Short Version edit
A 2005 secondary prevention study on prostate cancer published by Dr. Dean Ornish, showed that a year long "intensive lifestyle change" consisting of a vegan diet, aerobic exercise, stress management and weekly group therapy resulted in a 4% reduction in PSA levels with no patients having to leave the study due to disease progression. In contrast, the control group for this study experienced a 6% increase in PSA levels with 6 patients having to leave the study for conventional treatment due to disease progression.(footnote)