A major prospective study of more than half a million UK women conducted over almost 17 years has confirmed that dietary calcium lowers the risk of colorectal cancer.
Cancer Research UK (CRUK), which funded the study, said that it demonstrated the benefits of a healthy, balanced diet for lowering cancer risk.
Colorectal cancer is the third most common cancer worldwide. Incidence rates vary markedly, with higher rates observed in high-income countries. The risk increases for individuals who migrate from low- to high-incidence areas, suggesting that lifestyle and environmental factors contribute to its development.
While alcohol and processed meats are established carcinogens, and red meat is classified as probably carcinogenic, there is a lack of consensus regarding the relationships between other dietary factors and colorectal cancer risk. This uncertainty may be due, at least in part, to relatively few studies giving comprehensive results on all food types, as well as dietary measurement errors, and/or small sample sizes.
Study Tracked 97 Dietary Factors
To address these gaps, the research team, led by the University of Oxford, tracked the intake of 97 dietary factors in 542,778 women from 2001 for an average of 16.6 years. During this period 12,251 participants developed colorectal cancer. The women completed detailed dietary questionnaires at baseline, with 7% participating in at least one subsequent 2