Do daily multivitamins improve health?

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1. 1

   Effect of a multivitamin and cocoa flavanol extract on changes in neurofilament light, N-terminal tau fragment, and oligomeric amyloid-β levels in COSMOS-clinic.

   Journal of Alzheimer's disease : JAD (Rist et al.)Published Sep 23, 2026Checked Oct 4, 2026

   “The primary outcomes of this ancillary study were the 2-year change in neurofilament light chain (NfL), N-terminal tau fragment (NT1), and oligomeric amyloid-β (oAβ) levels. We examined the effect of each intervention on each biomarker in separate general linear models of response profiles.ResultsWe included 506 individuals with available NT1 or NfL levels and 498 individuals with oAβ levels. We observed no significant difference between the changes over time in either NT1 (mean difference in yearly percentage change=3.7%; 95% CI: -3% to 10.8%; p = 0.29), NfL (3.1%; 95% CI: -1.9% to 8.3%; p = 0.23), or oAβ (-8.9%; 95% CI: -23.9% to 9%; p = 0.31) for those randomized to MVM versus placebo. We observed no significant differences between changes over time for those randomized to CE versus placebo for NT1 (-0.7%; 95% CI: -7.1% to 6.1%; p = 0.83), NfL (0.5%; 95% CI: -4.4% to 5.6%; p = 0.85), or oAβ (-5.9%; 95% CI: -21.4% to 12.6%; p = 0.51).ConclusionsDaily supplementation with MVM or CE compared to placebo did not affect two-year changes in NfL, NT1, and oAβ.Clinicaltrials.gov: COSMOS (clinicaltrials.gov NCT02422745).”

2. 2

   Multivitamin supplementation and COVID-19 incidence and symptom severity in the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized trial.

   The American journal of clinical nutrition (Li et al.)Published Jun 9, 2026Checked Oct 4, 2026

   “Of the 18,205 participants who remained in the trial and were adherent to study pills as of 1 January, 2020, 382 were randomly assigned to MVM and 404 to MVM placebo (no MVM) and reported a COVID-19 infection through 31 December, 2020. In intention-to-treat analysis, the hazard ratio for MVM compared with placebo was 0.93 for COVID-19 incidence [95% confidence interval (CI): 0.81, 1.07]. Among the 338 cases with detailed symptom data, the odds ratio for symptomatic COVID-19 comparing MVM with placebo was 0.70 (95% CI: 0.44, 1.11). In per-protocol analyses, among participants compliant with study pills during 2020, the odds ratio for symptomatic COVID-19 was 0.60 (95% CI: 0.37, 0.99).ConclusionsA daily MVM supplement, compared with placebo, does not significantly reduce COVID-19 incidence among older adults but shows a promising signal lowering the odds of symptomatic COVID-19 illness. The Cocoa Supplement and Multivitamin Outcomes Study was registered at clinicaltrials.gov as NCT02422745.”

3. 3

   Long-Term Effect of Multivitamin Supplementation on Incident Self-Reported Hypertension and Blood Pressure Changes in the COSMOS Trial.

   American journal of hypertension (Hamaya et al.)Published Apr 1, 2026Checked Oct 4, 2026

   “Hypertension diagnosis was ascertained through self-reports. Additionally, in two substudies with BP measurements (N = 529 at clinic by research staff and 994 at home by technician), we evaluated the effects on 2-year BP changes.ResultsIncident hypertension was observed in N = 1034 (22.9%) in MVM arm and N = 1039 (23.6%) in placebo arm over a median of 3.4 years (IQR: 3.0, 3.9) of follow-up, with hazard ratio (HR) 0.98 [95% CI: 0.90, 1.06]. Effects differed according to baseline diet quality, with HRs of incident hypertension 0.81 [0.70, 0.95] and 1.14 [1.01, 1.28] among participants with lower and higher Alternate Mediterranean Diet score, respectively (P-interaction = .001). There was no effect of MVM on 2-year changes in systolic BP (4.4 mmHg in MVM; 4.5 mmHg in placebo), while pronounced effects were observed for baseline normal BP (P-interaction = .004).ConclusionsMVM supplementation versus placebo did not reduce hypertension incidence or lower BP overall. Exploratory analyses showed greater reduction in hypertension risk and BP changes among those with lower dietary quality and normal BP at baseline, respectively.Clinical trial registrationNCT02422745.”

4. 4

   Multivitamins in Adult Medical Practice: Evidence, Risks, and Pragmatic Prescribing.

   Cureus (Neves et al.)Published Jan 21, 2026Checked Oct 4, 2026

   “This is not a systematic review. Multivitamins are justified for documented deficiencies or high-risk states, including malabsorption, post-bariatric surgery, chronic alcohol use, pregnancy/lactation, and frailty. In generally nourished adults, multivitamins do not reduce cardiovascular events or mortality, and evidence for cancer prevention is marginal without a mortality impact. Recent data suggest small cognitive benefits in older adults. Risks include hypervitaminosis A/D/E, clinically relevant drug-nutrient interactions, masking of specific deficiencies, behavioral displacement of diet-first strategies, and unnecessary cost. Outside of deficiency or clearly increased need, routine multivitamin prescribing provides little clinical gain and exposes patients to avoidable harms. Internists should screen, test, and treat specifically, prefer targeted nutrients, monitor safety, and educate patients against overreliance on supplements.”

5. 5

   A to Z of Health: An Evidence-Based Narrative Review of Multivitamin-Multimineral and Nutraceutical Supplementation.

   Cureus (Nawathe et al.)Published Apr 30, 2026Checked Oct 4, 2026

   “The review included details from various clinical studies, including randomized controlled trials, meta-analyses, and cohort studies on MVM supplementation, with special emphasis on cardiovascular, endocrine (especially diabetic mellitus), cancer, cognitive, skeletal, immune, and ocular health outcomes. It also highlights evidence in special populations such as pregnant and lactating women, infants, children, adolescents, older adults, and athletes. Furthermore, evidence related to nutraceuticals such as omega-3 fatty acids, lutein, curcumin, ginseng, brahmi, ashwagandha, and coenzyme Q10 is included. The review covers the safety and toxicity aspects of MVM supplements; however, limited evidence is available on drug-nutrient interactions. Overall, MVM supplements, along with nutraceuticals, may play a valuable role in targeted health optimization, especially in populations at risk of deficiencies. Standardized formulations, long-term safety evaluation, and integration of personalized nutrition approaches are critical to enhancing their clinical and public health impact.”

6. 6

   Consumer-Relevant Endpoints in Nutritional Supplement Research: A Case of Multivitamin and Mineral Supplements.

   Current developments in nutrition (Sheldon et al.)Published May 2, 2026Checked Oct 4, 2026

   “They are one of only a few interventions the public actively embraces, despite clear guidelines that do not recommend routine MVM use for healthy people, because a balanced diet should provide all essential nutrients. This public adoption of MVMs creates a paradox when people say they take MVMs to support their well-being, yet scientific studies do not capture or measure what that actually entails. It also presents an opportunity to explore why this divergence exists, and in doing so, explore how people understand health and well-being. This review argues that trials of MVM supplementation in the general adult population are methodologically misaligned with the outcome consumers value, relying on endpoints and instruments that are neither representative nor sufficiently sensitive. Beyond any placebo effect, the summative effect of addressing multiple subclinical micronutrient deficiencies represents a potential, plausible biological basis for improved quality of life (QoL). Future MVM studies should be designed to comprehensively evaluate QoL and related outcomes (e.g., cognition, fatigue, and resilience) to align with reasons why adults take MVM supplements.”