Low-Fat Diet Doesn't Help Prostate

Sept. 3, 2002 - September is prostate cancer awareness month and results of a new study shed light on what makes up a prostate-healthy diet. Preliminary studies suggested that a low-fat diet can help ward off prostate cancer. But results of a new, stronger study show no evidence of this -- at least not in the short term.

Although no protective effect was seen in the four years of this study, it is possible that a healthy diet sustained over many more years will help prevent prostate cancer, says lead researcher Moshe Shike, MD, in a news release.

The study, conducted at the Memorial Sloan-Kettering Cancer Center, involved 1,350 men without prostate cancer. About half of the men received intensive nutrition counseling to maintain a diet low in fat (no more than 20% of total calories), high in fiber (at least 36 grams per day for a 2000 calorie diet), and including five to eight daily servings of fruits and vegetables. A comparison group received only a brochure with recommendations on healthy eating habits.

The researchers took special care to make sure that the two groups of men had similar risks of developing prostate cancer prior before the study began. They were of similar age, race, and weight, ate similar diets, and had a family history of prostate cancer.

After four years, there was no difference in PSA blood levels. The PSA test can help indicate when a man has prostate cancer. In addition, both the number of men with high PSA levels and the frequency of prostate cancer was the same in both groups.

The "failure to affect PSA levels should not be viewed as definitive evidence that diet has no preventive impact on prostate cancer," says Shike. "The PSA is only an indicator of prostate cancer, and it is possible that diet could impact the growth of prostate cancer without drastically affecting PSA levels, he adds."