Experts have uncovered evidence that a plant based diet may reverse prostate cancer. The research comes from several sources, including Dean Ornish, MD, who also has shown that it’s possible to treat and even reverse heart disease by eating a diet based on plant foods, and without using drugs.
One of Ornish’s studies involved 93 men with prostate cancer who had chosen to forego any form of conventional treatment. The men had a starting PSA of 4 to 10 ng/mL and Gleason scores less than 7. They were randomly assigned to either undergo usual care (active surveillance: 49 men; lifestyle modifications recommended by doctor but not the Ornish diet) or to switch to a plant-based diet, exercise, and stress management (44 men).
After one year, the men in the plant-based diet group showed a 4 percent decline in prostate-specific antigen (PSA) values, while those in the control group had a 9 percent increase. Another significant difference between the two groups was in the growth of prostate cancer cells: a 70 percent inhibition of serum-stimulated growth in the plant-based diet group compared with a 9 percent inhibition in the control group.
At the two-year follow-up of this study, 27 percent (13 of 49) of the men following active surveillance had undergone conventional prostate cancer treatment (e.g., radiotherapy, hormone therapy, radical prostatectomy) compared with 5 percent (2 of 43) in the plant-based diet group. No deaths occurred during the two-year period, and no other significant differences were seen between the two groups.
Based on these findings, Ornish and his team concluded that “Patients with early-stage prostate cancer choosing active surveillance might be able to avoid or delay conventional treatment for at least 2 years by making changes in their diet and lifestyle.”
The reasons why a plant-based diet seems to reverse prostate cancer is unclear, but based on a comparison of prostate biopsies obtained before and after the dietary changes, Ornish noted a shift in gene regulation. That is, the vegan diet seemed to reprogram, or downregulate, the genes in the prostate gland.
Frattaroli J et al. Clinical events in prostate cancer lifestyle trial: results from two years of follow-up. Urology 2008; 72(6): 1319-23
Ornish D et al. Intensive lifestyle changes for reversal of coronary heart disease. JAMA 1998 Dec 16; 280(23): 2001-7
Ornish D et al. Intensive lifestyle changes may affect the progression of prostate cancer. Journal of Urology 2005; 174(3): 1065-69
Ornish D et al. Changes in prostate gene expression in men undergoing an intensive nutrition and lifestyle intervention. Proceedings of the National Academy of Sciences USA 2008 Jun 17; 105(24): 8369-74