When you look at large-scale studies of OTC vitamins, you quickly realize that the absorption on most of them is very poor; they don’t really move the needle very much. In most cases, you will be better off if you address vitamin and micronutrient deficiencies through diet rather than attempting supplementation.
I’m D deficient. I took D supplements for a long time; m D levels never significantly increased.
n=1, best study ever.
https://www.nature.com/articles/s41574-021-00593-z
When you look at large-scale studies of OTC vitamins, you quickly realize that the absorption on most of them is very poor; they don’t really move the needle very much. In most cases, you will be better off if you address vitamin and micronutrient deficiencies through diet rather than attempting supplementation.