Adherence to prevention guidelines may lower cancer risk

Abstract

Consistently following diet and physical activity guidelines for cancer prevention reduced overall cancer incidence and mortality as well as the incidence of breast, endometrial, and colorectal cancers, according to the results of a study recently published in Cancer Epidemiology, Biomarkers & Prevention.1 The study demonstrated that adherence to guidelines was associated with reductions of 10% to 45% in all cancer incidences and reductions of 14% to 61% in all cancer mortality rates. The results also demonstrated consistent reductions in the incidence of breast cancer (19% to 60%), endometrial cancer (23% to 60%), and colorectal cancer (27% to 52%) in both men and women. Researchers found no significant associations between adherence to guidelines and the incidence of ovarian or prostate cancer, whereas associations with lung cancer varied according to the specific study analyzed. Poor diet choices, physical inactivity, excess alcohol consumption, and excessive body weight could account for greater than 20% of cancer cases, meaning many cases could be prevented with lifestyle changes, says Lindsay Kohler, MPH, a doctoral candidate at the University of Arizona Mel and Enid Zuckerman College of Public Health in Tucson and the lead author of the study. She and her colleagues reviewed 12 prospective studies published within the past 10 years that analyzed adherence to cancer prevention guidelines recommended by the American Cancer Society and the World Cancer Research Fund International/American Institute for Cancer Research. Study participants varied in age from 25 to 79 years at baseline and primarily were white. Standards for adherence varied in the 12 studies, which led to the wide range of results. Nevertheless, consistent patterns emerged from the review, Kohler says. For example, the researchers found that in one study, women who followed at least 5 of the recommendations were 60% less likely to develop breast cancer than those who adhered to no recommendations. For each additional recommendation that was followed, the risk of breast cancer was reduced by 11%. Kohler points out that the primary limitation of the research was the variation in studies. As a result, she and her team were only able to summarize information, and could not determine causality or more specific figures for reductions in cancer risk. She adds that although adhering to the guidelines will reduce the risk of dying of cancer, it will not eliminate it. Nevertheless, following the recommendations also will reduce the risk of other major diseases.