What does the research show about multivitamin?

Multivitamin

Large trials found daily multivitamins did not change cardiovascular events or death. A US Preventive Services Task Force review found a small drop in cancer incidence, while one of two large trials found none. Three trials within one study found small memory gains in older adults. Beta carotene raised lung cancer risk in smokers.

Add to Bio HackChecked 2026-11-09

Status: Dietary supplement in the US.
Also called: multivitamin-multimineral, MVM, multi, daily vitamin, Centrum, Centrum Silver, one-a-day, prenatal vitamin
Taken for: general health, filling nutrient gaps, energy, immunity, cancer prevention, heart health, longevity, memory, healthy aging

Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on

Shown to help1

ModerateShown to improve global cognition and memory slightly over 3 years in US adults 60 and older, all in one trial of one product.

Reported risks2

ModerateShown to raise lung cancer in current smokers at high beta carotene doses of 20 to 30 mg a day, well above typical multivitamin content.How often is not known
LimitedLimited evidence: single supplements were linked to hip fracture with vitamin A, hemorrhagic stroke with vitamin E, and kidney stones with vitamin C and calcium.How often is not known

What people take it for, and what was found

Shown to help1

Moderate

Memory and cognition in older adults

Shown to improve global cognition and memory slightly over 3 years in US adults 60 and older, all in one trial of one product.

The numbers and sources

Effect: In COSMOS-Mind (2,262 adults, mean age 73), a daily multivitamin improved a global cognition composite over 3 years (mean z 0.07, 95% CI 0.02 to 0.12) [7]. In COSMOS-Web (3,562 adults), immediate recall was better at 1 year and across 3 years, and secondary outcomes did not change [8]. Pooling three COSMOS substudies, global cognition improved by 0.07 SD units (95% CI 0.03 to 0.11) and episodic memory by 0.06 SD units (95% CI 0.03 to 0.10), which the authors equate to about 2 years of cognitive aging [9].
Population: US adults aged 60 and older in the COSMOS trial [7][8][9].
Sources: [7], [8], [9]
Caveats: All three come from one parent trial and one product. COSMOS-Web gave Centrum Silver [8]. Funder lists in Europe PMC include Pfizer [9] and BASF [8]. Participants were 89% non-Hispanic White in COSMOS-Mind [7].

Mixed results3

Moderate

Cancer

Mixed results: one trial and pooled trials found slightly less total cancer, while another trial found no change. Two trials found less lung cancer.

The numbers and sources

Effect: Pooling 4 RCTs (48,859 people), multivitamins were associated with lower cancer incidence (OR 0.93, 95% CI 0.87 to 0.99) and lung cancer (OR 0.75, 95% CI 0.58 to 0.95, 2 RCTs) [4]. In the Physicians' Health Study II, total cancer fell from 18.3 to 17.0 per 1,000 person-years (HR 0.92, 95% CI 0.86 to 0.998), with no change in prostate or colorectal cancer [5]. In COSMOS, invasive cancer did not differ (HR 0.97, 95% CI 0.86 to 1.09), and lung cancer was lower (HR 0.62, 95% CI 0.42 to 0.92) [2].
Population: Healthy adults without known deficiency [4]; male physicians over 11.2 years [5]; older US adults over 3.6 years [2].
Sources: [2], [4], [5]
Caveats: The trials disagree on total cancer. Absolute risk differences in the adequately powered trials ranged from -0.2% to -1.2% [4]. The Task Force review noted important limitations in the multivitamin evidence [4].

Limited

Biological aging markers

One trial found slower change in two of five DNA methylation clocks over 2 years. The authors state the clinical relevance is not known.

The numbers and sources

Effect: Over 2 years, a daily multivitamin slowed yearly change in two DNA methylation clocks against placebo, by 0.113 years for PCGrimAge (95% CI -0.205 to -0.020) and 0.214 years for PCPhenoAge (95% CI -0.410 to -0.019). The effect on PCGrimAge was larger in people with faster biological aging at baseline [12].
Population: 958 COSMOS participants (482 women, 476 men) [12].
Sources: [12]
Caveats: Five clocks were tested and two changed. The authors state that the clinical relevance of these changes is not known [12].

Limited

Nutrient levels in blood

One trial found higher blood carotenoids and alpha-tocopherol over 2 years in older adults, while a 4-week trial in vitamin deficiency found no rise.

The numbers and sources

Effect: Over 2 years, Centrum Silver raised serum total carotenoids by 15.5%, beta carotene by 46.96% and alpha-tocopherol by 29.50% against placebo. Lycopene, beta-cryptoxanthin, zeaxanthin and alpha-carotene did not change [13]. In 155 adults with low vitamin A, D or E, 4 weeks of a multivitamin plus nutrition education did not raise blood levels or lower deficiency rates more than nutrition education plus placebo [14].
Population: 399 older US adults in a COSMOS biospecimen substudy [13]; 155 adults aged 18 to 65 with fat-soluble vitamin deficiency [14].
Sources: [13], [14]
Caveats: Blood levels are a marker, not a health outcome. The deficiency trial lasted 4 weeks [14].

