- It won't make any effect for around month once you start taking it
- it only has effect if you have serious deficiency.
I used to be sick really easily for years, always tired. Finally got doctor to make blood tests and if normal level 100, min is 60, then my vitamin D levels were 12. Ofcourse my body immune system struggled. After started with suppliments got more energy, got less often sick. Felt like a normal person.
There is also other extreme, taking too many will have negative effect. I've experienced them myself.
I do live in a northern climate (imagine Finland) with long dark winters and only sun time is spend in the office.
75% of the population is suboptimal in Magnesium, without Mg - our ability to absorb D diminishes, even with supplementation.
Vitamin D must be supplemented with Vitamin K2 MK7 to ensure the extra calcium generated is deposited in the bones and not in the soft tissues (hypercalcemia)
Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5786912/
Magnesium Supplementation in Vitamin D Deficiency. https://www.ncbi.nlm.nih.gov/pubmed/28471760
Low magnesium levels make vitamin D ineffective https://www.sciencedaily.com/releases/2018/02/180226122548.h...
Vitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease https://www.mdpi.com/1422-0067/20/4/896/htm
Vitamin K2: A Vitamin that Works like a Hormone, Impinging on Gene Expression https://www.intechopen.com/books/cell-signalling-thermodynam...
Also, vitamin D really shouldn't be taken any other time than before noon.
(Not sharing this for you in particular, just for anyone reading who decides to try vitamin D supplementation for the first time. Doctors aren't always sharing she vital info about how to take vitamin D)
I'm sure I could go find sources, but it might be helpful if you link them here. It's hard to believe comments that give medical information and disparage doctors.
Does this advice apply to people that work night shifts?
Specimen 2) - The first comment on hackernews: Unfounded anecdata
What a disappointment.
So I am skeptical of supplements as a rule. Of course there are a couple of odds, like iodine, which is so beneficial to supplement in general community, that it is added to table salt as default, you only skip if you have specific conditions like thyroid problems.
I wish there were more research or comments on possible harms and disadvantages of excessive use of vitamin D, than I think I could more easily decide to use.
If you follow the daily dosage information, you won't even get near harmful levels of vitamin d. Recommended is about 600 IU daily. If you take 60.000 on a daily basis for months, you build up toxicity.
For that you typically need to take 30 pretty strong 2000 UI pills on a daily basis for months, while ignoring the label that states each pill is typically 250% of the daily recommended amount, and the instruction which notes the tolerable levels max out at just two daily pills.
Toxicity is extremely uncommon. Whereas deficiency is extremely common. Up to a billion people are expected to have some form of vitamin d deficiency.
That's not to say it's not a problem, but rather that it's very rare, nothing like say an opioid overdose problem. As with all things, balance is key. You can overdose on 5 cents of water in the span of 5 minutes. Acute vitamin d overdose is known to happen if you take something like 300-1000 pills of 2000 UI over a period of days, which is pretty insane.
“ It also estimated that 8895 IU of vitamin D per day may be needed to accomplish that 97.5% of individuals achieve serum 25(OH)D values of 50 nmol/L or more.”
Hypervitaminosis D symptoms appear several months after excessive doses of vitamin D are administered.
"however, findings are inconsistent"
I think it might be worth for people here to reanalyze everything.
The effect sizes seem large and clinically significant.
So this is big if true.
Luckily we have a large supply in house thanks to being forgetful and needing it for the baby. My wife has a large supply of girly multivits and I managed to score a months supply of multivits.
The NHS does recognise vitamin D deficiency as an issue.
In the UK, a science advisory body (Scientific Advisory Committee on Nutrition) published a 300 page report of the evidence on vitamin D and health in 2016. Their conclusion: adults and children over one in the UK should have at least 10 micrograms of vitamin D every day. For some people this may mean taking a vitamin D supplement. People who have a higher risk of vitamin D deficiency are advised to take a supplement all year round.
Here is an overview of the guidelines on the NHS website which includes a link to the 300 page scientific review.
https://www.nhs.uk/news/food-and-diet/the-new-guidelines-on-...
However, the specifics do matter; see e.g. https://www.gwern.net/zeo/Vitamin-D - this is n=1 but consistent with many other n=1 self-experiments I'm familiar with; personally, my sleep is improved with increased protein consumption AND 10,000 IU D3 before 10AM (Both contribute; I've not gone about 10,000 IU, but 5,000 UI has a much lesser effect)
I have not find a peer reviewed time-of-taking-D3 paper when I looked, but D3 is recognized as a timing mechanism ("Zeitgebber") in many papers I've found.
So while you not everyone who is feeling tired or depressed will have a vitamin D deficiency, I'd say that it absolutely can cause those symtoms.
