Also, depending on your level of sun exposure and possible deficiency, you should probably supplement MUCH more than what has been usual for decades. You will

Also, depending on your level of sun exposure and possible deficiency, you should probably supplement MUCH more than what has been usual for decades. You will find a max of 1000 IU and many supplements at daily doses way lower than that (300 - 700 IU). This is likely wrong: "Since all-disease mortality is reduced to 1.0 with serum vitamin D levels ≥100 nmol/L, we call public health authorities to consider designating as the RDA at least three-fourths of the levels proposed by the Endocrine Society Expert Committee as safe upper tolerable daily intake doses. This could lead to a recommendation of 1000 IU for children <1 year on enriched formula and 1500 IU for breastfed children older than 6 months, 3000 IU for children >1 year of age, and around 8000 IU for young adults and thereafter. Actions are urgently needed to protect the global population from vitamin D deficiency." [1] [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/