MEN WHO ATE A LOW-FAT DIET WITH FISH-OIL SUPPLEMENTS for four to six weeks before having their prostate removed had slower cancer-cell growth in their prostate tissue than men who ate a traditional, high-fat Western diet, according to a study by researchers at UCLA's Jonsson Comprehensive Cancer Center.
The researchers also found a change in the composition of cell membranes in both healthy cells and cancer cells in the prostates of men on the low-fat, fish-oil-supplement diet. The membranes had heightened levels of omega-3 fatty acids from fish oil and decreased levels of omega-6 fatty acids from corn oil, which may directly affect the biology of the cells, though further studies are needed, says urologic oncologist William Aronson, M.D.
The short-term study, published in Cancer Prevention Research, also found that blood obtained from patients after the low-fat, fish-oil diet slowed the growth of prostate-cancer cells in a test tube, while blood from men on the Western diet did not slow cancer growth.
"The finding that the low-fat, fish-oil diet reduced the number of rapidly dividing cells in the prostate-cancer tissue is important, because the rate at which the cells are dividing can be predictive of future cancer progression," Dr. Aronson says.
With the study's Western diet, 40 percent of the calories came from fat. The fat sources also were typical of the American diet and included high levels of omega-6 fatty acids from corn oil and low levels of fish oil that provides omega-3 fatty acids. With the low-fat diet, 15 percent of the calories came from fat. Additionally, the men on this diet took five grams of fish oil per day to provide omega-3 fatty acids.