Growth inhibitory effect of low fat diet on prostate cancer cells: results of a prospective, randomized dietary intervention trial in men with prostate cancer.
Study Goal
The researchers aimed to evaluate the effect of a low-fat diet on serum factors affecting prostate cancer cell growth in men with prostate cancer.
Results Summary
The low-fat diet significantly decreased the growth of LNCaP prostate cancer cells compared to a Western diet, with changes in serum fatty acid levels (reduced omega-6 and increased omega-3) correlating with reduced cancer cell growth. No significant changes were observed in other serum markers like prostate-specific antigen or sex hormones.
Population
18 men with prostate cancer who had not received prior therapy.
Effective Dosage
15% kcal from fat, high fiber, soy protein supplemented diet.
Duration
4 weeks
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
low fat (15% kcal), high fiber, soy protein supplemented diet | decrease | growth of LNCaP cells | men with prostate cancer | - | significantly decreased | #1 |
low fat (15% kcal), high fiber, soy protein supplemented diet | no change | serum prostate specific antigen | men with prostate cancer | no significant change | no significant between group changes | #2 |
low fat (15% kcal), high fiber, soy protein supplemented diet | no change | sex hormones | men with prostate cancer | no significant change | no significant between group changes | #3 |
low fat (15% kcal), high fiber, soy protein supplemented diet | no change | insulin | men with prostate cancer | no significant change | no significant between group changes | #4 |
low fat (15% kcal), high fiber, soy protein supplemented diet | no change | insulin-like growth factor I and II | men with prostate cancer | no significant change | no significant between group changes | #5 |
low fat (15% kcal), high fiber, soy protein supplemented diet | no change | insulin-like growth factor binding proteins | men with prostate cancer | no significant change | no significant between group changes | #6 |
low fat (15% kcal), high fiber, soy protein supplemented diet | decrease | serum triglyceride levels | men with prostate cancer | - | decreased | #7 |
low fat (15% kcal), high fiber, soy protein supplemented diet | decrease | linoleic acid (omega-6) levels | men with prostate cancer | - | decreased | #8 |
- | decrease | omega-6 fatty acid | - | - | decreased | #9 |
- | increase | omega-3 fatty acid | - | - | increased | #10 |
low fat diet | decrease | human LNCaP cancer cell growth | men with prostate cancer | - | resulted in changes in serum fatty acid levels that were associated with decreased | #11 |
PURPOSE: A high fat Western diet and sedentary lifestyle may predispose men to prostate cancer through changes in serum hormones and growth factors. We evaluated the effect of a low fat diet on serum factors affecting prostate cancer cell growth by performing a prospective, randomized dietary intervention trial in men with prostate cancer. MATERIALS AND METHODS: We randomized 18 men with prostate cancer who did not receive prior therapy to a low fat (15% kcal), high fiber, soy protein supplemented diet or a Western (40% kcal fat) diet for 4 weeks. Fasting serum was collected at baseline and after the intervention to measure prostate specific antigen, sex hormones, insulin, insulin-like growth factor I and II, insulin-like growth factor binding proteins, lipids and fatty acids. LNCaP cells (ATCC(R)) were cultured in medium containing pre-intervention and post-intervention human serum to assess the in vitro effect of the diet on prostate cancer cell proliferation. RESULTS: Subjects in each group were highly compliant with the dietary intervention. Serum from men in the low fat group significantly decreased the growth of LNCaP cells relative to Western diet serum (p = 0.03). There were no significant between group changes in serum prostate specific antigen, sex hormones, insulin, insulin-like growth factor I and II, and insulin-like growth factor binding proteins. Serum triglyceride and linoleic acid (omega-6) levels were decreased in the low fat group (p = 0.034 and 0.005, respectively). Correlation analysis revealed that decreased omega-6 and increased omega-3 fatty acid correlated with decreased serum stimulated LNCaP cell growth (r = 0.64, p = 0.004 and r = -0.49, p = 0.04, respectively). CONCLUSIONS: In this prospective, randomized dietary intervention trial a low fat diet resulted in changes in serum fatty acid levels that were associated with decreased human LNCaP cancer cell growth. Further prospective trials are indicated to evaluate the potential of low fat diets for prostate cancer prevention and treatment.