Best Vitamins and Supplements: Which Ones Most People Actually Need
Most people eating a varied diet need few supplements. See who benefits from vitamin D, B12, folic acid and iron, and why multivitamins don't prevent disease.
By the editorial team · Updated Oct 14, 2026 · 2 sources cited
The best vitamins and supplements are the ones that fill a real gap. Vitamin D for people with little sun, B12 for vegans and adults over 50, folic acid before pregnancy, and iron when a test shows you're low have the clearest benefits. The US Preventive Services Task Force found insufficient evidence that multivitamins prevent heart disease or cancer, and recommends against beta-carotene and vitamin E for that purpose.
Evidence-ranked options
| Supplement | Evidence | Typical dose | Notes |
|---|---|---|---|
| Vitamin D (little sun) | A | 600–2,000 IU | Common deficiency. |
| Vitamin B12 (vegans, 50+) | A | From supplements or fortified foods | Essential for these groups. |
| Folic acid (planning pregnancy) | A | 400 mcg a day | Prevents neural tube defects. |
| Iron (if deficient) | A | As advised | Don't take without a need. |
| Multivitamin for disease prevention | D | Optional | No proven heart or cancer prevention. |
| Beta-carotene, vitamin E (prevention) | D | Avoid for this purpose | USPSTF recommends against; beta-carotene raised lung cancer risk in smokers. |
A: strong · B: moderate · C: limited or mixed · D: good evidence of no benefit. See the evidence database.
Build your list
- Take the supplement quiz and the deficiency risk check.
- Check doses and upper limits in the dose calculator.
- Check combinations in the interaction checker.
Frequently asked questions
Is it worth taking a daily multivitamin?
It can cover small gaps, especially with a restricted diet, but won't make up for a poor diet or prevent chronic disease.
Can you take too many vitamins?
Yes. Vitamins A and D, iron and some minerals can build up to harmful levels. Use our dose calculator to check upper limits.
Sources
Educational content, not medical advice. Read our medical disclaimer.