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Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

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Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#41

Post by fridder »

tchalla wrote: post #39
niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

> This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels Generally, when a study is done in the US - no one will ever question the location. The moment the study is outside the US, "not US so not generalisable" questions always arise.

to be fair, the US has a lot more variability in climate and population than most countries

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#42

Post by bootsmann »

p-o wrote: post #34

I don't know, the study seems pretty mild in findings and the research doesn't mention anything about the socioeconomic environment in which each of the children grew in. Maybe it's the high dose vitamin, maybe it's because one cohort was skewed one way on the socioeconomic spectrum, maybe it's something else entirely. More evidence would be needed imo to confirm Vitamin D3 has a direct contributor to cognitive perfo…

> the research doesn't mention anything about the socioeconomic environment in which each of the children grew in.

The main trick behind randomized control trials is that you can disregard factors like this because these effects would be randomly distributed as well.

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#43

Post by nine_k »

kloop wrote: post #28
niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

Do they need more vitamin D? I thought they just needed more sun to get the same vitamin D

Apparently the pale, semi-translucent skin is a mutation that allowed hominids to live at high latitudes, where darker-skinned hominids would whither due to the lack of vitamins of the D group [1].

That same mutation made them vulnerable to the levels of sunlight at lower latitudes, susceptible to sunburns, etc.

[1]: https://pmc.ncbi.nlm.nih.gov/articles/PMC8359960/

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#44

Post by darth_avocado »

tchalla wrote: post #39
niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

> This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels Generally, when a study is done in the US - no one will ever question the location. The moment the study is outside the US, "not US so not generalisable" questions always arise.

> when a study is done in the US - no one will ever question the location

Studies everywhere are now being scrutinized for the participant cohorts because it is now widely recognized that biological differences exist between different groups. Some medications for example aren’t sufficiently studied for effects on women vs men and are being reviewed.

Plus, studies in US are less scrutinized because researchers are aware of the need for a diverse cohort and you are more likely to get one in the US vs elsewhere.

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#46

Post by cientifico »

niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

Correction in 2. Contrary to popular believe, sunnier countries in Europe have higher deficiency in vitamin d.

Spain have lower levels of vitamin d than Denmark.

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#47

Post by filoleg »

tchalla wrote: post #39
niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

> This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels Generally, when a study is done in the US - no one will ever question the location. The moment the study is outside the US, "not US so not generalisable" questions always arise.

The grandparent explained exactly why it is an issue though. It isn't because US is somehow just magically more legitimate than Denmark.

As they stated, it is because the population of Denmark is very homogenous, as opposed to the US. If you are trying to make a generalization that applies to a range beyond just white people, having Denmark as your sole sample is clearly flawed.

Along the same lines, picking Japan for the purpose of generalizing to wider racial/ethnic groups would also be a bad idea. Not because their research is untrusted/considered non-reputable (it is quite the exact opposite), but because their population is too homogenous.

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#48

Post by appplication »

tarkin2 wrote: post #24

I'm perhaps missing something but if there were a significant connection, wouldn't this mean those in sunnier climates would have better verbal and visual memory? If there were a connection then I would wager that there are more significant factors, since I have seen or heard of no evidence to assume those in sunnier climates have better verbal and visual memory. The results of this study seem to show no significant…

Not necessarily, if the effect was due to exposure to levels beyond what you’d even get in sunnier climates. It also could be possible those in sunnier climates do experience this effect and it was unnoticed, due to political and socioeconomic issues associated with typical equatorial countries

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#49

Post by doikor »

cientifico wrote: post #46
niteshpant wrote: post #23

I have thoughts on this 1. Yes, vitamin D actually controls a lot of bodily functions it’s very easily set aside as not a “main” factor when in reality it actually controls a lot 2. This study was done on women in Denmark only which isn’t a great study subject considering Denmark doesn’t get a lot of sun to begin with so most of these women would already start at very low levels 3. This doesn’t directly correlate to…

Correction in 2. Contrary to popular believe, sunnier countries in Europe have higher deficiency in vitamin d. Spain have lower levels of vitamin d than Denmark.

The countries in the northern parts of Europe know this is an issue and thus fortify some commonly consumed food items (milk) with vitamin d.

In places like Spain only some “premium” milk gets this treatment.

Re: Vitamin D3 During Pregnancy and Cognitive Performance at 10 Years

#50

Post by p-o »

bootsmann wrote: post #42
p-o wrote: post #34

I don't know, the study seems pretty mild in findings and the research doesn't mention anything about the socioeconomic environment in which each of the children grew in. Maybe it's the high dose vitamin, maybe it's because one cohort was skewed one way on the socioeconomic spectrum, maybe it's something else entirely. More evidence would be needed imo to confirm Vitamin D3 has a direct contributor to cognitive perfo…

> the research doesn't mention anything about the socioeconomic environment in which each of the children grew in. The main trick behind randomized control trials is that you can disregard factors like this because these effects would be randomly distributed as well.

Not always, and in this case, the study is very light on details on how the selection process was done. The burden of the RCT is on the research team and the quality of the randomization varies between studies.

If a study is going to draw debatable conclusion after 10 years on high dose Vitamin D during pregnancy, I'd expect at least some comment in the study on the general socio economic landscape and grouping.

Regardless, this study looks like a sham to me.

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