Magnesium supplements and blood pressure in 38 trials
What it found
In 38 randomised trials in people, magnesium supplements lowered systolic blood pressure by 2.81 mm Hg and diastolic blood pressure by 2.05 mm Hg on average.
The authors say the effect was modest and the studies varied a lot.
What they found
Studies in people
Overall blood pressure change
Across all 38 trials, magnesium supplements lowered systolic blood pressure by 2.81 mm Hg and diastolic blood pressure by 2.05 mm Hg compared with placebo. The authors describe this as a modest effect.
People with hypertension
In 17 trials of people with hypertension, magnesium lowered systolic blood pressure by 2.96 mm Hg and diastolic blood pressure by 2.10 mm Hg. In 8 trials of people with normal blood pressure, no significant reductions were seen.
On blood pressure medication
Among people with hypertension who were taking blood pressure-lowering medication, magnesium lowered systolic blood pressure by 7.68 mm Hg and diastolic by 2.96 mm Hg. In untreated hypertensive people, systolic blood pressure did not change significantly, though diastolic fell by 1.88 mm Hg.
Low magnesium levels
In people with hypomagnesemia, magnesium lowered systolic blood pressure by 5.97 mm Hg and diastolic by 4.75 mm Hg. No significant changes were seen in people with normal magnesium levels.
No dose-response link
The analysis found no relationship between the magnesium dose and the size of the blood pressure change. The change stayed about the same across the doses studied.
Supplement type
Trials using magnesium chloride showed larger reductions, and magnesium aspartate hydrochloride lowered diastolic blood pressure. The authors caution these results come from small numbers of studies and may be affected by other factors.
What the authors conclude
“Our findings support the beneficial effect of magnesium on reducing BP among populations with hypertension and hypomagnesemia, although effects should be interpreted with caution due to high heterogeneity of studies.”
Also in their conclusions
- They say their findings support a beneficial effect of magnesium on reducing blood pressure among people with hypertension and hypomagnesemia, though effects should be interpreted with caution due to high heterogeneity of studies.
- They call for larger, well-designed studies assessing higher magnesium doses to refine the dose-response relationship and identify potential optimal supplementation strategies for subpopulations.
How it was done
Reports on whether magnesium intake affects blood pressure have been inconsistent across people with and without high blood pressure. The authors wanted to pool the evidence and look at how dose relates to any change.
They pooled 38 randomised controlled trials with 2709 adults, comparing magnesium supplements with placebo for at least 4 weeks. Elemental magnesium doses ranged from 82.3 mg to 637 mg, with a median dose of 365 mg and a median intervention period of 12 weeks.
What it can’t tell you
- The trials varied widely in their design, participants and supplement types, so the pooled result may not reflect any single situation.
- Most studies used doses between 300 and 500 mg, so the effects of higher doses are not known from this paper.
- The studies did not consistently record dietary magnesium intake, so total magnesium intake is unclear.
Who paid
- Conflicts
- A.E. Schutte has received speaker honoraria from Servier, Abbott, Sanofi, AstraZeneca, Medtronic, Omron, and Aktiia and serves on scientific advisory boards for Medtronic, Roche/Alnylam, AstraZeneca, Servier, SiSU Health, and Sky Labs. The other authors report no conflicts.
- Authors work at
- University of New South Wales, A.E.S.; The George Institute for Global Health, A.E.S.; Harvard T H Chan School of Public Health, Boston (B.B.)
The paper
- Title
- Magnesium Supplementation and Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
- Type
- Systematic review and meta-analysisThe authors follow a set, published method to find every relevant study, then combine the numbers from them into one result.
- Evidence
- Studies in people
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Argeros Z, Xu X, Bhandari B, Harris K, Touyz RM, Schutte AE (2025). Magnesium Supplementation and Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Hypertension (Dallas, Tex.. doi:10.1161/HYPERTENSIONAHA.125.25129Free full textPubMed 41000008DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error