Colon cancer survivors with diets heavy in red meat and fatty foods are more than three times as likely to suffer a recurrence of their disease or die from it than those who avoid such foods, a study found.
Previous studies had shown that a high-fat diet, especially one with lots of red meat, may increase a person's risk of developing colon cancer, a leading cancer killer.
This study, published on Wednesday in the Journal of the American Medical Association, was the first to show how diet affects whether colon cancer returns in people previously treated for it, the researchers said.
The study tracked 1,009 people treated with both surgery and chemotherapy for stage III colon cancer - cancer that had spread from the large bowel area to the lymph nodes but not other organs. They were followed on average for five years.
Combined with rectal cancer, colon cancer accounts for about 50,000 deaths annually in the United States alone.
After questioning them about what they ate, the researchers detected two distinct dietary patterns.
One was a "Western" pattern with lots of red and processed meats, sweets, desserts, French fries and refined grains. The other was a "prudent" pattern avoiding those foods and including lots of fruit and vegetables, poultry and fish.
Those who most closely followed the "Western" pattern experienced a risk about 3.3 times higher for colon cancer recurrence or death than those following the "prudent" one.
"We know that a variety of dietary factors affect people's risk of developing colon cancer, including high red meat intake and certain sugary foods," Jeffrey Meyerhardt of Dana-Farber Cancer Institute in Boston and Harvard Medical School, who led the study, said in a telephone interview.
"But what there really wasn't any data on until now is how these factors may affect people who already have colon cancer. And it's a question a lot of people with colon cancer ask all the time - 'What dietary things should I do, in addition to standard treatment, to help my outcome?'" Meyerhardt added.
Mary Young, a vice president of the National Cattlemen's Beef Association in Colorado, noted that the study did not implicate any one food as raising health risks.
"However, as a dietitian, I would not recommend the (Western) dietary pattern identified in this study because it does not include the variety and moderation important to a healthy diet. Instead, I recommend people choose a diet rich in fruits, vegetables, whole grains, low-fat dairy, and lean meats, such as lean beef," Young said in a statement.
Katherine Tucker, a professor of nutritional epidemiology at Tufts University in Boston who was not part of the study, called the research very well done.
"Colon cancer is one of the problems that's been associated with greater red meat consumption. I think that what some people haven't been able to sort out is whether lean meat in moderation has an effect," Tucker added in an interview arranged by the beef association.