Lancet Reg Health West Pac

Calcium supplements not linked to dementia risk in older women

October 9, 2025

Study details: This post-hoc analysis of the Perth Longitudinal Study of Aging Women evaluated the long-term cognitive effects of calcium supplementation. Originally designed as a randomized, double-blind, placebo-controlled trial for fracture prevention, the study included 1,460 women aged ≥70 who received either 1,200 mg/day of calcium or placebo for five years. Dementia-related hospitalizations and deaths were tracked over 14.5 years. Outcomes were analyzed using Kaplan–Meier survival curves and Cox regression under both intention-to-treat (ITT) and per-protocol (PP; ≥80% tablet compliance, n=830) frameworks.

Results: Dementia was diagnosed in 269 participants—128 in the calcium group and 141 in the placebo group—showing no statistically significant difference. Calcium supplementation didn’t increase risk of dementia-related events (unadjusted ITT hazard ratio [HR], 0.90; 95% confidence interval [CI], 0.71–1.15), hospitalizations (HR, 0.89; 95% CI, 0.69–1.15), or deaths (HR, 0.78; 95% CI, 0.54–1.13). PP analyses yielded similar results.

Clinical impact: These findings provide reassurance that calcium supplementation, commonly used for osteoporosis prevention, doesn’t increase dementia risk in older women. Clinicians can continue recommending calcium for bone health without concern for adverse cognitive outcomes in this population.

Source:

Ghasemifard, Negar et al. (2025, October 6). Lancet Reg Health West Pac. Calcium supplementation and the risk of dementia in the Perth Longitudinal Study of Aging Women: a post-hoc analysis of a randomised clinical trial for fracture prevention. https://www.thelancet.com/journals/lanwpc/article/PIIS2666-6065(25)00233-0/fulltext