem is that they are sick , and sick people don't go outside as much. Forget Vitamin D for a moment. Imagine that every time you were outside for an hour, the Outside Fairy granted you one Outside Token. Over t…
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Interesting! Can you quote the part of the study where they say the results are not statistically signifcant when you control for diabetes and hypertension?
I’d also like specifics about the “not statistically significant” part - because otherwise there can be a suspicion of cherry-picking the available data. Which I felt, reading parts 2 and 3 of these blog posts, was definitely a possibility.
Earlier quoted context omitted.
There is a lot of excitement about this study, but the details in it matter. It was randomized - but when you look at the two groups (treatment vs. control), they had some key differences. The control group (who didn't receive Vitamin D) had more men (69% vs 54%), more people with hypertension (57% vs 24%) and diabetes (19% vs 6%). So the groups were not the same. If you just compare the numbers of those who went int…
Interesting! Can you quote the part of the study where they say the results are not statistically signifcant when you control for diabetes and hypertension?