Older men and women who consume up to 1,348 mg/day of calcium from food decreased their risk for fracture, nonfatal cardiovascular disease, stroke and all-cause death vs. adults in the lowest quartile of calcium intake, according to research in the Journal of Bone and Mineral Research.
In a population-based, prospective cohort study analyzing the associations between dietary calcium intake and fractures, CVD and all-cause death, researchers found that adults without a history of hypertension in the highest quartile of calcium intake further decreased their risk for stroke, in particular.
“Calcium intake was inversely associated with the mortality rate from all causes and risk of incident fracture and nonfatal CVD, specifically stroke,” the researchers wrote. “We did not find any indication that higher dietary calcium intake could be harmful to health.”
Belal Khan, a PhD student at the NorthWest Academic Center at the University of Melbourne in Australia, and colleagues analyzed data from 34,468 adults aged 40 to 69 years at baseline (between 1990 and 1994) participating in the Melbourne Collaborative Cohort Study. The cohort (20,776 women; mean age, 55 years) was followed for a mean of 13.3 years.
Participants completed a food frequency questionnaire to assess diet in the 12 months preceding baseline; calcium supplementation was assessed as use weekly. Participants completed in-person interviews with researchers between 2003 and 2007 to report incidents of fracture or CVD. Adults with a history of angina, myocardial infarction, stroke, diabetes or cancer at baseline were excluded from the study.
Researchers used Cox regression analysis to estimate HRs in relation to calcium intake for all-cause mortality, CV mortality, MI and cerebrovascular disease.
During 13.3 years, 2,855 deaths occurred; 557 were CVD-related and 1,787 were from cancer.
Researchers found the mortality rate was inversely associated with calcium intake; the HR for the highest vs. the lowest intake quartile was 0.86 (95% CI, 0.76-0.98). Researchers observed similar, but nonsignificant, trends for CVD, MI and cerebrovascular disease.
For CVD, OR for the highest vs. lowest quartile was 0.84 (95% CI, 0.7-0.99); OR for stroke was 0.69 (95% CI, 0.51-0.93). For participants without a history of hypertension, OR was 0.49 (95% CI, 0.34-0.73).
“For participants without a history of hypertension, a higher dietary calcium intake was associated with a 51% decreased risk of stroke, suggesting that higher dietary calcium intake is more likely to be beneficial in populations without pre-existing hypertension, though the effect of hypertension in modifying the association between calcium intake and CVD requires further study,” the researchers wrote.
Researchers also found that fracture risk was inversely associated with calcium intake; the OR for the highest vs. lowest intake quartile was 0.7 (95% CI, 0.54-0.92). Adjustment for country of birth, sex, history of hypertension, smoking status, dietary protein, fat, sodium and phosphorus intake did not change the association. – by Regina Schaffer
Disclosure: The researchers report no relevant financial disclosures.