Colorectal cancer is the second leading cause of cancer-related deaths in the U.S.
by C.H. Weaver M.D.
Due to the high prevalence of this cancer, prevention and early detection are important areas of research. Two recent studies suggest that making healthy lifestyle choices can reduce the likelihood of developing cancer or postpone the age at which cancer develops.
The first study evaluated the impact of alcohol and tobacco use on age at colorectal cancer diagnosis.1Researchers assessed information from more than 160,000 colorectal cancer patients. Alcohol and tobacco use were classified as current, past, or never.
- Current use of alcohol or tobacco was linked with a younger age at colorectal cancer diagnosis.
- Among those who were current users of both alcohol and tobacco, the average age at colorectal cancer diagnosis was 63 years. This was almost eight years younger than the average age at colorectal cancer diagnosis among individuals who never smoked or drank.
The researchers suggest that in the future, it may be possible to use information about a variety of factors—including alcohol and tobacco use—to individualize colorectal cancer screening guidelines. Optimizing colorectal cancer screening is important because screening can both detect colorectal cancer at an early stage, when it is most curable, and can also prevent colorectal cancer by detecting precancerous colorectal changes.
A second study assessed the impact of fruit and vegetable intake on the risk of developing colorectal polyps.2 Colorectal polyps are small growths within the colon or rectum that are thought to be precursors to cancer. While other dietary factors have been found to influence colorectal cancer risk (high red meat intake, for example, appears to increase risk), the evidence regarding a possible protective role of fruit and vegetable intake has been less consistent.
To evaluate the link between fruit and vegetable intake and colorectal polyps, Researchers affiliated with the Nurses’ Health Study evaluated the link between diet and polyps among more than 34,000 women who had undergone a colonoscopy or sigmoidoscopy between 1980 and 1998. The study suggested that a diet high in fruit may reduce the risk of developing colorectal polyps:
- Compared to women who ate one or fewer servings of fruit per day, women who ate five or more servings of fruit per day were 40% less likely to develop colorectal polyps.
- There was little evidence that high vegetable intake reduced the risk of colorectal polyps.
Coupled with earlier studies that show that physical activity reduces colorectal cancer risk, these studies provide further evidence that healthy lifestyle choices reduce the risk of developing colorectal cancer and improve colorectal cancer outcomes.
1 Zisman AL, Nickolov A, Brand RE et al. Associations Between Age at Diagnosis and Location of Colorectal Cancer and the Use of Alcohol and Tobacco. Archives of Internal Medicine. 2006;166:629-634.2 Michels KB, Giovannucci E, Chan AT, et al. Fruit and vegetable consumption and colorectal adenomas in the Nurses’ Health Study. Cancer Research. 2006;66:3942-3953.