Two large review studies, including that of the US Preventive Services Task Force from 2022, found no demonstrable benefit of multivitamins for cardiovascular disease, cancer, or life expectancy in healthy adults. A 2024 meta-analysis saw a modest, uncertain signal for cognition, but this is insufficient to act on. Targeted supplementation for confirmed deficiencies or specific circumstances is worthwhile.
A daily multivitamin as a form of health insurance sounds sensible, but two large, carefully conducted review studies -- including one by the US Preventive Services Task Force in 2022 -- found no measurable benefit for cardiovascular disease, cancer or life expectancy in healthy adults who eat reasonably well. So the money is not in the pill.
The one small bright spot is cognition: a 2024 meta-analysis saw a modest, uncertain signal that multivitamins may do something for memory and thinking ability, but that evidence is still too preliminary to act on. Safety is not a good reason to take one anyway: standard multivitamins are indeed perfectly safe, but that does not automatically apply to high-dose varieties. Too much vitamin A or iron is harmful, so 'extra strength' is not a selling point.
One exception genuinely matters: if you have a confirmed deficiency, follow a vegan diet (B12), are pregnant (folic acid), or get little sun and have low vitamin D, supplementing is worthwhile. In that case it is about a targeted approach, not an all-in-one pill. If you want to know whether you are deficient in anything, a blood test -- through your GP or a commercial lab -- can make that clear fairly quickly.
Moderate evidence, 3 source(s); the direction is probable but not firmly proven.