Randomized trial finds multivitamins linked to lower blood pressure in older adults — Evidence Review
Published in American Journal of Hypertension, by researchers from Mass General Brigham
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Table of Contents
Daily multivitamin use may help lower blood pressure and reduce hypertension risk among older adults with poor diet quality, but no overall benefit was seen in the general population. Most related studies find little or no effect of multivitamins on blood pressure or cardiovascular outcomes, though some suggest potential benefit in subgroups with poor baseline nutrition or chronic disease, as highlighted by the original source.
- While most large randomized controlled trials and meta-analyses indicate that multivitamin supplementation does not reduce hypertension risk or cardiovascular events in the general population, small but significant benefits have been observed among individuals with poor dietary intake, chronic illness, or specific nutrient deficiencies 1 2 4 5.
- Some research suggests that individual vitamins, such as B vitamins or vitamin D, may lower blood pressure in deficient or hypertensive individuals, but the effects of multivitamin formulations are generally modest and inconsistent across studies 2 5 7.
- The new findings support a personalized approach, indicating that daily multivitamin use may be more effective for blood pressure control in nutritionally vulnerable subgroups rather than as a universal strategy for all older adults 2 13.
Study Overview and Key Findings
Hypertension is a leading risk factor for cardiovascular disease, particularly among older adults. While multivitamin supplements are commonly used for general health maintenance, their effectiveness in preventing hypertension or lowering blood pressure remains uncertain. This new study from Mass General Brigham addresses this gap by examining whether daily multivitamin use reduces blood pressure or hypertension risk, with a focus on the influence of baseline diet quality. The study leverages data from a large, rigorously designed randomized controlled trial, providing a nuanced look at potential subgroup benefits.
| Property | Value |
|---|---|
| Organization | Mass General Brigham |
| Journal Name | American Journal of Hypertension |
| Authors | Rikuta Hamaya, Howard Sesso, Sidong Li, Jessica Lau, Pamela M. Rist, JoAnn E. Manson, Susanne Rautiainen, Bernhard Haring, Simin Liu, Aladdin H. Shadyab, Lisa Warsinger Martin, Sylvia Wassertheil-Smoller |
| Population | Older adults without hypertension at baseline |
| Sample Size | n=8905, 529, 994 |
| Methods | Randomized Controlled Trial (RCT) |
| Outcome | Blood pressure, risk of hypertension |
| Results | Multivitamins linked to lower BP in older adults with poorer diets. |
Literature Review: Related Studies
To contextualize these results, we searched the Consensus paper database, which includes over 200 million research papers, using the following queries:
- multivitamins blood pressure older adults
- diet quality multivitamins hypertension effects
- daily multivitamin cardiovascular health outcomes
The following table summarizes key findings from related studies, grouped by major research topics:
| Topic | Key Findings |
|---|---|
| Does daily multivitamin use reduce blood pressure or hypertension risk in older adults? | • Most large RCTs and cohort studies find no significant reduction in hypertension risk or blood pressure with multivitamin use in healthy older adults 1 4 13. • Some subgroup analyses and meta-analyses suggest small reductions in blood pressure among those with chronic disease or poor diet quality, but effects are modest and may not prevent hypertension at the population level 2 5. |
| How does diet quality or baseline nutritional status influence the effects of multivitamins on blood pressure? | • Benefits of multivitamin supplementation on blood pressure are more apparent in individuals with poor diet quality, nutrient deficiencies, or higher baseline risk 2 5 7. • Observational studies show dietary B vitamin intake is associated with lower hypertension risk, particularly among women with low folate intake 7. |
| Are individual micronutrients (e.g., vitamin D, B vitamins) effective for blood pressure control? | • Vitamin D supplementation may slightly lower blood pressure in hypertensive or deficient elderly individuals, but has no effect in the general population or on major cardiovascular outcomes 3 5 10. • B vitamin intake, particularly vitamin B-6, is associated with reduced hypertension risk, but evidence for supplementation benefit remains limited 7 8. |
| Do multivitamins lower risk of cardiovascular events beyond blood pressure effects? | • Large RCTs and meta-analyses consistently report no reduction in major cardiovascular events, stroke, or CVD mortality with routine multivitamin use in healthy adults 9 12 13. • Some observational studies suggest a modest reduction in myocardial infarction risk among women using multivitamins long-term, especially those with no CVD history 11. |
Does daily multivitamin use reduce blood pressure or hypertension risk in older adults?
The majority of randomized controlled trials and prospective cohort studies have not found a significant association between daily multivitamin use and reduced blood pressure or risk of developing hypertension in healthy older adults. However, modest benefits have sometimes been observed in specific subgroups, such as individuals with pre-existing chronic disease, poor baseline nutrition, or higher risk of hypertension. The new study aligns with this nuanced view, finding no overall effect but reporting small benefits in nutritionally vulnerable subgroups.
