Original title "Vitamin D Supplementation: A Review of the Evidence Arguing for a Daily Dose of 2000 International Units (50 µg) of Vitamin D for Adults in the General Population" compressed to fit within title limits.
As someone who has served as a reviewer for several MDPI journals, I personally haven’t found their overall quality to be particularly high—which was a factor in my decision to stop reviewing for them. Of course, it’s possible that some specific journals or articles are exceptions, but I would encourage readers to critically evaluate work published by MDPI on a case-by-case basis.