Objectives: To evaluate, in a feasibility study, the adherence to a low-fat diet by men with prostate cancer. Evidence is growing that a low-fat diet affects the development and course of prostate cancer. To design preventive and therapeutic interventions, it is important to know whether men will adhere to these nutritional recommendations, particularly when motivated by the diagnosis of prostate cancer.
Methods: Men with elevated prostate-specific antigen levels, most of whom were recently treated for prostate cancer, were randomized to one of four dietary regimens for which they received nutritional counseling: a low-fat diet (15% fat or less) with supplements (vitamin E and selenium), a low-fat diet (15% fat or less) without the supplements, the supplements alone, and a control group. Adherence was evaluated by the change in weight, fat intake, free fatty acids, cholesterol, high-density and low-density lipoproteins, and triglycerides during a 12-month period.
Results: The mean age of the 48 participants was 66 years. For those counseled about a low-fat diet, the mean change in the percentage of energy (kilocalories) in the diet from fat was greater after 3 months (-8.6% versus +2.1%, P <0.001) and 12 months (-9.8% versus -1.6%, P = 0.001). Three months after starting the intervention, those randomized to low-fat dietary counseling had lost 2 kg, on average, compared with 0.8 kg lost by those who did not receive this counseling (P = 0.09). At 12 months, those receiving low-fat counseling had lost 2.8 kg, on average, compared with 0.5 kg gained among the other groups (P = 0.02).
Conclusions: With appropriate counseling, men with prostate cancer can adhere to a low-fat dietary intervention for a 12-month period.