- Large randomized controlled trials indicate no significant reduction in hypertension risk from multivitamin use in healthy older populations 1 4 13.
- Meta-analyses report small but statistically significant reductions in systolic and diastolic blood pressure, predominantly in subjects with chronic disease rather than healthy individuals 2.
- Subgroup analyses in both new and related studies highlight the importance of baseline health status in determining potential benefit 2 5.
- The effect size is generally too small to recommend multivitamins as a universal intervention for blood pressure prevention 2.
How does diet quality or baseline nutritional status influence the effects of multivitamins on blood pressure?
Evidence suggests that individuals with lower diet quality, nutrient deficiencies, or higher risk factors may derive greater benefit from multivitamin supplementation with respect to blood pressure. The current study’s observation of benefit primarily among those with poor diet quality supports this targeted approach.
- Meta-analyses show greater blood pressure reductions in those with poor nutrition or existing deficiencies 2 5.
- Subgroup analyses from cohort studies reveal that women with lower fruit and vegetable intake may experience slight CVD risk reduction from multivitamin use, though findings are not consistent across all outcomes 13.
- Observational evidence links higher dietary B vitamin intake to reduced hypertension risk, particularly among women with low folate 7.
- These findings support a precision nutrition approach—supplementation may be most useful for those with inadequate dietary intake 2 5 7.
Are individual micronutrients (e.g., vitamin D, B vitamins) effective for blood pressure control?
Some studies have investigated whether supplementation with individual vitamins, such as vitamin D or B vitamins, can lower blood pressure. The results are mixed: vitamin D may help in individuals with elevated blood pressure or deficiency, but does not affect broader cardiovascular outcomes. Dietary B vitamin intake has been associated with lower hypertension risk in some populations.
- Vitamin D supplementation modestly reduces blood pressure in elderly individuals with hypertension or deficiency, but not in the general population 3 5.
- Large meta-analyses find no reduction in major cardiovascular events or mortality with vitamin D supplementation 10.
- Higher intake of vitamin B-6, especially when combined with adequate folate, is linked to lower hypertension risk in women 7.
- The evidence for supplementation of individual vitamins, outside of deficiency states, remains limited and inconclusive for broad blood pressure control 3 7.
Do multivitamins lower risk of cardiovascular events beyond blood pressure effects?
Despite the popularity of multivitamin use for general cardiovascular health, most large, long-term randomized controlled trials and meta-analyses show no significant reduction in major cardiovascular events, stroke, or cardiovascular mortality.
- The Physicians’ Health Study II and other large trials found no benefit of daily multivitamin use in reducing myocardial infarction, stroke, or CVD mortality over more than a decade of follow-up 9 12 13.
- Some observational studies report a lower risk of myocardial infarction among women without established cardiovascular disease who use multivitamins long-term 11.
- Meta-analyses confirm no improvement in cardiovascular outcomes for the general population, though isolated observational findings suggest possible benefit in select subgroups 12.
- Overall, the evidence does not support the use of multivitamins for primary cardiovascular prevention in healthy adults 9 12 13.
Future Research Questions
While the new study provides important insights into the potential role of multivitamins for blood pressure control in older adults with poor diet quality, several unanswered questions remain. Future research should focus on clarifying the mechanisms of benefit, optimizing candidate selection for supplementation, and exploring effects in diverse populations and age groups.
| Research Question | Relevance |
|---|---|
| How does multivitamin supplementation affect blood pressure in younger or middle-aged adults? | The current study focused on older adults; effects in younger populations remain unclear and could inform primary prevention strategies 1 4. |
| What are the mechanisms by which multivitamin use may lower blood pressure in nutritionally vulnerable individuals? | Understanding biological pathways (e.g., endothelial function, oxidative stress reduction) may help tailor interventions to those most likely to benefit 2 5 7. |
| Which specific nutrient deficiencies predict the greatest response to multivitamin supplementation for blood pressure control? | Identifying key micronutrient gaps (e.g., B vitamins, vitamin D) could improve precision in recommending supplements 5 7. |
| Does long-term multivitamin use reduce the incidence of hypertension and major cardiovascular events in diverse populations with poor diet quality? | Large-scale RCTs in varied demographic and geographic settings are needed to confirm subgroup benefits and generalizability 2 11 13. |
| How do different multivitamin formulations and dosages influence blood pressure and hypertension risk? | The content and dosage of multivitamin supplements may affect outcomes, but most studies have not examined this in detail 2 6 12. |
This evidence-based summary highlights that while daily multivitamin use may not broadly reduce blood pressure or hypertension risk in all older adults, targeted supplementation could benefit individuals with poor diet quality or nutritional vulnerabilities. Future research should further clarify which populations stand to gain the most from such interventions, the underlying biological mechanisms, and the long-term health impact of supplementation strategies.