Not shown to help4

Moderate

Cardiovascular disease

Not shown to lower heart attack, stroke or cardiovascular death in older US adults over 3.6 to 11 years.

The numbers and sources

Effect: In the Physicians' Health Study II, a daily multivitamin for a median 11.2 years did not change major cardiovascular events (HR 1.01, 95% CI 0.91 to 1.10), myocardial infarction (HR 0.93), stroke (HR 1.06) or cardiovascular death (HR 0.95) [1]. In COSMOS, the composite cardiovascular outcome did not differ (HR 0.98, 95% CI 0.86 to 1.12) over a median 3.6 years [2]. Among 8,905 COSMOS participants without hypertension, new self-reported hypertension occurred in 22.9% on the multivitamin and 23.6% on placebo (HR 0.98, 95% CI 0.90 to 1.06), and 2-year systolic pressure change did not differ [3].
Population: 14,641 US male physicians aged 50 and older [1]; 21,442 US women aged 65 and older and men aged 60 and older [2][3].
Sources: [1], [2], [4], [3]
Caveats: The US Preventive Services Task Force evidence review covered these trials and found little or no benefit for cardiovascular disease from vitamin and mineral supplements [4].

Moderate

Death from any cause

Not shown to lower death from any cause in two large trials of older adults. In three US cohorts, daily users had about 4% higher mortality early in follow-up.

The numbers and sources

Effect: All-cause mortality did not change in the Physicians' Health Study II (HR 0.94, 95% CI 0.88 to 1.02) [1] or COSMOS (HR 0.93, 95% CI 0.81 to 1.08) [2]. In 390,124 adults from 3 US cohorts followed up to 27 years, daily multivitamin users had slightly higher mortality than nonusers in the first half of follow-up (HR 1.04, 95% CI 1.02 to 1.07), and the second half gave the same estimate with an interval that includes no difference (HR 1.04, 95% CI 0.99 to 1.08) [6].
Population: Trial participants [1][2]; adults without chronic disease at baseline in NIH-AARP, PLCO and the Agricultural Health Study [6].
Sources: [1], [2], [6]
Caveats: The cohort data are observational, and a 4% difference is within the reach of confounding. Daily users were more often female and college educated and less often current smokers [6]. The cohort's authors state their conclusion as no mortality benefit [6].

Limited

Fractures

One trial found no drop in total, hip or nonvertebral fractures over 3.6 years in older US adults.

The numbers and sources

Effect: In COSMOS, Centrum Silver for a median 3.6 years did not lower total clinical fractures (aHR 1.09, 95% CI 1.00 to 1.19), hip fractures (aHR 1.06, 95% CI 0.80 to 1.42) or nonvertebral fractures (aHR 1.10, 95% CI 1.00 to 1.20) against placebo. 2,083 fractures occurred in all [10].
Population: 21,442 US women aged 65 and older and men aged 60 and older, not selected for osteoporosis [10].
Sources: [10]
Caveats: Fractures were self-reported. An ancillary analysis of a trial designed for cancer and cardiovascular outcomes.
Why limited: This rests on one trial, of 21,442 people. Strength counts independent studies that agree, so one trial is limited at any size.

Limited

Immunity and COVID-19

One trial found no difference in COVID-19 cases or symptomatic illness against placebo in older US adults, in a secondary analysis.

The numbers and sources

Effect: In the final COSMOS year (2020), COVID-19 incidence did not differ between multivitamin and placebo (HR 0.93, 95% CI 0.81 to 1.07). Among 338 cases with symptom data, symptomatic illness did not differ significantly (OR 0.70, 95% CI 0.44 to 1.11). In the per-protocol analysis, the odds ratio was 0.60 (95% CI 0.37 to 0.99) [11].
Population: 18,205 adherent COSMOS participants as of January 2020 [11].
Sources: [11]
Caveats: A secondary analysis with self-reported infections. The per-protocol result is secondary.
Why limited: This rests on one trial, of 21,442 people. Strength counts independent studies that agree, so one trial is limited at any size.

Doses studied

The large trials gave one standard daily multivitamin tablet [1][2][5]. COSMOS-Web used Centrum Silver [8]. Beta carotene trials in smokers used 20 to 30 mg a day, while 47 common multivitamins contained a median 0.3 mg a day (range 0 to 17.2 mg) and vision-marketed formulas a median 3 mg a day [15].

Risks

Reported risks2

ModerateHow often is not known

Beta carotene and lung cancer in smokers

Shown to raise lung cancer in current smokers at high beta carotene doses of 20 to 30 mg a day, well above typical multivitamin content.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: Beta carotene, with or without vitamin A, was associated with more lung cancer (OR 1.20, 95% CI 1.01 to 1.42, 4 RCTs, 94,830 people) and cardiovascular death (OR 1.10, 95% CI 1.02 to 1.19) [4]. Among current smokers, beta carotene raised lung cancer risk (OR 1.24, 95% CI 1.10 to 1.39) and among former smokers did not (OR 1.10, 95% CI 0.84 to 1.45). 70% of 47 sampled multivitamins contained beta carotene [15].
Population: People at high risk of lung cancer in large prevention trials [4][15].
Sources: [4], [15]
Caveats: The trial doses (20 to 30 mg a day) are well above the median multivitamin content of 0.3 mg [15].

