Plant-Based Diet Linked to Lower Risk of Prostate Cancer Progression: JAMA

Plant-based diets have been linked to numerous health and environmental benefits, including the prevention of various cancers. However, the impact of a plant-based diet on individuals already diagnosed with prostate cancer is less understood. This study aims to examine the association between postdiagnostic plant-based dietary patterns and the risk of prostate cancer progression and prostate cancer-specific mortality.

The study analyzed data from men with biopsy-proven nonmetastatic prostate cancer enrolled in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) between 1999 and 2018. Participants completed a comprehensive diet and lifestyle questionnaire, including a validated food frequency questionnaire (FFQ), between 2004 and 2016. Overall plant-based diet index (PDI) and healthful plant-based diet index (hPDI) scores were calculated from the FFQ.

The key findings of the study were:

• The study included 2,062 men with a median age of 65.0 years. Most participants identified as White (95%), followed by African American (3%), Asian or Pacific Islander (<1%), Latino (1%), and American Indian or Alaska Native (<1%).

• The median time from prostate cancer diagnosis to the completion of the FFQ was 31.3 months.

• The median follow-up after the FFQ was 6.5 years, during which 190 progression events and 61 prostate cancer-specific mortality events were observed.

• Men in the highest quintile of PDI had a 47% lower risk of cancer progression compared to those in the lowest quintile (HR 0.53; 95% CI 0.37-0.74; P for trend = .003).

• While the overall hPDI was not associated with a significant risk reduction, among 680 individuals with Gleason grade 7 or higher at diagnosis, the highest hPDI quintile was associated with a 55% lower risk of progression compared to the lowest quintile (HR 0.45; 95% CI 0.25-0.81; P for trend = .01).

The study's findings suggest that a plant-based diet may be beneficial for men with prostate cancer, particularly for those with higher Gleason grades. Higher intake of plant-based foods after a prostate cancer diagnosis could help reduce the risk of cancer progression. The results support the potential role of nutritional assessment and counseling for patients with prostate cancer to establish healthy dietary practices.

Higher intake of plant foods following a prostate cancer diagnosis was associated with a lower risk of cancer progression. Nutritional assessment and counseling may be recommended for prostate cancer patients to support overall health and well-being.

Reference:

Liu, V. N., Van Blarigan, E. L., Zhang, L., Graff, R. E., Loeb, S., Langlais, C. S., Cowan, J. E., Carroll, P. R., Chan, J. M., & Kenfield, S. A. (2024). Plant-based diets and disease progression in men with prostate cancer. JAMA Network Open, 7(5), e249053. https://doi.org/10.1001/jamanetworkopen.2024.9053