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The worthlessness of Vitamin D is mildly exaggerated

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Re: The worthlessness of Vitamin D is mildly exaggerated

#221

Post by wongarsu »

Aurornis wrote: post #7

This is a refreshingly balanced and honest analysis of Vitamin D studies. The strongest evidence for Vitamin D is in people who are severely deficient. Bumping up to a normal range can provide some improvements. The health influencers started noticing that the Vitamin D studies coming out weren't matching their original hype for Vitamin D, so many pivoted to trying to make claims that most people are severely deficie…

Seemingly any decent way to tune in a steady-state supplementation involves multiple iterations of the "get blood test, adjust dosage, repeat" loop

On the other hand, when our body synthesizes Vitamin D itself it seems to regulate that process to prevent overdose. So I've just settled on supplementing in the winter based on my best estimate of the correct dosage, then let my body do its thing in the summer. No issues so far, and supplements have had a major impact on my fatigue/energy/depression levels in the winter

Re: The worthlessness of Vitamin D is mildly exaggerated

#222

Post by HPsquared »

bryanrasmussen wrote: post #218
HPsquared wrote: post #91

Earlier quoted context omitted.

More hours of sun, but it's less intense.

Is it really less intense? When I go out on a sunny day in Denmark it is murder. When I go out on a sunny day in Italy it's generally just overall warm. At any rate another factor is that in the Northern regions it's my experience people do their best to soak up as much sun as possible.

The sun is at a lower angle from the horizon at higher latitudes. It passes through more atmosphere, losing some UV, and also the surface irradiance on the ground (energy per unit land area) is lower.

Re: The worthlessness of Vitamin D is mildly exaggerated

#223

Post by HPsquared »

ludicrousdispla wrote: post #210
codethief wrote: post #117

Earlier quoted context omitted.

The sun in northern countries in summer is less intense?

I found this resource which shows that sun intensity in June in northern Europe is similar to that in sub-Saharan Africa (in June). https://physics.weber.edu/schroeder/ua/EarthCirclesAndSunRay... https://physics.weber.edu/schroeder/ua/SunAndSeasons.html

At the equator, the sun is highest at the equinoxes (March and September) and lowest at the solstices. Outside the tropics, the sun is highest at the summer solstice (June or December) and lowest at the winter solstice.

Re: The worthlessness of Vitamin D is mildly exaggerated

#225

Post by dgfl »

TeMPOraL wrote: post #182
Broken_Hippo wrote: post #166

Earlier quoted context omitted.

Yeah, kinda. I moved from Indiana to Norway - Trondheim, which is about in the middle of the length of Norway. During the summer, I can read outside at night even though the sun technically goes down for about 4 hours in June. It never gets darker than twilight. A few clouds means you might just have sunset all night. The sun does get surprisingly hot and very warming if we happen to have a sunny day. Jacket in the s…

> The reason for this is that the sun is at a low angle, so it hits more of your body than it does when the sun is overhead - like you'd get in Australia. This also means that while you need some sunscreen during the day - from about 10 to 5 - it doesn't burn as much. Not sure if I parse this correctly - I'd imagine you need more sunscreen at "low angles" due to more severe and longer exposure? Low angle -> more body…

I’ve found the UV index forecasts to generally be a good metric, so try looking at those for various locations. The main factor here is that the lower the sun is from the horizon, the more its light will be absorbed by the atmosphere due to the longer path. The maximum altitude that the sun will ever reach is (90° – (latitude – 23.4°)), so at the 60°-ish of Scandinavia it’s rarely more than 50° in the sky. It’s a very noticeable difference even in the summer. In my experience (born in southern Italy, pale-average, currently living in Sweden) it’s almost impossible for me to get sunburn in daily life in Sweden even without sunscreen. Definitely not so further south.

Re: The worthlessness of Vitamin D is mildly exaggerated

#226

Post by normie3000 »

Aerroon wrote: post #40

The survey in the article that assessed vitamin D deficiency was a bit odd: > Because physical exams are performed in mobile vans in NHANES, data could not be collected in northern latitudes during the winter; instead data were collected in northern latitudes during summer and in southern latitudes in winter. To address this season-latitude aspect of the NHANES design, we stratified the sample into two seasonal subpo…

> data were collected in northern latitudes during summer and in southern latitudes in winter

And what were they doing for the other 9 months of the year?

Re: The worthlessness of Vitamin D is mildly exaggerated

#227

Post by da_chicken »

bryanrasmussen wrote: post #218
HPsquared wrote: post #91

Earlier quoted context omitted.

More hours of sun, but it's less intense.

Is it really less intense? When I go out on a sunny day in Denmark it is murder. When I go out on a sunny day in Italy it's generally just overall warm. At any rate another factor is that in the Northern regions it's my experience people do their best to soak up as much sun as possible.

I could believe that if you were near the coast.

I grew up in central Michigan and thought the same about the sun until I spent a few years in southern Arizona. The sun there feels like a heat lamp in summer. The low humidity makes the atmosphere absorb less energy. Although it feels like it's about 5 C cooler than it actually is because sweat evaporates so quickly, but once it gets to 43 C you actually just feel vaguely ill just going outside. Standing in the sun is just not something you do. It's a very unique experience to lick your lips and have your tongue feel cold.

Of course, neither of those were as bad as Houston in August. It was 38 C and 98 % relative humidity. And, I will point out, it had not rained. That's just what it's like. You walk outside and your glasses instantly fog up and you feel like you desperately need to shower.

Re: The worthlessness of Vitamin D is mildly exaggerated

#229

Post by charlysisto »

waffle-fry-pan wrote: post #200

tl;dr: The combination of vitamin D/MG cured heart arrythmia and mild depression I suffered from for almost 20 years, so I do not think it is worthless. I had ventricular extrasystoles for a very long time of my life (18-37). This is a mostly harmless arrytmia that feels like one beat out of the normal rhythm. Around 18, I noticed it for the first time. It came and went, usually I had this for ~3 weeks and then it wa…

Yes magnesium seems to be quit a common deficiency because the heavy use of fertilizer depletes the density of minerals in the food chain. Also magnesium is a very important co-factor in the use of Vit D, so supplementing with a magnesium deficiency might not be of much use. Sadly this seems overlooked in most studies
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