LimitedHow often is not known

Single-nutrient harms

Limited evidence: single supplements were linked to hip fracture with vitamin A, hemorrhagic stroke with vitamin E, and kidney stones with vitamin C and calcium.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: The Task Force review found limited evidence linking some single supplements to serious harms: hip fracture with vitamin A, hemorrhagic stroke with vitamin E, and kidney stones with vitamin C and calcium [4].
Population: Healthy adults in RCTs and cohorts [4].
Sources: [4]
Caveats: These are single-nutrient findings, not tests of multivitamins.

Claims tested and not found

That a daily multivitamin prevents heart disease. Major cardiovascular events did not change over 11.2 years in the Physicians' Health Study II [1] or in COSMOS [2].
That a daily multivitamin extends life. All-cause mortality did not differ from placebo in two large trials [1][2].
That a daily multivitamin prevents fractures in older adults. Total, hip and nonvertebral fractures did not fall in COSMOS [10].

Sources

Sesso HD, Christen WG, Bubes V, et al. Multivitamins in the prevention of cardiovascular disease in men: the Physicians' Health Study II randomized controlled trial. JAMA. 2012. https://doi.org/10.1001/jama.2012.14805
Sesso HD, Rist PM, Aragaki AK, et al. Multivitamins in the prevention of cancer and cardiovascular disease: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial. American Journal of Clinical Nutrition. 2022. https://doi.org/10.1093/ajcn/nqac056
Hamaya R, Li S, Lau J, et al. Long-Term Effect of Multivitamin Supplementation on Incident Self-Reported Hypertension and Blood Pressure Changes in the COSMOS Trial. American Journal of Hypertension. 2026. https://doi.org/10.1093/ajh/hpaf224
O'Connor EA, Evans CV, Ivlev I, et al. Vitamin and Mineral Supplements for the Primary Prevention of Cardiovascular Disease and Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA. 2022. https://doi.org/10.1001/jama.2021.15650
Gaziano JM, Sesso HD, Christen WG, et al. Multivitamins in the prevention of cancer in men: the Physicians' Health Study II randomized controlled trial. JAMA. 2012. https://doi.org/10.1001/jama.2012.14641
Loftfield E, O'Connell CP, Abnet CC, et al. Multivitamin Use and Mortality Risk in 3 Prospective US Cohorts. JAMA Network Open. 2024. https://doi.org/10.1001/jamanetworkopen.2024.18729
Baker LD, Manson JE, Rapp SR, et al. Effects of cocoa extract and a multivitamin on cognitive function: A randomized clinical trial. Alzheimer's & Dementia. 2023. https://doi.org/10.1002/alz.12767
Yeung LK, Alschuler DM, Wall M, et al. Multivitamin Supplementation Improves Memory in Older Adults: A Randomized Clinical Trial. American Journal of Clinical Nutrition. 2023. https://doi.org/10.1016/j.ajcnut.2023.05.011
Vyas CM, Manson JE, Sesso HD, et al. Effect of multivitamin-mineral supplementation versus placebo on cognitive function: results from the clinic subcohort of the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial and meta-analysis of 3 cognitive studies within COSMOS. American Journal of Clinical Nutrition. 2024. https://doi.org/10.1016/j.ajcnut.2023.12.011
Crandall CJ, Chou S, Kim E, et al. Effects of cocoa extract supplementation and multivitamin/multimineral supplements on self-reported fractures in the Cocoa Supplement and Multivitamins Outcomes Study randomized clinical trial. Journal of Bone and Mineral Research. 2025. https://doi.org/10.1093/jbmr/zjaf030
Li J, Manson JE, Rist PM, et al. Multivitamin supplementation and COVID-19 incidence and symptom severity in the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized trial. American Journal of Clinical Nutrition. 2026. https://doi.org/10.1016/j.ajcnut.2026.101355
Li S, Hamaya R, Zhu H, et al. Effects of daily multivitamin-multimineral and cocoa extract supplementation on epigenetic aging clocks in the COSMOS randomized clinical trial. Nature Medicine. 2026. https://doi.org/10.1038/s41591-026-04239-3
Christopher CN, Erdman JW, Kim E, et al. Effects of Randomized Multivitamin Supplementation on Carotenoids and α-Tocopherol in the COcoa Supplement and Multivitamin Outcomes Study. Journal of the Academy of Nutrition and Dietetics. 2026. https://doi.org/10.1016/j.jand.2026.156299
Yusupu S, Yang Y, Geng X, et al. Multivitamin supplements are not superior to nutrition education in improving fat-soluble vitamin levels: A double-blind randomized controlled trial. Asia Pacific Journal of Clinical Nutrition. 2026. https://pubmed.ncbi.nlm.nih.gov/41565231/
Tanvetyanon T, Bepler G. Beta-carotene in multivitamins and the possible risk of lung cancer among smokers versus former smokers: a meta-analysis and evaluation of national brands. Cancer. 2008. https://doi.org/10.1002/cncr.23527

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