The supplement industry sells certainty, which is the one thing the evidence rarely offers. A small number of products have genuine research behind them. Most have a plausible mechanism, a study in rodents, and a marketing budget.
These articles grade each one in the same three tiers we use everywhere on this site — has been shown to, research suggests, may help — and name who should skip a product entirely, including the medical situations where "harmless" stops being true.
One of the few supplements with substantial evidence behind it — and specific caveats after 40. What it does, who it may suit, who should ask a clinician first, and what the marketing overstates.
The most-bought supplement in the world has the least impressive evidence behind it. What multivitamins do, who genuinely benefits, and why "insurance" is the wrong metaphor.
Fish oil has one well-proven effect, several plausible ones, and a great deal of overreach. What EPA and DHA actually do, what dose, and whether fish beats capsules.
The large trials disappointed on most of what vitamin D was sold for. Correcting a real deficiency still matters. Here is where the line falls, and what dose and testing actually make sense.
A practical walkthrough of the Supplement Facts panel — serving size games, proprietary blends, elemental weights, third-party marks, and the wording that means nothing.
No diagnosis. No pressure. Just a clearer place to start.