alt Hacker NewsThis guy will get you killed. It is reasonable to maintain a blood level of about 45 ng/mL. This often requires 5000 IU/day, perhaps less in seniors with weaker kidneys, or those with heavy sun exposure which is dangerous for other reasons. You don't need to see a doctor for this, but you do need to get the test done every year or two. Personally I prefer not involving a doctor for any of it.
Nobody disputes that excessive vitamin D is not good, but maintaining a blood level below 45 ng/ml also is not good. Covid studies had ascertained that a level of at least 50 ng/ml was optimal.
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> This guy will get you killed
Yeah, no. Advising people to correct Vitamin D deficiencies but to avoid overdosing is correct.
I quoted the study. The study agrees that excessive Vitamin D consumption is not good.
> 5000 IU/day
Ironically these "IU/day" estimates are bogus. Direct ~noon sunlight at the equator for fair skinned individuals produces (full body exposure) 15-50k IU/hour of D3 equivalent, depending on the estimate. You clearly don't see people dropping dead after two hours in the sun.
GPT response For a fair-skinned adult, nude or essentially whole-body exposed, at solar noon near the equator under a clear sky, a reasonable order-of-magnitude estimate is:
Exposure Approx. D3-equivalent produced ~3 min ~2,500–6,000 IU ~5 min ~4,000–10,000 IU ~10 min ~8,000–20,000 IU ~10–15 min / ~1 MED ~10,000–25,000 IU >20–30 min does not keep increasing linearly
The best-known experimental anchor is that roughly one full-body minimal erythema dose (1 MED)—enough UV to cause faint redness later—is associated with a vitamin-D effect comparable to ingesting about 10,000–25,000 IU (250–625 µg) of vitamin D3. Reviews note that this estimate has also received support from outdoor solar-exposure studies, although the original experiments used artificial UV sources. https://pmc.ncbi.nlm.nih.gov/articles/PMC3257661/ study