The results pose somewhat of a "conundrum," Ingles said. Although calcium appears to increase risk for prostate cancer, it is essential for bone health and appears to protect against colorectal cancer, she said.
But African-Americans generally have strong and healthy bones and regular screening can help catch colorectal cancer, said first author Glovioell W. Rowland, Ph.D., a post-doctoral fellow in the Keck School's Department of Preventive Medicine.
"It may be possible in the future to personalize treatment by genotype," Rowland said. "But, first, our results have to be confirmed by studies of different races to indicate whether it's the allele that causes the disease or something else that's highly associated with African-American men."
Co-author Gary G. Schwartz, Ph.D., associate professor of cancer biology and epidemiology and prevention at Wake Forest Baptist, said the findings provide some clarity about the link between calcium and prostate cancer. Unlike age and race, which are fixed risk factors for prostate cancer, diet is modifiable.
"We now have a better understanding of why calcium in diet may increase the risk for prostate cancer and who is at increased risk," Schwartz said. "If our results are confirmed, it gives much better insight into the preventable causes of prostate cancer. So if I know I'm a good absorber of calcium, I may want to be careful about the use of calcium supplements."
|Contact: Alison Trinidad|
University of Southern California