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Vitamin D supplementation to prevent acute respiratory tract infections (2017)

bmj.com

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Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#151

Post by gameswithgo »

Marsymars wrote: post #116
Gravityloss wrote: post #24

Earlier quoted context omitted.

Mind boggling that this kind of a thing isn't known. This says the total economic effect of seasonal influenza in the US alone is 87 billion per year. That's six NASA:s worth: https://www.sciencedirect.com/science/article/pii/S0264410X0...

> Mind boggling that this kind of a thing isn't known. I was blown away recently when I discovered that the causes of myopia aren't really known, but don't seem to be primarily genetic.

some evidence that being indoors too much when young could contribute.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#152

Post by therealcamino »

kaztal wrote: post #76
thinkingemote wrote: post #42

Earlier quoted context omitted.

Its not possible to get any vitamin D from the sun in the winter in these high latitudes even if you outside in the sun all day with short sleeves. The angle of the sun is too low. We are just beginning march now, so the sun should soon be beginning to be high enough to give some benefit.

Sweden here. My partner is a doctor, she claims with assurance that you can't make a carpet decision like this. People who come from norther latitudes are used to the lack of sun, and their bodies don't need more vitamin D than is provided. Depending on your heritage, ymvm.

I love the phrase "carpet decision". Although we don't have it in English, I'm guessing it's roughly equivalent to "blanket statement", something that applies in all cases without exception?

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#153

Post by stjohnswarts »

brokensegue wrote: post #139
_cairn wrote: post #136

I had my Vitamin D levels tested last year, was enlightening. For those interested it's a pretty painless (small blood sample) and inexpensive test.

I was recently charged several hundred for a vit D test. The price is basically random in the US.

That's insane, my whole panel for vitamin d, some other vitamins, insulin levels, immune analysis, etc all are about $120 when I do my annual checkup.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#154

Post by stjohnswarts »

hannob wrote: post #54

Please note that this is a bit older (2017). As I personally have a cold quite often I was curious to look into this a bit. Around the same time another metaanalysis was published with a similar question [1], but quite different results (i.e. Vitamin D is unlikely to help). Here's [2] an (unfortunately only german) article by an austrian webpage associated with the cochrane collaboration (i.e. that should be consider…

You don't need vit D if your blood levels are not low, but vitamin d supplements absolutely can raise it if it is low, there is not arguing with that fact. It's established science.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#155

Post by bdcs »

alexpotato wrote: post #109
BurningFrog wrote: post #88

Earlier quoted context omitted.

This is one reason arctic people eat so much (vitamin D rich) fish. The other is of course that a plant based diet is impractical when plants are only alive half the year. White skin itself is an evolutionary adaption for getting enough vitamin D outside of tropical Africa. The extreme "melanin-anemic" blond & blue eyes look of Scandinavia is thought to be because it has a uniquely warm weather for the latitude, whic…

I don't have the source handy but there was a geographic point made about Scandinavia that went something like this: - Scandinavia is very far north and therefore gets less sun in the winter (obviously) - Apparently the soil of Scandinavia is well suited to crops that are high in Vitamin D The soil being good for Vitamin D crops (plus lightening of skin/hair and fish diets etc) was a part of why people were able to l…

> - Apparently the soil of Scandinavia is well suited to crops that are high in Vitamin D

IIUC it's the other way around. soil/climate allows for foods low in Vitamin D -> Vitamin D needed from other sources -> evolutionary pressure for getting it from the sun -> less melanin in skin

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#156

Post by agumonkey »

kasperni wrote: post #142
dharma1 wrote: post #111

Earlier quoted context omitted.

how high is high dose for you?

4,000 IU 4-5 days a week. I did a loading phase with a bit more.

so the program is > 4000 at first then stabilize around 4000 ?

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#157

Post by logfromblammo »

davidw wrote: post #130
leto_ii wrote: post #21

I can say from my own experience that the lack of vitamin D can have a significant impact on both mind and body. I suspect that essentially all people living at relatively northern latitudes have some sort of vitamin D deficiency. From what I know you need to have your face and arms exposed to direct sunshine for at least 15 minutes/day to keep healthy vitamin D levels in the body. Good luck with that in the European…

> your face and arms exposed to direct sunshine for at least 15 minutes/day I wonder what the actual numbers are for this. This weekend, I got out for a couple of 3 hour bike rides, for instance, but it was chilly out, so nothing but my face was exposed.

The reaction is as follows:

7-dehydrocholesterol --(UVB @ 296nm)--> previtamin-D --(thermal isomerization)--> cholecalciferol

The first step reaches equilibrium after about 15 minutes in Fitzpatrick type 1 skin in UV index 3-5 (moderate), and about 2 hours in Fitzpatrick type 6. The total amount produced is dependent on the surface area of exposed skin, and the previtamin isomerizes slowly, over about 12 days.

Time to equilibrium is about half the time to acquire sunburn at a UV index high enough to catalyze the previtamin-D reaction. At UV index 6-7 (high), time to burn is about the same as the time to reach previtamin-D equilibrium. At UV index 8 or higher (very high), you will burn faster than you make previtamin-D, and should maybe avoid being exposed during the midday hours. At UV index 11 or higher (extreme), if you are Fitzpatrick type 1, you will carbonize to a burnt matchstick the instant you step out of shadow, like a cartoon vampire, and you should not only not be outside, but should also be huddling in a dark basement waiting on the tyranny of the sun to pass.

Thanks to the equilibrium in the skin, the maximum absorbed dose from sunlight is the equivalent of about 20000 IU per day. High vitamin-D intake also requires increased vitamin-K consumption to reduce calcification of soft tissues.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#158

Post by BurningFrog »

alexpotato wrote: post #109
BurningFrog wrote: post #88

Earlier quoted context omitted.

This is one reason arctic people eat so much (vitamin D rich) fish. The other is of course that a plant based diet is impractical when plants are only alive half the year. White skin itself is an evolutionary adaption for getting enough vitamin D outside of tropical Africa. The extreme "melanin-anemic" blond & blue eyes look of Scandinavia is thought to be because it has a uniquely warm weather for the latitude, whic…

I don't have the source handy but there was a geographic point made about Scandinavia that went something like this: - Scandinavia is very far north and therefore gets less sun in the winter (obviously) - Apparently the soil of Scandinavia is well suited to crops that are high in Vitamin D The soil being good for Vitamin D crops (plus lightening of skin/hair and fish diets etc) was a part of why people were able to l…

I can't find any crops that are high in vitamin D.

Some fungi have decent vitamin D, but it's certainly not a major "crop" in Scandinavia.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#159

Post by all_blue_chucks »

leto_ii wrote: post #21

I can say from my own experience that the lack of vitamin D can have a significant impact on both mind and body. I suspect that essentially all people living at relatively northern latitudes have some sort of vitamin D deficiency. From what I know you need to have your face and arms exposed to direct sunshine for at least 15 minutes/day to keep healthy vitamin D levels in the body. Good luck with that in the European…

One's person experience is not meaningful for a population.

Re: Vitamin D supplementation to prevent acute respiratory tract infections (2017)

#160

Post by kasperni »

agumonkey wrote: post #156
kasperni wrote: post #142

Earlier quoted context omitted.

4,000 IU 4-5 days a week. I did a loading phase with a bit more.

so the program is > 4000 at first then stabilize around 4000 ?

Yes, I didn't start until late December so I did a little loading with a bigger dose [1]. Next time I'm just going to start around October instead of running into a deficiency.

[1] http://gmmmg.nhs.uk/docs/nts/NTS-Recommendation-on-Vitamin-D...

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