Effect of Magnesium Supplementation on Inflammatory Parameters: A Meta-Analysis of Randomized Controlled Trials

This was a meta-analysis of randomized controlled trials in adults. Most participants had metabolic disorders such as diabetes, pre-diabetes, or overweight/obesity; a smaller number of trials included pregnant individuals and participants with cardiovascular or respiratory conditions. Studies were conducted in Asia, North or South America, and Europe.

Oral magnesium, primarily magnesium oxide 250 mg/day, was compared with placebo. Across the included randomized trials, follow-up ranged from 4 to 26 weeks, with a median duration of 12 weeks.

Magnesium supplementation produced a modest but statistically significant reduction in serum C-reactive protein and increased nitric oxide compared with placebo. For CRP, the pooled analysis included 737 participants across 15 RCTs and showed SMD = −0.356 (95% CI: −0.659 to −0.054; p = 0.02). For nitric oxide, the effect was SMD = 0.321 (95% CI: 0.037 to 0.604; p = 0.026) based on 3 studies with 194 participants, with I2 = 0%. Effects on IL-6, total antioxidant capacity, glutathione, and TNF-α were not significant, and malondialdehyde was only borderline significant (SMD = −0.604; 95% CI: −1.224 to 0.017; p = 0.057).

Heterogeneity was substantial across outcomes, and several biomarkers were supported by few studies, limiting certainty. The included trials were relatively short and mostly involved metabolic populations, which reduces generalizability. Effects were inconsistent across inflammatory markers, and some findings were only borderline significant.