You need to treat D3 as a hormone with an ideal range. When your blood levels gets too high (typically over 100) you have trouble sleeping and might have restless leg syndrome. When it's in the ideal range (60 - 80) you sleep like a baby.
Dr Gominak has done a bunch of research on D3 levels and sleep. Her RightSleep program will walk you through how to properly supplement into the ideal range. She has a few videos on YouTube with all the background info. This is my current favorite: https://www.youtube.com/watch?v=n1Qm5x7Lxgc
Having said that, most doctors don't have a clue about D3 dosing. You'll have to do some research.
Most people will overshoot in a month or two if they take 10,000 a day, but I know of people that have taken that level for long periods without ever going too high. It's super personalized.
Age also has a big effect on serum levels. When you are mid-40s+, you cannot absorb D3 as well, and it takes a significantly higher dose to get your serum levels up. This is why testing is important.
It is also important to take K2 when you are taking higher doses of D3. Even if you have a higher than normal serum level, K2 mediates the metabolism of D3, and prevents issues. I've seen numerous examples of this, verified by CAC tests which consistently score 0 in people taking 10,000 IU of D3 with 100mg K2 for extended periods of time.
Also note that Vit D increasing is fairly slow (my vit D was low and 10k IUs was my prescription for 4 weeks) so you might not see the consequences for a long while and therefore might not attribute them to the supplementation at first...
Can you point to links on consequences of overconsumption? I wasn't aware of any major downsides to consuming vitamin D in this dosage range.
It seems like one issue is restless leg syndrome, but with an issue like that, you can just shoot high anad lower your dosage if you discover that to be an issue.
The unfortunate problem in the US is that those suffering most severely from many of the symptoms of vitamin D deficiency are often unable to obtain healthcare, so a lot of people out there are left to make guesses their own healthcare on issues like this. Getting vitamin D serum levels tested is a luxury reserved for those in first world countries.
I'm very skeptical of anything on a technical field like nutrition coming from a general news source like CNN. Most of what they report about fields I'm an expert in is straightforwardly incorrect, so I can only guess that they're equally incorrect about nutrition.
Even if they're correct, it's hard to find any useful information here. They mention three numbers: 150,000 IU, 50,000 IU, and 4,000 IU. The 150,000 IU and 50,000 IU examples exhibited serious symptoms, but the number mentioned a few posts up is 10,000 IU. The 4,000 IU number is mentioned in the sentence, "A 2017 study found 3% of Americans took more than the tolerable upper limit of 4,000 IU daily for adults, thus putting themselves at risk for toxicity." But there's no discussion of what symptoms would be experienced at this level of toxicity.
As I said above, if it's just restless legs, it doesn't seem unreasonable to try the dose (10,000 IU) and lower it if you experience restless legs. Obviously it's better to get a blood test, but as I said before, not everyone has access to that kind of healthcare.
Dr Gominak has done a bunch of research on D3 levels and sleep. Her RightSleep program will walk you through how to properly supplement into the ideal range. She has a few videos on YouTube with all the background info. This is my current favorite: https://www.youtube.com/watch?v=n1Qm5x7Lxgc
Having said that, most doctors don't have a clue about D3 dosing. You'll have to do some research.
Most people will overshoot in a month or two if they take 10,000 a day, but I know of people that have taken that level for long periods without ever going too high. It's super personalized.