The mediating role of oxidative balance score in the association between magnesium-rich diet and cardiovascular mortality: Findings from the PLCO cohort study.

BACKGROUND AND AIMS: A magnesium-rich diet (MRD), a novel dietary pattern emphasizing the synergistic benefits of magnesium-dense foods, has been linked to reduced risk of cardiovascular diseases (CVD). However, its association with CVD mortality remains uncertain. This study aimed to examine the relationship between MRD and CVD-related mortality.

METHODS

A total of 91,891 adults were enrolled from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Dietary intake was assessed using a validated food frequency questionnaire, and MRD scores were derived from consumption of whole grains, nuts, vegetables, fruits, legumes, coffee, and tea to evaluate adherence to the dietary pattern. Cox proportional hazards regression was applied to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs). During a median follow-up of 15.0 years, 5848 CVD deaths were recorded, comprising 4236 from heart disease and 1213 from cerebrovascular disease.

RESULTS

In the multivariable-adjusted model, individuals in the highest MRD quartile had significantly lower risks of death from overall CVD (adjusted HR: 0.74, 95 % CI: 0.68, 0.81), heart disease (adjusted HR: 0.74, 95 % CI:0.67, 0.82), and cerebrovascular disease (adjusted HR: 0.67, 95 % CI:0.56, 0.81), compared with those in the lowest quartile. Dose-response analyses indicated a linear inverse relationship between MRD and mortality from CVD, heart disease, and cerebrovascular disease. Subgroup analyses revealed a more pronounced protective association in heavy drinkers relative to non-drinkers, light drinkers, or moderate drinkers. Notably, the oxidative balance score (OBS) mediated 18.53 % of the association between MRD and CVD mortality.

CONCLUSIONS

High adherence to MRD was associated with a substantially reduced risk of CVD mortality, including both heart disease and cerebrovascular disease, with oxidative balance playing a potential mediating role.