The Power of Vegetables Falls Short for Prostate Cancer Progression
Some studies have found correlations between men who eat a typical high-fat “Western” diet and worse prostate cancer outcomes. Conversely, some studies have found that men who eat a typical “Mediterranean” diet that is high in vegetables, fruits, and unsaturated fats have better prostate cancer outcomes.
Based on these observations, the Men’s Eating and Living (MEAL) study sought to determine if encouraging men to eat more vegetables would decrease rates of prostate cancerprogression. The clinical trial randomly assigned more than 400 men with early-stage prostate cancer into two groups. One group participated in phone counseling to encourage them to eat more vegetables; the other group received only written information about diet and prostate cancer.
The intervention worked at getting men to eat a healthier diet; men who had the nutritional counseling ate more vegetables compared to men in the control group, as evidenced with blood tests. Men who had counseling also ate less red meat and less fat.
However, the trial did not find a significant difference between disease progression rates between the two groups of men. In both groups, about 55% of men saw their prostate cancer progress within two years.
The authors noted that the study may have been underpowered to identify any differences in the results. It is possible that longer-term results could reveal different findings.
There are many benefits of eating vegetables, as they are rich in vitamins and minerals, and low in fat and calories. Getting or staying healthy after a prostate cancer diagnosis has other benefits as well. The study’s lead author, Dr. J. Kellogg Parsons of the University of California, San Diego, told the New York Times, “The study doesn’t give license for folks to not eat a healthy diet. Lots of other research in prostate and other cancers has shown that men who are more robust and healthier in general tolerate their treatment much better.”
Parsons JK, Zahrieh D, Mohler JL, et al. Effect of a Behavioral Intervention to Increase Vegetable Consumption on Cancer Progression Among Men With Early-Stage Prostate Cancer: The MEAL Randomized Clinical Trial. JAMA. 2020;323(2):140–148. doi:10.1001/jama.2019.20207