Enough with the philosophy. Or maybe it's applied psychology. Whatever.
As soon as knowledge about vitamins and other nutritional needs came out, there were snake oil salesmen to take advantage. Tired? Take these vitamins, or Geritol with its iron.
Now we know or suspect that iron can be bad for you, that you may be healthier as long as you are not actualy anemic.
So it is with the other fads.
Back 40+ years ago, Nobel Prize-winning biochemist Linus Pauling made front page news when he claimed taking Vitamin C would cure/prevent colds. Talking doses measured by grams, megadoses. Turned out not to be true.
[30 years later we would hear that magnesium ion in cough drops or nasal sprays would cure colds; ot sure how that came out except that few are sucking magnesium cough drops today.]
Then there was the vitamin megadose fad. Early 1980s. Some viamins of course are toxic in high doses and this may even include a water soluble B vitamin or two. So that fad faded, though many vitamin pills today claim to have megadoses of some vitamins.
Then there was the calcium fad. No question, a lot of us need calcium. But there are problems with absorption and with side effects if you get too much. One time 10 years ago I caught my mom gulping a handful of calcium tablets; I stopped her and gave her a lecture which did not sink in.
And there was the Vitamin E fad, it being claimed that Vitamin E would be a preventive/treatment for cardiovascular problems. Some learning that Vitamin E deficiency affected reproduction in rats though they could gulp a mouthful and end up as a sex machine. Not so.
Vitamin A fad. Turned out that taking Vitamin A was correlated to higher incidence of some kinds of cancer, not lower. End of fad. Vitamin A btw is one of the genuinely toxic vitamins in high enough doses. For more on this, Google Mawson Expedition (the explorers fed on the liver of the sled dogs they killed and their hair nd skin started sloughing off).
Some things it seems you do want to take. Vitamin D, the new supervitamin. Calcium in absorbable form, because most of us do not get enough. Aspirin is the genuine wonder drug for those if us who can take it without ill effects. A multivitamin because it doesn't hurt--unless there are dangerous impurities in the pill, which have been observed. And I've started taking a magnesium zinc supplement.