Building on basics

Lipid profiler
(continued)

Most cancer deaths are caused by metastasis. Cut off the tumor's food source, keep it from metastasizing, and you have a disease that is local and manageable instead of the nation's second-leading killer.

"If we could reduce the incidence of breast cancer metastasis, it would be a much more treatable disease," says Erickson, "especially since fewer than 10 percent of all cases of breast cancer have metastasized at the time of early diagnosis."

Erickson further believes that the metabolites of conjugated linoleic acid reduce the body's production of prostaglandins, a tumor-promoting, hormone-like substance which can also suppress the immune system and hence, alter the transmission of cellular events that cause cancer.

That's not to say you should make triple cheeseburgers a regular part of your diet. In the foods that have it, conjugated linoleic acid is found only in small amounts. Supplementation seems a better way to go, and no one is sure how much to take, how it works in people, or whether conjugated linoleic acid in food will do the trick. It may, Erickson hypothesizes, some day be considered a supplemental therapy for breast cancer or other-fat sensitive cancers such as colon and prostate cancer.

Human cancer trials of this intriguing lipid could start in a few years, once Erickson's current project is finished and a human study done in collaboration with the U.S. Department of Agriculture Metabolic Research Unit in San Francisco is completed.

In that study, Agriculture Department scientists analyzed the diet of volunteers who lived for 120 days in a special metabolic research facility. They stayed there 24 hours a day, seven days a week, for the duration of the experiment. The volunteers were analyzed under strict laboratory conditions. "It's not like a free-living study, where you give people supplements to take but you have no way of knowing if they did what they were supposed to," says Erickson.

Not surprisingly, healthy volunteers for this kind of 24-hour-a-day study are difficult to come by, and drop-out rates are high. Still, information from a dozen women volunteers who received conjugated linoleic acid in their food as part of the experiment in 1998 is waiting to be analyzed.

Meanwhile, in Erickson's biology laboratory, mice injected with breast tumor cells nibble their special diets of grains and conjugated linoleic acid, a whitish substance that in mice-meal looks like parmesan cheese. What will be the results? Fat-lovers of the world await.

Hubbard and staff research associate Debora Lim whip up mice meal inside the Department of Nutrition at UC Davis.