Abstract B135: A Mediterranean dietary intervention for reducing colon cancer risk

Abstract

Abstract B135 Epidemiological and animal studies indicate that the major components of the traditional Cretan-Mediterranean diet have great promise for the prevention of colon cancer while improving overall health. We designed an exchange-list diet that would target 1) an increase in amount and variety of fruits and vegetables, 2) an increase in whole grains and 3) a decrease in n-6 fatty acids with increased n-3 and n-9 fatty acids. The exchange list approach provided flexibility in food choices for meeting nutrient goals. In this ongoing study we are recruiting study participants at increased risk for colon cancer. Subjects are being randomized to a modified Mediterranean diet or a Healthy People 2010 diet for 6 months, each of which involves intensive dietary counseling. Dietary intake data, blood samples and biopsies of normal colonic mucosa from flexible sigmoidoscopy are being collected and analyzed. Thus far 45 subjects have been enrolled with a mean age of 52 years, mean BMI of 28 kg/m2 and 67% were female. Two thirds of the subjects had a family history of colon cancer and the remainder had a personal history of adenomas. Dietary intakes of mono-unsaturated fats increased by about 70% and fruit and vegetables intakes doubled, but caloric intake did not change appreciably in the Mediterranean arm. This indicates that the exchange list diet was an effective tool. HPLC-MS-MS methods were developed to profile prostaglandins and leukotrienes in granulocytes and colonic mucosa using a single chromatographic run. Thus far granulocyte samples from 23 subjects have been analyzed there was a trend for decreases in several eicosanoids in samples from the Mediterranean arm while changes in the Healthy Eating arm were more variable. These preliminary data indicate that subjects can make large dietary changes and that this may impact on inflammation. Effects on biomarkers in the colonic mucosa are ongoing and will be important to evaluate the potential preventive effects of a Mediterranean type of diet. Supported by NIH grant 1RO1CA120381. Citation Information: Cancer Prev Res 2008;1(7 Suppl):B135.