A plant-based diet that includes plenty of fresh fruits and vegetables could reduce both the progression of prostate cancer and the likelihood that it will return, new research shows.
After skin cancer, prostate cancer is the second-most common cancer in men, with an estimated 288,300 new cases and 34,700 deaths projected for this year. Risk factors include age, race, and certain gene mutations.
The study notes that plant-based diets have been linked to multiple health benefits. For prostate cancer, individual plant foods, such as tomatoes with lycopene, appear to reduce prostate cancer incidence and mortality. However, less is known about plant-based dietary patterns and prostate cancer survivorship.
Study lead author Vivian Liu and her team focused on men who already had prostate cancer and were at risk of the cancer growing or returning after treatment. The plant-based sub-study research began in 2004 and involved 2,038 men with early-stage prostate cancer.
The analysis involved scoring for certain foods, and though the participants reported the amounts they ate, it was not possible to state the amounts as individual or recommended servings of fruits and vegetables. Instead, they completed questionnaires about how often they ate about 140 foods and beverages, including such items as broccoli, red meat, and potatoes.
The researchers also took other factors into account, including exercise, smoking, diabetes, family history of prostate cancer, household income, education level, height, body mass index, alcohol use, and multivitamin and supplement use.
At the end of the study, the researchers found that the disease advanced in 204 of the participants during the study period. But notably, men with prostate cancer who reported diets containing the highest amounts of plants had a 52 percent lower risk of disease progression and a 53 percent lower risk of recurrence compared with those whose diets had the lowest amounts of plants.
“This study indicates that plant-based dietary patterns are associated with lower risk of [prostate cancer (PC)] progression and recurrence, particularly among older men and those who reported a higher intensity walking pace,” the study notes.
“PC survivors may be recommended diet and exercise counseling to improve clinical outcomes after PC diagnosis,” the study states.
The results of this yet-to-be published observational study was presented at the 2023 American Society of Clinical Oncology Genitourinary Cancers Symposium. The research was a sub-study of the Cancer of the Prostate Strategic Urologic Research Endeavor, or CaPSURE, which is a large multisite study of 15,000 men started in 1999 and looking at many aspects of prostate cancer.
Next, Liu and her colleagues plan to analyze plant-based diets in relation to prostate cancer-specific mortality, or death, and quality of life at specific intervals (two, five, and 10 years) following diagnosis.
The conclusion is similar to that of previous studies that suggest a beneficial role of specific plant-based foods on prostate cancer, such as tomatoes, and the potentially harmful role of meat, dairy, and other animal products. Last year, a study published in scientific, peer-reviewed publication Journal of Urology found that greater consumption of plant-based foods lowers the risk of prostate cancer for men under 65.
Other benefits of plant-based diet
In addition to helping reduce the risk and return of prostate cancer, eating fruits and vegetables has many other health benefits, such as reducing the risk of type 2 diabetes and cardiovascular disease, and contributes to a longer life span, according to a number of other previous studies.
A study published last year in the scientific journal Diabetologia found that the consumption of plant-based foods such as fruits, vegetables, nuts, coffee, and legumes were associated with a lower risk of developing Type 2 diabetes.
Another study published in the medical journal Dietary Science and Practice found that eating a plant-based diet reduces inflammatory dietary advanced glycation end-products (AGEs)—a biomarker implicated in chronic diseases such as Type 2 diabetes and cardiovascular disease—by nearly 80 percent. Comparatively, a diet that includes meat and dairy products reduced AGEs by 15 percent.
“Simply swapping fatty meat and dairy products for a low-fat plant-based diet led to a significant decrease in advanced glycation end-products—inflammatory compounds found to a greater degree in animal products than plants,” lead study author Hana Kahleova, MD, PhD, director of clinical research at the Physicians Committee for Responsible Medicine (PCRM), said in a statement.