Can cheeseburgers fight cancer?

There's a flip side to the cheeseburger's reputation as a greasy, artery-clogging, cancer-causing meal. It is a prime source of a cancer-fighting compound.

Research by Martha Belury, assistant professor of foods and nutrition, Purdue University, found that a polyunsaturated fatty acid called conjugated dienoic linoleic acid (CLA) can inhibit skin cancer in mice. She also discovered that it can inhibit skin cancer during more than one of the three stages of disease development.

CLA is present in ruminant meat, cheese, and processed cheese. Some exists in milk and yogurt, less in poultry, eggs, and corn oil. Heating food - like pan - frying meat or pasteurizing milk - increases the CLA content.

Most cancer-fighting compounds that have been found in food affect only one organ, such as the stomach, skin, or colon, Belury says. "The fact that CLA protects against stomach, mammary, and skin cancers makes it unique. It's an indicator that something is going on here." That "something" is a puzzle with several pieces still missing. Belury added yet another puzzle piece when she found that CLA inhibits cancer during more than one of its three stages of development - initiation, when a cell or cells are...