The two fundamental issues are:

Issue 1: That every supplement has:

-a chance of harmful interactions with other drugs/supplements (and as you take more and more, the number of potential interactions grows quadratically – like supplements squared)

-a chance of contamination (e.g., with lead, or with compounds not mentioned on the label), which is not as rare as one may think

-a chance of negative interactions with your biology (e.g., nearly every studied medication is found to cause some side effects more often than a placebo)

Issue 2: That almost all supplements, when eventually *rigorously* tested on general healthy populations (i.e., they are not populations with a specific disease or going hungry etc.) show no health benefits. So the risks from Issue 1 are unlikely to be compensated for.

Of course, this does not mean that ALL supplements don’t work. For instance, creatine likely helps build muscle mass for those trying to bulk up, most strict vegans should supplement with vitamin D and B12, and people with darker skin living in less sunny climates are at elevated risk for vitamin D deficiency. Omega-3s are likely not harmful and may even give you some benefits. If you test low in an essential vitamin or mineral, that’s, of course, a good reason to supplement it. And there are some impoverished areas of the world where basic nutrition is routinely not met, in which case supplementation with vitamins/minerals can be life-saving. Multi-vitamins from reputable companies that undergo third-party testing are at least very unlikely to harm you much unless they include mega doses. But once you start taking large doses, or compounds your body doesn’t normally encounter, and especially when you start taking many at once, supplementation becomes riskier.

One other caveat: some of the “all in one” kinds of supplements put so little of many of the compounds in the supplement that while, thankfully, they aren’t likely to hurt you, it also pretty much rules out the benefit as well. Dose-response cuts both ways.

Overall: my point is not that all supplements are useless, but about the risk/reward profile of taking *tons* of them at once: that ordinary people end up worse off (unless the dosages are too small to realistically get any benefit).

This piece was first written on December 6, 2025, and first appeared on my website on December 22, 2025.