In this cohort study of 2062 men higher intake of plant foods after PCa diagnosis was associated with lower risk of cancer progression

[Graham49]

Plant-Based Diets and Disease Progression in Men With Prostate Cancer

Vivian N. Liu, MAS1,2; Erin L. Van Blarigan, ScD1,3; Li Zhang, PhD1,4; et al Rebecca E. Graff, ScD1; Stacy Loeb, MD5; Crystal S. Langlais, PhD1,6; Janet E. Cowan, MA3; Peter R. Carroll, MD, MPH3; June M. Chan, ScD1,3; Stacey A. Kenfield, ScD1,3

Author Affiliations Article Information

JAMA Netw Open. 2024;7(5):e249053. doi:10.1001/jamanetworkopen.2024.9053

Abstract

Importance Plant-based diets are associated with many health and environmental benefits, including primary prevention of fatal prostate cancer, but less is known about postdiagnostic plant-based diet patterns in individuals with prostate cancer.

Objective To examine whether postdiagnostic plant-based dietary patterns are associated with risk of prostate cancer progression and prostate cancer–specific mortality.

Design, Setting, and Participants This longitudinal observational cohort study included men with biopsy-proven nonmetastatic prostate cancer (stage ≤T3a) from the diet and lifestyle substudy within the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) enrolled at 43 urology practices across the US from 1999 to 2018. Participants completed a comprehensive diet and lifestyle questionnaire (including a validated food frequency questionnaire [FFQ]) between 2004 and 2016. Data were analyzed from August 2022 to April 2023.

Exposures Overall plant-based diet index (PDI) and healthful plant-based diet index (hPDI) scores were calculated from the FFQ.

Main Outcomes and Measures The primary outcome was prostate cancer progression (recurrence, secondary treatment, bone metastases, or prostate cancer–specific mortality). The secondary outcome was prostate cancer–specific mortality.

Results Among 2062 participants (median [IQR] age, 65.0 [59.0-70.0] years), 61 (3%) identified as African American, 3 (<1%) identified as American Indian or Alaska Native, 9 (<1%) identified as Asian or Pacific Islander, 15 (1%) identified as Latino, and 1959 (95%) identified as White. Median (IQR) time from prostate cancer diagnosis to FFQ was 31.3 (15.9-62.0) months after diagnosis. During a median (IQR) follow-up of 6.5 (1.3-12.8) years after the FFQ, 190 progression events and 61 prostate cancer–specific mortality events were observed. Men scoring in the highest vs lowest quintile of PDI had a 47% lower risk of progression (HR, 0.53; 95% CI, 0.37-0.74; P for trend = .003). The hPDI was not associated with risk of progression overall. However, 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 with the lowest hPDI quintile (HR 0.45; 95% CI, 0.25-0.81; P for trend = .01); no association was observed in individuals with Gleason grade less than 7.

Conclusions and Relevance In this cohort study of 2062 men with prostate cancer, higher intake of plant foods after prostate cancer diagnosis was associated with lower risk of cancer progression. These findings suggest nutritional assessment and counseling may be recommended to patients with prostate cancer to help establish healthy dietary practices and support well-being and overall health.

[MrG68]

Just so people are aware, this is an observational and questionnaire type study.

[Jpburns]

My previous oncologist was big on a plant-based diet, especially “soy!”

Soy!

[MrG68 in reply to Jpburns]

Maybe you could ask him for the best evidense literature he's got to show that. Then post it on here so others can benefit.

[Mjex in reply to Jpburns]

Doesn't soy mimic testosterone for those still hormone sensitive, which would be a reason not to eat it while on ADT.

[Graham49 in reply to Mjex]

Soya weakly mimics estrogen. Fermented soya is generally considered better. It has vitamin K2, essential amino acids and isoflavones. No clinicals unfortunately.

[j-o-h-n]

Plant based food taste good with graham crackers...

Good Luck, Good Health and Good Humor.

j-o-h-n

[JohnInTheMiddle]

The world is strange. Here we are sort of on a keto-ish diet. I have actually sometimes achieved ketogenesis. But this is obviously not a plant-based diet. My sense is given the amount of pro plan diet based research and the volume of messaging around how plant-based diets are better for people with prostate cancer, that there's a strong motivation to prove that this proposition is true. It's part of the zeitgeist today and the prejudice against meat. I really hope that my approach which is high fat moderate protein and very low carb is a good idea. There's an anecdote. A data point of one. Two years since diagnosis of de novo high-volume metastatic PCa. So far so good.

[Graham49 in reply to JohnInTheMiddle]

If a lot of the fat you eat is olive oil, avocado oil or nuts you might be in the healthy quintile anyway.