In December by chance I put a pack of Vitamin D into my shopping basket. I did not think much, thought to take 1000IE but then decided that for the first week I take 3000 to catch up. Muscle pain went and control over eating improved. I did not expect any changes based on past experience with 1000 but this time I could not ignore it (age can play a role) and I stayed on 3000. Tests a month later showed I was just not deficient any-more. I continued on the regime and started having improvements in long running skin issues to the extent my dentist noticed. It may not be a miracle drug but one should not underestimate cumulative impact individual factors, age and lifestyle changes (less sun) that may change levels and demand.

2 years ago i caught some repeated strep throat infection, repeated like 6-8 times - because my original general doctor said that with low CRP there is no way i have bacterial infection... before i found a doctor who finally did proper swab and ABTs - but i was so far gone that i got horrible headaches, muscle pain, stinging, absolute weakness... on top of that i cought covid and proper flu. Totally crazy, when they did mi vitamin D it was at 10% of minila recomended value. I god vit D and some immunity pills(pigs blood cells - this is questionable). I was slurping the vitamin D every day and in couple of weeks I was almost back to normal.

I have seen neurologists, imunologist, infection diseases specialist, everything is boreliosis qack and even somatic doctor...

Funny thing is before i got sick i spent 3 months on tenerife, so no reason for me to have low vit D. But it was probably depleted by immunity trying to fight the repeated infections.

so yeah, get your vitamin D checked if you feel weak, low on mood or anything out of zen

I used to take 4k IU + K² and think that I'm covered, since 4K units was a lot.

I landed on just above deficient when tested.

My wife was on kind of same regime, but didn't follow it very strictly. She was deficient, but not extremely.

It was quite surprising, because I got warned when buying 4k unit tabs that they were quite strong and pharmacy clerk suggested taking less.

What exactly changed?

I am deficient, too, and take supplements (rare liver disease).

I wonder if taking mushrooms soaked in the sun improves absorption compared to supplements?

That doesn't undermine OP's point. Being deficient is unhealthy. But that doesn't mean an overabundance makes you healthier.

How do you know the changes aren’t placebo?

As the article mentions, we pretty much don't see improvements with supplementation.

Yeah, I wish the article had brought Vitamin K2 into the mix since that seems trendy to pair with your D3 these days.

Indeed: “Vitamin D deficiency in western dwelling South Asian populations: an unrecognised epidemic” … “27–60% of individuals, depending on season”

https://pmc.ncbi.nlm.nih.gov/articles/PMC7663314/?utm_source...

It has never been established that darker people require the same amount of D as lighter. The supplement industry plays on these fearmongering to boost sales.