High-carb diet may increase risk of colorectal-cancer recurrence
November 20, 2012 | by Hiu Chung So
Colorectal cancer is one of the deadliest and most prevalent cancers in the United States, accounting for more than 140,000 new cancer cases and 50,000 deaths this year. It is also a cancer for which the risk can be managed, in part, with lifestyle choices.
Researchers have known that a diet high in red and processed meats is linked to a higher chance of developing colorectal cancer. Now new research suggests that high-carbohydrate foods might be linked to a higher risk as well.
In a study published online on Nov. 7 in the Journal of the National Cancer Institute, researchers from Dana-Farber Cancer Institute examined more than 1,000 stage III colon cancer patients who had undergone surgery and who participated in a follow-up chemotherapy clinical trial. During the chemotherapy trial and six months afterward, participants recorded the foods and beverages they consumed.
After evaluating participants’ diets and analyzing how quickly their blood sugar likely rose based on those diets (a measure known as glycemic load), the researchers found that the participants with the highest glycemic load had an 80 percent higher risk of cancer recurrence or death compared to those with the lowest glycemic load levels.
Marwan Fakih, M.D., professor in City of Hope’s Department of Medical Oncology & Therapeutics Research, was not involved with this study but said the results suggest colorectal cancer patients should pay close attention to their diet and exercise habits.
“The findings bolster existing evidence that linked insulin resistance and a Western diet, which is high in carbohydrates, to an increased risk of colorectal cancer recurrence,” Dr. Fakih said. “Obesity played a factor as well, since the connection between a high glycemic load diet and a greater risk of colorectal cancer recurrence or death was only seen in patients with a body mass index of 25 or higher.”
Dr. Fakih said, given this and other studies on the subject, overweight and obese colorectal cancer patients should likely limit their carbohydrate intake, avoid a Western diet (one high not just in refined carbohydrates but also red meats and other processed foods) and enroll in an exercise and weight control program if they need help losing weight.
Such advice isn’t bad for the rest of us either.
For more information about colorectal cancer treatment, screening and research at City of Hope, visit our colorectal cancer program page.