Magnesium Citrate for Heart Health? What the Research Says

observational-study PMID: 35253448

Quick Summary: A recent study looked at whether magnesium citrate could help improve artery health and blood pressure. The results showed that taking magnesium citrate for 6 months didn't significantly change artery stiffness or blood pressure in the people studied.

Does Magnesium Citrate Help Arteries?

This research aimed to see if magnesium citrate could help with arterial stiffness, which is a measure of how flexible your arteries are. Stiff arteries can increase the risk of heart problems. The study also looked at blood pressure.

The study found:

Magnesium citrate did not significantly improve artery stiffness.

Magnesium citrate did not lower blood pressure.

Magnesium citrate did increase magnesium levels in the blood and urine.

Study Details

Who was studied: 164 adults who were overweight or slightly obese.

How long: The study lasted for 6 months (24 weeks).

What they took: Participants took either magnesium citrate, magnesium oxide, magnesium sulfate, or a placebo (a sugar pill). The dose of magnesium was 450mg per day.

What This Means For You

If you're overweight or obese, this study suggests that taking magnesium citrate won't likely improve your artery health or blood pressure.

The study doesn't mean magnesium is useless. It just means that magnesium citrate may not be the best choice for improving artery health in this specific group of people.

If you're concerned about your heart health, talk to your doctor about the best ways to manage your risk factors.

Study Limitations

The study only looked at overweight and obese adults, so the results might not apply to everyone.

The study lasted only 6 months. Longer studies might show different results.

The people in the study had normal magnesium levels at the start. The results might be different for people who are low in magnesium.

The study compared different forms of magnesium. It's possible that some forms are absorbed or used by the body differently.

Key Findings

Magnesium citrate (450 mg/day) did not significantly reduce arterial stiffness (measured via carotid-to-femoral pulse wave velocity [cfPWV]) or blood pressure in overweight/obese adults over 24 weeks. Other formulations (magnesium oxide, sulfate) also showed no effects. However, magnesium citrate increased plasma magnesium (+0.04 mmol/L; 95% CI +0.02 to +0.06) and 24-hour urinary magnesium excretion (+3.12 mmol; 95% CI +2.23 to +4.01) compared to placebo. Urinary excretion was significantly higher with citrate than with oxide or sulfate.

Study Design

This was a randomized, double-blind, placebo-controlled trial (RCT) with 164 participants (mean age 63.2±6.8 years; 63.4% women) categorized as overweight or slightly obese. The 24-week intervention compared three magnesium formulations (citrate, oxide, sulfate) and placebo. Primary outcome: cfPWV (gold standard for arterial stiffness). Secondary outcomes: blood pressure, plasma/urine magnesium. Analyses followed intention-to-treat principles.

Dosage & Administration

Participants received 450 mg/day of elemental magnesium (equivalent to 1875 mg magnesium citrate, 900 mg magnesium oxide, or 1125 mg magnesium sulfate) in three divided doses with meals. Placebo matched the appearance of supplements.

Results & Efficacy

Arterial stiffness (cfPWV): No significant change vs placebo (mean difference: -0.17 m/s; 95% CI -0.50 to +0.16; p = nonsignificant).
Blood pressure: No significant differences observed for systolic or diastolic measures.
Magnesium levels:
Plasma: Citrate increased by +0.04 mmol/L (95% CI +0.02 to +0.06).
Urine: Citrate increased excretion by +3.12 mmol/24h (95% CI +2.23 to +4.01), with greater excretion vs oxide/sulfate (p < 0.05).
Comparisons: All formulations similarly failed to improve cfPWV or BP.

Limitations

Population specificity: Results limited to overweight/obese adults; may not apply to younger, leaner, or clinical populations.
Duration: 24 weeks may be insufficient to detect long-term effects on vascular health.
Baseline magnesium: Participants had normal magnesium levels; effects in deficient individuals remain unclear.
Formulation equivalence: Doses were equated by elemental magnesium, but differences in bioavailability or metabolism may exist.
Single adverse event: Safety data limited due to low event reporting.

Clinical Relevance

For overweight/obese adults, magnesium citrate (450 mg/day) does not improve arterial stiffness or blood pressure over 24 weeks. However, it effectively raises plasma and urinary magnesium, suggesting better bioavailability vs oxide/sulfate. Clinicians should not recommend magnesium supplementation for vascular health in this population based on these results. Future studies in magnesium-deficient individuals or with longer follow-up are needed.

Source: https://pubmed.ncbi.nlm.nih.gov/35253448/ (RCT: NCT03632590).