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Men interested in preserving their urological health may benefit from eating more vegetables and fruits, researchers reported.

A trio of studies presented at the American Urological Association (AUA) virtual meeting suggested that plant-based diets were associated with a decreased risk of erectile dysfunction (ED), lower PSA rates, and possibly a lower rate of total and fatal prostate cancer among younger men.

"We can summarize this session succinctly," said AUA press conference moderator Stacy Loeb, MD, of NYU Langone Health in New York City, who also presented one of the studies.

"Eat more plants for your prostate and your erections," she advised.

Plant-Based Protection

Investigators at the University of Miami (UMiami) Miller School of Medicine used the National Health and Nutrition Examination Survey (NHANES) to evaluate the association between a plant-based diet and PSA levels. Using Food Frequency Questionnaire dietary data they calculated a plant-based diet index (PDI) and healthful plant-based diet index (hPDI).

Ali Mouzannar, MD, reported that in a cohort of 1,399 men, those with a higher consumption of healthy plant-based diet (high hPDI scores) had a decreased probability of having an elevated PSA (OR 0.47, 95% CI 0.24-0.95).

"It seems plant-based diets have protective effects against prostate cancer," Mouzannar said during the press session. "We still need more insight and more clinical trials to establish the causative effect, but there have been multiple associations between lower risk of prostate cancer, lower risk of elevated PSA with a plant-based diet."

He added that "it also works the other way around -- meat has been shown to be associated with a high rate of aggressive prostate cancer, and high risk of recurrence."

In a second UMiami-based study, Ruben Blachman-Braun, MD, Ranjith Ramasany, MD, and colleagues used NHANES data base to evaluate 2,549 men, 57.4% of whom had some degree of ED. He reported that risk factors, such as increased age, BMI, hypertension, diabetes, and history of stroke, were all strongly associated with the risk of ED.

"However, increasing plant-based consumption was associated with a decreased risk of erectile dysfunction," Blachman-Braun pointed out (OR 0.98, 95% CI 0.96 0.99).

Loeb and colleagues conducted a prospective study involving 27,243 men, who were followed up to 28 years, in the Health Follow-up study.

They found that in men ages ≤65 at diagnosis, greater overall consumption of plant-based diet was associated with a lower risk of advanced prostate cancer (HR 0.68, 95% CI 0.42-1.10). Among younger men, greater consumption of a healthful plant-based diet was associated with lower risks of total prostate cancer (HR 0.81 95% CI 0.70-0.95), and fatal disease (HR 0.53, 95% CI 0.32-0.90).

"This is really encouraging given the many health and environmental benefits of plant-based diets," Loeb said. "And we believe they should be recommended for men who are concerned about the risks of prostate cancer."

'A Win-Win'

On the issue of the environmental impact of following plant-based diets, Mouzannar noted that higher meat consumption is associated with greenhouse gas emissions, water issues, decreased biodiversity. "There is a significant effect in following plant-based diets," he said. "Whether that's in individuals by promoting a healthy lifestyle and decreasing the risk of multiple cancers -- in addition to prostate cancer, specifically -- or the environmental effects."

"I see it as a win-win," Loeb said. "There's not really a downside here. You're going to decrease your risk of aggressive prostate cancer and elevated PSA, and increase your chances of preserving erectile function, and it's just better for the planet as a whole."

Ramasany suggested that future observational studies "should at least focus on men switching to a plant-based diet, and see what happens to PSA, to prostate cancer recurrence and testosterone levels."

He acknowledged that "Diet studies are always tough to do," but "this would be an easy enough intervention to try."