The best supplements to take — and the ones to skip
Four supplements do most of the heavy lifting for most adults: vitamin D3, omega-3, magnesium, and (if you train) creatine. Everything else is situational. Below is the shortlist with doses, who it's actually for, and what to skip.
Check your stack in 2 minThe evidence-graded shortlist
What to skip (or at least reconsider)
- High-dose vitamin C (1,000 mg+) if you eat fruit — mostly excreted.
- BCAAs if you take whey — see the redundancy breakdown.
- Iron without a blood test — real risk of overload in men and post-menopausal women.
- Zinc from multi + immunity gummy — often over the 40 mg/day upper limit.
- Greens powders as a vegetable replacement — they don't replace fiber or satiety.
- Krill oil on top of fish oil — see the overlap.
How we grade
Grade A — multiple RCTs and meta-analyses, meaningful effect size, common underlying gap, wide safety margin.
Grade B — good evidence for a defined subgroup, or safety-net role.
Grade C — mixed or emerging evidence.
Full grading methodology on the methodology page. Reference values follow the NIH Office of Dietary Supplements.
Frequently asked questions
What are the best supplements to take daily?
Four supplements have the strongest evidence for a general adult: vitamin D3 (1,000–2,000 IU), omega-3 EPA/DHA (1–2 g), magnesium glycinate (200–400 mg), and creatine monohydrate (3–5 g if you train). A basic multivitamin is a reasonable safety net but not a headline pick.
What's the single most important supplement?
For people with indoor jobs or living above ~40° latitude, vitamin D3 is the single supplement with the widest gap between how much people need and how much they get from food and sun. Blood level target: 30–50 ng/mL.
What supplements should I skip?
Skip products you're already getting from food or another bottle: 1,000 mg vitamin C if you eat fruit, iron 'just in case' if you eat meat, greens powders if you eat vegetables, and BCAAs if you already take whey protein.
Are expensive supplements better?
Price mostly buys marketing. What matters: the right form (magnesium glycinate vs oxide, D3 vs D2, methylated B12 for some people), third-party testing (USP, NSF, Informed Sport), and a dose that matches the research — not the price tag.
How do you decide what's 'best'?
We grade each supplement on evidence strength (RCTs and meta-analyses, not single studies), effect size (does it actually do something meaningful?), safety margin (how far the effective dose sits below the upper limit), and how common the underlying gap is.