Carrying a few extra pounds isn’t just bad for men's figures – it’s unhealthy. Being overweight or obese increases their odds of heart disease and certain types of cancer, including colorectal cancer.
Being overweight not only increases a man’s risk of developing full-blown colorectal cancer, but also influences the progression of the disease.
A new study looked at what role BMI (body mass index) plays in the development of pre-cancerous tumors.
Colorectal adenomas, often called polyps, are tumors that are not cancerous but could develop into cancer. These spots are commonly seen before colorectal cancer is diagnosed, and they tend to return.
Cari M. Kitahara, PhD, MHS, of the Division of Cancer Epidemiology and Genetics at the National Cancer Institute, led the study and collaborated with researchers from the University of Pittsburg, the New York University Medical Center and Queen’s University Belfast in Ireland.
The goal of the study was to learn if being overweight or obese influenced the development of colorectal adenoma incidence and recurrence, along with colorectal cancer.
The researchers worked with data relating to nearly 3,000 men and women between the ages of 55 to 74 who were participating in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.
Study members were randomly assigned to have a colorectal cancer screening with a flexible sigmoidoscopy (an internal examination of the last part of the colon).
Among the participants, 1,213 cases of distal (end of colon near rectum) were identified, along with 752 cases of recurrent (returned) adenoma and 966 cases of colorectal cancer.
When body mass index (BMI) entered the equation, the researchers learned that, compared to men of normal weight, obese men (BMI of 30 kg/m2 or more) were 32 percent more likely to have polyps and 50 percent more likely to have recurring polyps.
Men who were carrying too much weight were also 48 percent more likely to develop colorectal cancer.
“Data from this large prospective study suggest that obesity is important throughout the natural history of colorectal cancer, at least in men, and colorectal cancer prevention efforts should encourage the achievement and maintenance of a healthy body weight in addition to regular screenings,” the authors wrote.
“These observations suggest that obesity contributes to not only colorectal tumor initiation but also progression, and that regular screenings, detection, and removal of colorectal adenomas do not eliminate the risk of colorectal cancer associated with obesity,” the researchers concluded.
This study was published May 28 in the Journal of Clinical Oncology.
The research was funded by the National Cancer Institute of the National Institutes of Health.