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Vitamin D supplementation and incident dementia

alz-journals.onlinelibrary.wiley.com

41–50 of 137 posts

Re: Vitamin D supplementation and incident dementia

#41

Like all studies into Vitamin D supplementation that aren’t randomized controlled trials, it’s very hard to tell apart cause and effect. Vitamin D naturally occurs when people go outside and get exposed to the sun, and going outside is correlated with all sorts of healthy traits. Also, publicity of the association of vitamin D with good health has led people who care about their health or who have access to good medi…

When evolution molds a genepool it does so with inbuilt assumptions, one the assumptions is exposure to some level of sunlight. Deviating from these assumptions would result in undefined behavior (in the CS sense) for individuals. If an individual cannot or will not expose themselves to sunlight, taking D3 is probably the best option they have.

The last time I took a casual glance at studied, it seemed that vitamin D deficiency was correlated with multiple health conditions; however, vitamin D supplementation had not clearly prevented or reversed those conditions. That is, this isn't like scurvy.

A common hypothesis was that vitamin D status was a proxy for sun exposure and not a complete explanation for those health problems.

Re: Vitamin D supplementation and incident dementia

#42

Like all studies into Vitamin D supplementation that aren’t randomized controlled trials, it’s very hard to tell apart cause and effect. Vitamin D naturally occurs when people go outside and get exposed to the sun, and going outside is correlated with all sorts of healthy traits. Also, publicity of the association of vitamin D with good health has led people who care about their health or who have access to good medi…

> Vitamin D naturally occurs when people go outside and get exposed to the sun, ... Not sure where you are living? If I go outside in winter (+2 months around) I need gloves, cap, scarf. Literally only a little portion of my face gets some sunlight until 5pm. Then it is dark! I live in Germany! So, this isn't an argument for a lot of people in cold countries or dark countries. Mostly both.. Exposing to the sun is ver…

It's hard to find good answers on actual timelines, but vitamin D is fat soluble and you don't become insufficient after just a week of sitting in the dark.

Re: Vitamin D supplementation and incident dementia

#43

I dove deep into Vitamin D supplementation research during Covid. The tl;dr as I understand it - and bear in mind I'm a layperson in this - is that while Vitamin D deficiency correlates to many bad things, taking Vitamin D doesn't help . It does raise your level as it shows up in blood tests, but the bad things still happen. Except for some very specific issues. I have a mild deficiency and used to take Vitamin D. I…

There have been many other studies on vitamin D and COVID-19. Recommend reading them all before forming a conclusion.

https://vitamin-d-covid.shotwell.ca/

Re: Vitamin D supplementation and incident dementia

#44

Earlier quoted context omitted.

I wouldn’t say I have followed the science but my doc prescribed 2000 IUs daily and it definitely makes a noticeable difference in a gloomy winter

What kind of a difference have you noticed? I also take 2000 IUs, but I haven't noticed any significant difference in how I feel since I've started taking it.

I personally just felt a little sadder and lower energy in my first winter in a gloomy climate. The vitamin D just made me slightly more chipper and energetic.

I didn’t do a blood test pre vitamin D but tested recently and my levels look good, so my doc said to just keep on it.

Wouldn’t say the difference is transformative but it’s helpful.

Re: Vitamin D supplementation and incident dementia

#45

Earlier quoted context omitted.

> Vitamin D naturally occurs when people go outside and get exposed to the sun, ... Not sure where you are living? If I go outside in winter (+2 months around) I need gloves, cap, scarf. Literally only a little portion of my face gets some sunlight until 5pm. Then it is dark! I live in Germany! So, this isn't an argument for a lot of people in cold countries or dark countries. Mostly both.. Exposing to the sun is ver…

It's hard to find good answers on actual timelines, but vitamin D is fat soluble and you don't become insufficient after just a week of sitting in the dark.

More like six months.

Re: Vitamin D supplementation and incident dementia

#46

Earlier quoted context omitted.

> Vitamin D naturally occurs when people go outside and get exposed to the sun, ... Not sure where you are living? If I go outside in winter (+2 months around) I need gloves, cap, scarf. Literally only a little portion of my face gets some sunlight until 5pm. Then it is dark! I live in Germany! So, this isn't an argument for a lot of people in cold countries or dark countries. Mostly both.. Exposing to the sun is ver…

It's hard to find good answers on actual timelines, but vitamin D is fat soluble and you don't become insufficient after just a week of sitting in the dark.

I am talking about months of actual lack of sunlight, not a week.

I for myself know 2 friends which diagnosed with vitamin D insufficiency. Because we are relatively young this lead to bone problems while doing sports. Without sports it wouldn't be recognized.

Re: Vitamin D supplementation and incident dementia

#47

I’ll try to get 15-30 min of sun exposure without sun screen in the warmer months each day. Feel immensely better during then, to a point where I’ve seriously considered moving somewhere warmer without real winter months.

Even during winter I try to get some exposure on rare sunny days. The other day we had a very clear day so I sat out on the porch facing the sun for fifteen minutes... in -5c.

Re: Vitamin D supplementation and incident dementia

#48

I've been taking 1000 IUs daily, for the last 20 years, skipping summers (during which I would attempt sun exposure), while continuously being within acceptable medians for my age. I sure hope what I am typing now makes sense :-)

Older folks can't make D naturally, so you may want to skip your summer skipping soon.

Re: Vitamin D supplementation and incident dementia

#49
post #3

Hey people who follow the science: As an “indoor human”, how much should I be taking? (TIA!)

I would advise taking a K2 MK7 supplement with D3, or get a supplement that contains both. Personally, I take one capsule a day that contains both 3000IU of D3 and 100μg of K2 MK7. D3 by itself can cause high calcium levels, to the point of toxicity in very high doses. The K2 moves the calcium from the blood to bones.

The Japanese recipe for fermented soybean, called Natto is an abundant natural source. Not easy to find in the US though. I've found it offline at Japanese groceries and one boutique grocer at an exorbitant price so far.

Re: Vitamin D supplementation and incident dementia

#50

Like all studies into Vitamin D supplementation that aren’t randomized controlled trials, it’s very hard to tell apart cause and effect. Vitamin D naturally occurs when people go outside and get exposed to the sun, and going outside is correlated with all sorts of healthy traits. Also, publicity of the association of vitamin D with good health has led people who care about their health or who have access to good medi…

> Vitamin D naturally occurs when people go outside and get exposed to the sun, ... Not sure where you are living? If I go outside in winter (+2 months around) I need gloves, cap, scarf. Literally only a little portion of my face gets some sunlight until 5pm. Then it is dark! I live in Germany! So, this isn't an argument for a lot of people in cold countries or dark countries. Mostly both.. Exposing to the sun is ver…

I had thought that it was possible to get vitamin D from moderate sun exposure in the winter and went looking for info to refute your post. Turns out you are right and I was wrong: https://www.nytimes.com/2022/12/06/well/live/vitamin-d-defic...

People living above the 37th parallel, basically the tropics, may not be getting enough in the winter, because the sun isn't strong enough to provide it.

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