For context I’m listing the original science paper, there's more to the story than vitamin D toxicity.
https://www.cmaj.ca/content/191/14/E390
A 54 yr old Canadian man with gout, hypertension and a family history of polycystic kidney disease took a trip to Southeast Asia where he spent 6-8 hours a day sunbathing (while taking 8,000 to 10,000 IU’s of vitamin D daily). The man had been taking the dosage for 2.5 years per his naturopaths prescribed instructions, he was not counseled on toxicity risks. This led to the man’s decreased kidney function.
After returning home the man was referred to a nephrology clinic. Doctors offered the glucocorticoid therapy but the man refused due to weight gain concerns, so they offered him hydroxychloroquine to help return his body to normal, and after a year's treatment it did. He was never at death's door, he is however left with stage 3b kidney disease, treatable yes, not fatal. The man's doctors stated his kidney injury was likely worsened by his volume depletion from diuretic use, prolonged heat exposure and pre-existing hypercalcemia from vitamin D toxicity. This was in 2019.
If you live in areas where you're not getting enough sunlight, chances are you'll need to supplement with vitamin D. If you get enough sunlight during the rest of the year maybe you don't require supplemental vitamin D. Vitamin D toxicity is rare, you'd have to take exceedingly high amounts for months on end.
https://www.mayoclinic.org/healthy-lifes...q-20058108
There is a variant to vitamin D toxicity, and it's a specific gene called CYP27B1, this gene deactivates excess vitamin D from the liver. More information is listed in the research paper, it's quite interesting. Wee2er, either you're getting enough sun exposure or you might be missing the specific gene eliminating excess vitamin D from your liver, essentially making your vitamin D level higher on a normal dosage of vitamin D. Talk to your doctor about further testing for the CYP27B1 gene to be sure if you'd like.
It's great to bring awareness about vitamin D toxicity. I get that, as stated in the paper "Patients with CYP24A1 mutations may be at an increased risk of vitamin D toxicity"...which coupled with the man's sun exposure (and a couple of other things) contributed to his kidney disease. However, I don't think we need to warn people off from taking normal RDA of Vitamin D amounts.
How much vitamin D do you need?
Based on the evidence for bone benefits, however, the IOM panel increased the RDA for vitamin D to 600 IU for people up to age 70 and to 800 IU for those over 70. That's a fairly sizable boost over the previous recommendations of 200 IU per day through age 50, 400 IU for ages 51 to 70, and 600 IU for ages over 70. The IOM also raised the safe upper limit of daily intake for most age groups from 2,000 to 4,000 IU.
https://www.health.harvard.edu/staying-h...o-you-need
The rda of Vitamin D3 is:
The Endocrine Society states 1,500–2,000 IU of supplemental vitamin D
https://ods.od.nih.gov/factsheets/vitami...fessional/
