Friday, September 16, 2011
A study by epidemiologists suggests that a high intake of calcium causes prostate cancer among African-American men who are genetically good absorbers of the mineral
High dietary intake of calcium has long been linked to prostate cancer. The study is one of the few to explore genes related to calcium absorption or to examine diet in a large African-American population. Although prostate cancer is 36% more common among African-Americans than in non-Hispanic whites, data on the diet-cancer link primarily comes from Caucasian populations. The team targeted a genetic allele that is more common in populations of African origin than in other populations and which is associated with regulating the absorption of calcium. The study found that men who reported the highest intake of calcium were two times more likely to have localized and advanced prostate cancer than those who reported the lowest. Men with a genotype associated with poor calcium absorption were 59% less likely to have been diagnosed with advanced prostate cancer than men who genetically were the best absorbers of calcium. And, among men with calcium intake below the median, genetically poor absorbers had a 50% decreased risk of having advanced prostate cancer than the best absorbers. Although calcium appears to increase risk for prostate cancer, it is essential for bone health and appears to protect against colorectal cancer.