After surgery or radiation, many prostate cancer patients take hormonal therapy to hopefully stave off cancer recurrence, but for many men hormone therapy is no easy ride. It often produces side effects like hot flashes, a decrease in sex drive, and weakened bones.
Searching for alternatives, scientists at the University of California, San Diego instructed 14 men with recurrent prostate cancer to adopt a diet full of whole grains, vegetables, fruits, and legumes, and beans.*
Dangers of Western diet
“Epidemiological studies have associated the Western diet [high in animal foods and low in fiber-rich plant foods] with not only prostate cancer incidence but also with a greater risk of disease progression after treatment,” wrote lead author Gordon Saxe, MD, PhD, of Moores UCSD Cancer Center and colleagues.
“Conversely, many elements of plant-based diets have been associated with reduced risk of progression.”
Because starting new dietary habits can be stressful, the men were also instructed in stress relaxation techniques – meditation, yoga, and tai chi.
The best predictor of survival and cancer spread is the rate at which PSA (prostate specific antigen) levels rise. Generally, the faster PSA rises, the greater the risk of cancer progression. Decreasing levels indicate that the cancer has stopped growing, and may even be shrinking.
So for two periods of time, the pre-study period (the six months before the men adopted their new diet) and the study period (the men’s six-month dietary intervention period), the scientists monitored PSA levels.
Compared to the pre-study period, the dietary-change period showed a significant decrease in the rate of PSA rise. In fact, nearly half the men showed a drop in PSA levels while following their new plant-based diet.
Prostate cancer diet
“Our findings suggest that the intervention we employed may have resulted in a slowing of disease progression and, in a few patients, possibly disease reversal,” concluded the authors.
“These results provide preliminary evidence that adoption of a plant-based diet, in combination with stress reduction, may attenuate disease progression and have therapeutic potential for clinical management of prostate cancer.”
Integrative Cancer Therapies, 2006; 5: 206