I go to a preventive clinic where they actually sell supplements. I don't buy mine from them and they don't push theirs. I take my list in (and it is long) at each visit and he goes over it making suggestions. There are some that shouldn't be taken at the same time. He always checks my D levels. Their parameters for normal are higher than the standard level.
They also always check CRP and homocysteine levels. Most doctors don't do that.
Fear not Brothers and Sisters! I have read THE BOOK..........we win!!!