Quote:
During this time, we have admitted over 4700 patients, the vast majority of whom agreed to supplementation with either 5000 or 10,000 IUs/day.
There have been no cases of vitamin D3 induced hypercalcemia or any adverse events attributable to vitamin D3 supplementation in any patient.
Three patients with psoriasis showed marked clinical improvement in their skin using 20,000 to 50,000 IUs/day.
The average serum calcium level in these 2 groups was 9.5 (no D3) vs 9.6 (D3), with ranges of 8.4 to 10.7 (no D3) vs 8.6 to 10.7 mg/dl (D3), after excluding patients with other causes of hypercalcemia.
The average intact parathyroid hormone levels were 24.2 pg/ml (D3) vs. 30.2 pg/ml (no D3).
In summary, long-term supplementation with vitamin D3 in doses ranging from 5000 to 50,000 IUs/day appears to be safe.
Quote:
Conclusion
Daily oral intake of vitamin D3 ranging from 5000 IU/d to 60,000 IU/d for several years was well tolerated and safe in both our patients and staff. The mean 25OHD blood levels in our patients appear to take around 12 months to plateau on 5000 IU/d and 10,000 IU/d.
The average 25OHD values we observed in patients taking 10,000 IU/d at 12 months (96 ng/ml) and 16 months (97 ng/ml) are almost identical to what is currently considered to be the upper limit of normal (100 ng/ml) and are approximately
an article from 2019
this article has nothing to do with our friend Dr Judson Somerville

vit-D levels are checked on almost everyone in adult PCP, endo, neuro, etc clinics;
without supplementation, levels are usually <35ish -- and this is in sunny states -- this is suboptimal
even though the pharmacokinetic risk for D-toxicity hypercalcemia levels is ~250-300+, dont need to drive people up to that level.
the probable near-max therapeutic levels are going to be ~100-150, and clinically (on the population, not individual standpoint), this appears to be quite safe
typical vit-D recs, IMO, should be -- D3 (not d2) 2500 to 5000 IU daily w/ (fatty) food w/ K2-mk7 ~100mcg