3 HN users recommended this explainer3 months2017–2020score 3.5
Years with an HN recommendation, 2007–2026
HN commenters point to it in vitamin D threads as a thorough walkthrough of why deficiency may matter.
Ivor Cummins gives an 82-minute presentation on the history and science of vitamin D and human health. He draws on expert interviews to argue that sun exposure and vitamin D status are linked to many chronic diseases.
Proper supplementation (read: not what is currently recommended) of Vitamin D was found to reduce all-mortality causes (including cancer, diabetes, heart attacks, etc) by as much as 50%-70%. To get to that level of 40-50 ng/ml 25(OH)D, you need around 8,000-12,000 IU per day (depending on body mass). It was also found to reduce flu occurences by as much as 70%. This is starting to look like a super important vitamin, even for "healthy individuals that work outside" - let alone everyone else that stays all-day indoors. It also seems to have a huge effect on sleeping well, as it's apparently what the body needs to repair itself properly at night. I highly recommend these videos: [this video] [link] Also, you should combine it with Vitamin K2, another hugely important vitamin most of us are likely lacking, that works in conjunction with D: [link] [link] [link]
Argues vitamin D supplementation benefits are underappreciated
More studies referenced here, also showing ~55 ng/ml being optimum for maximum health benefits. The current recommendations are way below that. Well worth to watch the whole video: [this video]
Few months ago I head how vitamin D is associated with COVID-19 outcomes and went into a rabbit hole to find more information about wtf is Vitamin D, and how our bodies use it/need it. There are two videos I found particularly informative. 1. [link] Cost/Benefit of Optimal Health with Sunshine Vitamin D William B. Grant, PhD 2015 2. [this video] D is for Debacle - The Crucial Story of Vitamin D and Human Health Ivor Cummins BE(Chem), CEng MIEI 2014
Informative explanation of how the body uses vitamin D
According to the study in the other HN link here, they made an error in calculating how much Vitamin D you need. The medical community also seems to think that 20 ng/ml is when the deficiency starts, when in reality it's more like 40. Some studies have shown that you can see benefits upwards of 60 ng/ml. Other research has shown that Vitamin D helps with sleep in the 60-80 ng/ml range. I've seen many people on Reddit say that their blood tests level came out at 5-10. That's crazy. Get your 25(OH)D level checked. Some of the studies that have shown "no improvement" from Vitamin D saw that result mainly because they were still prescribing far too little Vitamin D (yet still higher than the RDA). 10,000 IU may be necessary just to maintain your level. However, you also have to keep in mind that you won't be getting D only from the supplement, so throughout the year you should actually increase your Vitamin D level as you get more sun exposure. Meanwhile the 10,000 IU (which by the way is "only" 250 micrograms ) will maintain those high levels. Then, in the second year, you may further increase your Vitamin D level as you once again get more exposure in the sunny days. So you should check your Vitamin D at least after a year, to ensure your levels aren't too high. After you're stabilized you should need around 5,000-7000 IU, but it's really dependent on each person's needs, so you'll have to figure out on your own through trial and error. However, you also need to keep in mind th
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