Researchers at the University of Michigan, Ann Arbor, USA, are comparing the effect of a Mediterranean diet – high in olive oil, nuts and fish – with standard healthy eating on colon cancer, reports the news agency United Press International.

Zora Djuric and researchers at the University of Michigan Comprehensive Cancer Center are looking at adults aged 21 or older who have had colon polyps, colon cancer or a family history of colon cancer.

Participants will be randomly assigned to follow either the Mediterranean diet or the Healthy People 2010 diet, promoted by the US Department of Health and Human Services, for six months.

A dietitian will work closely with each participant by telephone. Participants can choose foods they prefer from recommended food group lists.

The Mediterranean diet focuses on vegetables, whole grains, fruits, fish and olive oil, and limits high-fat meats and processed foods. The Healthy People 2010 diet involves eating plenty of fruits and vegetables, whole grains and a moderate fat intake with limits on saturated fat.