A recently published BMC Cancer journal has revealed new findings on the possible preventive effects of physical activity on the risk of colorectal cancer.
Colorectal cancer is one of the most common types of cancer. The frequency is to the extent that certain screening tests have been developed and it has been shown that these screening tests are effective in early detection and treatment of colorectal cancers.
While screening and early detection of colorectal cancer have played a significant role in decreasing the mortality of patients with this condition, about half of patients affected with colorectal cancers do not survive; as they are diagnosed at a later stage.
The dramatic burden of this disease emphasizes the importance of prevention. Colorectal cancer risk factors include a combination of both inherited and environmental factors. A family history of colorectal cancer, certain dietary regimens, a personal history of inflammatory bowel diseases, and adenomatous polyposis are some of these conditions that can increase susceptibility.
Some studies have shown that diet and lifestyle choices, such as a high fiber diet, may help to prevent the development of colorectal cancer. There are some publications studying the preventive effect of physical activity on colorectal cancers, however, the association between physical activity and colorectal cancer among a high-risk population is still unclear.
This systematic review and meta-analysis which has been recently published in the BMC Cancer journal, has focused on the effect of physical activity on colorectal cancers. This study analysed whether the effect of physical activity on the risk of colorectal cancer would be different between different subgroups. They hypothesized that physical activity would have a greater protective effect against cancer risk in those with a family history of colorectal cancer or those with a high body mass index(BMI).
For conducting this study, researchers have searched Medline (which is a database of medical articles) through June 2017 for relevant articles. A total number of 18 studies were included in the final meta-analysis (a statistical method for analysis and summering the data from the extracted articles). There were nine case-control studies and nine prospective cohort studies.
According to the findings of this study, there was a statistically significant overall protective association between physical activity and the risk of colorectal cancers among those who were at high risk. Contrary to the author’s expectations, the study showed no additional protective effect of physical activity in those with a high BMI, or those with a family history of colorectal cancer.
The study found a protective effect of physical activity in reducing colorectal cancer risk regardless of body mass index or family history of cancer. The authors have concluded that physical activity can potentially contribute to the prevention of colorectal cancers especially among those who are at a higher risk.
Written by Nima Makhdami, M.D.
Reference: Shaw, Eileen, et al. “Effects of physical activity on colorectal cancer risk among family history and body mass index subgroups: a systematic review and meta-analysis.” BMC cancer 18.1 (2018): 71.
