A new study links greater calcium intake from food to lower risk for prostate cancer. To determine the effects of calcium intake on prostate cancer, researchers studied 269 veterans who were biopsied because of an elevated prostate-specific antigen test or abnormal rectal examination and 237 healthy (i.e., biopsy not recommended) veterans.
When they compared men with positive biopsy results to healthy men, higher total calcium intake was linked with lower prostate cancer risk among black men, but not among white men. When comparing those whose biopsy results tested positive with those who tested negative, they found that increasing calcium intake from food was associated with lower risk of prostate cancer among all races, as was also observed in comparisons with healthy men.
The finding of an inverse association between prostate cancer and calcium from food but not total calcium suggests that calcium intake from supplements may not help reduce prostate cancer risk as users may expect. It also suggests that adequate calcium from food sources alone may be sufficient to reduce prostate cancer risk. The researchers suggest that a level of supplemental calcium that could reduce prostate cancer risk and a level that could increase risk should be identified.
The researchers also examined the relationship between calcium intake and low- versus high-grade cancers (the higher grade cancers, as measured by the Gleason score, are more likely to spread rapidly). They found no association between calcium and low-grade prostate cancer, but an inverse association between high-grade prostate cancer and dietary calcium. This study was supported in part by the Agency for Healthcare Research and Quality (T32 HS00079).
See “Dietary calcium and risk for prostate cancer: A case-control study among U.S. veterans” by Christina D. Williams, Ph.D., Brian M. Whitley, M.D., Catherine Hoyo, Ph.D., and others in Preventing Chronic Disease 9, E39, 2012.