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Head-to-head evidence comparison — which supplement is right for you?
Multivitamin and Probiotics are closely matched across evidence, studies, and safety.
Verdict
Probably helps
8 of 12 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
30 of 39 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Multivitamin and Probiotics have evidence — compare verdict strength side-by-side.
1 serving daily (as directed on label, typically 1-2 tablets/capsules)
With breakfast, With lunch (if GI sensitive)
Capsule or softgel
10-20 billion CFU
With or without food (strain-dependent), Same time daily for consistency
Capsules with multiple strains
3-6 months
4-8 weeks
2-6 weeks
6-12 weeks
2-4 weeks
4-8 weeks
4-8 weeks
First 1-2 weeks
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
The American Journal of Clinical Nutrition (2024) · Meta analysis · n=5765
Multivitamin-mineral supplementation significantly improved global cognition vs placebo (pooled meta-analysis)
Multivitamin Supplementation Improves Memory in Older Adults: A Randomized Clinical Trial
The American Journal of Clinical Nutrition (2023) · Rct · n=3562
Daily multivitamin supplementation for 3 years significantly improved immediate and delayed recall memory
Effects of cocoa extract and a multivitamin on cognitive function: A randomized clinical trial
Alzheimer's & Dementia (2023) · Rct · n=2262
Multivitamin-mineral supplementation (not cocoa extract) drove significant cognitive improvements in COSMOS-Mind
Preventive Effect of Probiotics on Oral Mucositis Induced by Cancer Treatment: A Systematic Review and Meta-Analysis
International journal of molecular sciences (2022) · Meta analysis · n=708
Three trials using Lactobacilli-based probiotics reported that the incidence of oral mucositis in the probiotic group was significantly low (risk ratio [RR] = 0.84, 95% confidence interval [CI] = 0.77−0.93, p = 0.0004).
Probiotics for treating acute infectious diarrhoea
The Cochrane database of systematic reviews (2020) · Meta analysis · n=12127
Effect size was similar in the sensitivity analysis and marked heterogeneity persisted.
Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children
The Cochrane database of systematic reviews (2017) · Meta analysis · n=9955
A complete case analysis (i.e. participants who completed the study) among trials investigating CDAD (31 trials, 8672 participants) suggests that probiotics reduce the risk of CDAD by 60%.
Based on COSMOS trials (n=5765) showing equivalent of 2.0 years cognitive decline prevention. Effects most pronounced in those with cardiovascular disease. Study duration was 3 years. Effectiveness reflects conservative interpretation of memory and global cognition improvements.
Based on meta-analyses showing benefits for IBS and digestive symptoms. Effect sizes varied considerably between studies with low to very low certainty of evidence. Initial GI symptoms common when starting but typically resolve within 1-2 weeks.
AI-estimated from published studies. Interpret as directional guidance.
Both Multivitamin and Probiotics are closely matched — the best choice depends on your specific health goals.
For reduce inflammation, Probiotics has a higher relevance score (95 vs 50).
No known interactions between Multivitamin and Probiotics have been documented in our database. However, always consult a healthcare provider before combining supplements.