Reduced cancer mortality with daily Vitamin D intake
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Re: Reduced cancer mortality with daily Vitamin D intake
#2"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen."
This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a preregistration, if this was registered as a secondary resuld and if they had done a proper statistica analysis of multiple outocmes.
Re: Reduced cancer mortality with daily Vitamin D intake
#3I've been taking a daily vitamin D supplement since COVID-19 broke out in the USA. I believe there's a lot of evidence that many people are deficient in vitamin D. I don't know if supplements are the best way to attack that but it's one of the easiest ways. Getting daily sun exposure isn't always convenient and not really possible for a good chunk of the year since we have real winter here.
Re: Reduced cancer mortality with daily Vitamin D intake
#4"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen." This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a prereg…
That's what's confusing me: 105,000 participants in a study should have resulted in thousands of cancer deaths, a 12% drop should be pretty noticeable even with 10% of the data.
Re: Reduced cancer mortality with daily Vitamin D intake
#5"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen." This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a prereg…
Re: Reduced cancer mortality with daily Vitamin D intake
#6"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen." This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a prereg…
Yeah, in addition to the XKCD comic it also reminds me of "Spurious Correlations" lol https://tylervigen.com/spurious-correlations
Re: Reduced cancer mortality with daily Vitamin D intake
#7"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen." This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a prereg…
That's what's confusing me: 105,000 participants in a study should have resulted in thousands of cancer deaths, a 12% drop should be pretty noticeable even with 10% of the data.
How exactly are you getting "should have resulted in thousands of cancer deaths"?
A population of 100,000 should expect to see 144.1 deaths[1].
If you evenly divide the study group into two 52,500-sized groups(treatment + control), each group should expect to see 72 deaths. A 12% drop in one of the groups is 8.6 deaths. As a colleague would say, that's very few clams from which to make a chowder.
Perhaps the researchers are using more advanced tools than I am, but even assuming a 12% difference between treatment and control does not result in a chi-squared test with any reasonable significance. ie: the null-hypothesis(there is no difference between groups) cannot be rejected.
1. https://www.cdc.gov/cancer/dcpc/research/update-on-cancer-de...
Re: Reduced cancer mortality with daily Vitamin D intake
#8In that circumstance, I've heard that vitamins and supplements can be tricky; the additional nutrition may feed the cancer, before it feeds you. Just one more factor to consider.
Re: Reduced cancer mortality with daily Vitamin D intake
#9> However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen. In the four studies with the infrequent hogher doses, there was no effect on cancer mortality. In contrast, in the summary of the ten studies with daily dosing, the researchers determined a statistically significant twelve percent reduction in cancer mortality.
What exactly is the recommendation here, low or higher doses? or something else because Im struggling to understand this
Re: Reduced cancer mortality with daily Vitamin D intake
#10"When all 14 studies were pooled, no statistically significant results emerged. However, when the studies were divided according to whether vitamin D3 was taken daily in a low dose* or in higher doses administered at longer intervals*, a large difference was seen." This sounds fishy. Sounds like their primary result was nothing, and then they looked for something else. Would require some checking if they had a prereg…
D3 (animal-based) > D2 (plant-based) > D1 (synthetic), at least in humans if you read the literature, that is.
The fishy thing is how actual scientists do whole studies using only D1 and then draw conclusions.