Calorie Restriction and Colon Cancer

Michael Lam, MD, MPH
www.DrLam.com

Our diet is a key factor in keeping gut and colon cancer at bay, and preliminary studies in mice have suggested that the best diet to counter cancer is to eat in healthier and smaller food portions.

Investigators at the US National Cancer Institute, in Bethesda, Maryland found that cancer-prone mice which were fed either a restricted-calorie diet or a diet rich in olive oil, fruits and vegetables were up to 60% less likely to develop pre-cancerous colon polyps compared with mice fed regular diets. As such, the lead researcher Dr. Volker Mai has advised individuals who want to prevent intestinal and colon cancers to "avoid overeating and consume a healthier diet rich in beneficial fatty acids (and) high in fruits and vegetables".

Dr. Mai's study placed mice on 5 different variables. These mice were specially bred with a gene that left them highly susceptible to intestinal cancers. The mice were then put on one of five diets - a regular diet, a regular diet plus moderate exercise, a high-fat diet, a calorie-restricted (40% less) diet, or a diet high in olive oil, fruits and vegetables.

Each mouse's gut was then examined for the number of polyps -- small pre-cancerous growths -- at the end of the study. The results demonstrated how significantly the diet affects the rate of cancer growth. The mice on the olive oil, fruit and vegetable regimen displayed 40% fewer polyps within the intestines and colon, and there was a full 60% less polyp development among the mice on the calorie-restricted diet. The mice who had exercised had a slight reduction in polyp development, whereas the most cancer-prone mice were those on the high-fat regimens.
Many studies have concluded that simply by reducing daily calorie intake is helpful in keeping cancer away, and it is almost universally accepted that diets heavy in fruits, vegetables and healthy oils work to fight a host of illnesses.

While we cannot say with certainty that the same results apply to men as they do in mice, strong similarities do exist between us. Although the mechanisms by which various foods affect health remain unclear, it is likely low-calorie, plant-based diets may alter levels of hormones in the body that influence cancer development.