Higher Calcium Intake Linked to Reduced Colorectal Cancer Risk

Higher calcium intake is associated with a reduced risk of colorectal cancer (CRC), according to a cohort study published in JAMA Network Open analyzing data from the National Institutes of Health–AARP Diet and Health Study.

The findings suggest a consistent inverse relationship between calcium intake and CRC incidence across different sources of calcium and tumor sites.

The study included 471,396 participants aged 50 to 71 years at baseline who were followed for a median of 18.4 years. Over 7.3 million person-years of follow-up, 10,618 first primary CRC cases were identified. Researchers found that participants in the highest quintile of total calcium intake had a significantly lower risk of CRC compared with those in the lowest quintile (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.65-0.78; P < .001 for trend). The association was consistent regardless of calcium source—whether from dairy, nondairy foods, or supplements—and across different tumor sites.

“Higher total calcium intake was associated with a lower risk of CRC, with consistent results across calcium sources and tumor sites,” the study noted. These findings reinforce the potential protective role of calcium against CRC and highlight the importance of adequate dietary calcium intake.

Among non-Hispanic Black participants, the study did not find a statistically significant association between calcium intake and CRC risk (HR, 0.60; 95% CI, 0.32-1.13; P = .12 for trend). However, the researchers did not observe significant differences in the effect of calcium intake on CRC risk across racial and ethnic groups overall.

“Increasing calcium intake, especially among groups with lower consumption, may be associated with reductions in avoidable differences in CRC risk,” the study concluded. These results suggest a potential role for dietary interventions in CRC prevention, particularly for populations with low calcium intake.

Reference
Zouiouich S, Wahl D, Liao LM, Hong HG, Sinha R, Loftfield E. Calcium intake and risk of colorectal cancer in the NIH-AARP diet and health study. JAMA Netw Open. Published online February 3, 2025. doi:10.1001/jamanetworkopen.2024.60283