A new study led by researchers at Memorial University shows that dietary calcium and vitamin D are associated with a lower risk of colorectal cancer. The study was based on the comparison of dietary information between colorectal cancer patients and controls collected from more than 4,000 participants in Newfoundland and Labrador and Ontario.
The study, Calcium and Vitamin D and Risk of Colorectal Cancer: Results from a Large Population-based Case-control Study in Newfoundland and Labrador and Ontario, was published Sept. 22 in the Canadian Journal of Public Health.
Data for the study were obtained from the Newfoundland Familial Colorectal Cancer Registries and the Ontario Familial Colorectal Cancer Registries. Participants willing to participate in the study filled out a family history questionnaire, personal history questionnaire and food frequency questionnaire.
Results of the study showed that overall, higher calcium and vitamin intake are associated with lower risk of colorectal cancer in both Newfoundland and Labrador, and Ontario. For people with low intake or calcium and vitamin intake from foods, supplements containing the two nutrients are associated with reduced risk of colorectal cancer. And although Newfoundland and Labrador has the highest incidence of colorectal cancer in Canada, people in Newfoundland and Labrador have lower calcium intake and eat less fruits and vegetables than their Ontario counterparts.
The study was part of Zhuoyu Suns M.Sc. thesis under the supervision by Memorial faculty members Drs. Peter Wang, Barbara Roebothan, Sharon Buehler and Yanqing Yi. It was supported by several funding agencies including the Canadian Institutes of Health Research and the Newfoundland and Labrador Centre for Applied Health Research.