Dietary Modification - Low Fat Diet

PURPOSE: A high fat diet and sedentary lifestyle may predispose men to prostate cancer through effects on serum factors such as hormones. We evaluated the effects of a low fat, high fiber diet and exercise intervention on serum stimulated growth of established prostate cancer cell lines.

MATERIALS AND METHODS: Fasting serum was obtained from 13 overweight men before and after undergoing an 11-day low fat, high fiber diet and exercise intervention. Serum was also obtained from 8 men who had complied with the regimen for a mean of 14.2 years. Hormone dependent LNCaP and independent PC-3 prostate cancer cell lines were grown in culture medium containing 10% of subject pre-intervention or post-intervention serum and viable cells were counted after 48 hours. Anthropometry, serum free testosterone, lipids and glucose were measured in all subjects.

RESULTS: Post-intervention serum from each of the 11-day intervention subjects reduced LNCaP cell growth by a mean of 30% compared with pre-intervention serum from each (p<0.01). LNCaP cell growth in serum from long-term subjects was 15% below that of post-intervention serum (p<0.01). There was no difference in the growth of PC-3 cells when cultured with serum from either intervention group. Serum free testosterone, body weight, glucose and lipids were significantly reduced in 11-day subjects.

CONCLUSIONS: A low fat, high fiber diet and exercise intervention resulted in serum changes that significantly reduced the growth of androgen responsive LNCaP prostate cancer cells in vitro.