I would argue here, while this is mostly true Conny, as with all things with the human body, it depends. As you and I age, as our bodies change, and as we evolve physically, we may find that because of dietary restrictions due to some kind of illness or idioscynracy we may well need supplementation. For those who insist on (and I rather disagree on this) an uber-strict vegan diet, they need B12. I have to have more calcium as I have aged and suddenly found out that my kidney problems severely restrict a great many foods. So while I completely agree with the premise of your piece, this statement itself - while largely very accurate, borders on medical advice, for the simple fact that food is medicine is food. A fact that you clearly demonstrate in your story (and which, stunningly, the average person simply does not realize). Ancient shamans all knew the healing and/or toxic impact of foods. We are incredibly ill-informed, which is why I like your article.
We've got nearly eight billion unique physical universes on this planet, and each of us has significantly different needs, which you make an excellent argument for right at the beginning and again throught our piece. Like you point out, some nitwit argued- without medical creds- that we should eat lots of turmeric to help fend off Covid.
Okay, well, first, that isn't true, and second, I'm a bonafide hemophiliac. Turmeric is a blood thinner.
To your point. What works for A is not guaranteed to work for B.
Perhaps what is slightly more accurate might be that while yes, absolutely, if you and I consume a broad range of foods, good foods, not the shit we eat in America, we largely do not need supplements, there may well be situations wherein the body can't or doesn't absorb what it needs to be healthy. That takes intelligent sleuthing work. But that circles back to your excellent premise, which I wholeheartedly support: 1) STOP GIVING INAPPROPRIATE MEDICAL ADVICE and that includes what foods to eat and 2) STOP TAKING OTHERS' MEDICAL ADVICE that is unproven, has nothing whatsoever to do with your unique body. Do the work to find out what you need, for your age, your body, your activity level, etc. right now.