Higher Magnesium Intake Is Associated With a Lower Risk of Frailty in Older Adults.

Objectives: Magnesium deficiency is common in older adults and has been associated with reduced muscle functionality and several age-related diseases. Evidence of its relationship with frailty is scarce. We aimed to explore the association of magnesium intake with incident frailty in the Seniors-ENRICA-1 cohort.

Design: Prospective longitudinal cohort study.

Setting and participants: The ENRICA study is a population-based study (N = 13,105) that includes a representative sample of the noninstitutionalized Spanish population aged 18 years and older. For the present analyses, we used data from the community-dwelling participants aged 60 years and older at baseline (n = 2519). After exclusions, we included data from 1900 participants of the Seniors-ENRICA-1 cohort (mean age 68.7 ± 6.4 years; 51.7% women).

Methods: Food consumption was assessed at baseline with a validated, computer-based, face-to-face dietary history (DH-ENRICA), from which magnesium intake was estimated. Frailty was defined as having 3 or more of Fried criteria: exhaustion, low physical activity, slow gait speed, weakness, and weight loss. Analyses were performed with logistic regression adjusted for potential confounders.

Results: During a mean follow-up of 3.5 years, 136 new cases (7.2%) of frailty occurred. Compared with the lowest sex-specific quartile of magnesium intake, the fully adjusted odds ratio (95% CI) for incident frailty across increasing quartiles of intake was 0.62 (0.36, 1.07), 0.53 (0.28, 0.98), and 0.43 (0.21, 0.86), respectively (P-trend = .016). Corresponding results for slow gait speed were 0.68 (0.47, 1.01), 0.58 (0.37, 0.89), and 0.52 (0.32-0.84), respectively (P-trend = .008). Other Fried criteria showed a similar tendency to reduced frailty incidence with increasing magnesium intake, without achieving statistical significance in the fully adjusted model.

Conclusions and implications: Higher magnesium intake was inversely and independently associated with lower frailty risk, especially of slow gait speed, in community-dwelling older adults, suggesting that adequate intake of this vital ion could help prevent unhealthy aging.