Letter to Editor

An Update on “A Plant-Based Diet Prevents and Treats Prostate Cancer”

Stewart Rose and Amanda Strombom*

Plant-Based Diets in Medicine, USA

Submission: June 27, 2024; Published: July 12, 2024

*Corresponding Address: Amanda Strombom, Plant-Based Diets in Medicine, Issaquah, WA, USA, Email: Contact@pbdmedicine.org

How to cite this article: Stewart Rose and Amanda Strombom*. An Update on “A Plant-Based Diet Prevents and Treats Prostate Cancer”. Canc Therapy & Oncol Int J. 2024; 27(2): 556208. DOI:10.19080/CTOIJ.2024.27.556208

Abstract

Since we wrote our article “A Plant-Based Diet Prevents and Treats Prostate Cancer” in your Cancer Therapy & Oncology International Journal, research has continued to show that a plant-based diet can help prevent prostate cancer, and treat it when it has a Gleason score less than 7.

A longitudinal observational cohort study showed a 47% lower risk of progression for those men scoring in the highest quintile of a plant-based diet index. In a prospective cohort study, greater overall plant food consumption was associated with a significantly lower risk of fatal prostate cancer of 19%. A meta study found that consumption of higher amounts of plant-based foods may be associated with decreased prostate cancer risk, and consumption of higher amounts of dairy products may be associated with increased prostate cancer risk. In a prospective cohort study of men with nonmetastatic prostate cancer, a higher plant-based diet index was associated with better scores for sexual function, urinary irritation/obstruction, urinary incontinence, and hormonal/vitality. Finally, a significant association between increased consumption of a healthy plant-based diet and lower PSA levels has been demonstrated.

While more research is needed, since many patients are placed on a passive watchful waiting protocol, adding a plant- based diet can transform the protocol to active treatment. A plant-based diet has the significant advantage of having no contraindications or adverse reactions. It deserves a place in the prevention and treatment of prostate cancer.

Keywords: Gleason score; Plant-based diet; Prostate cancer; PSA level; Vegan

Introduction

Prostate cancer remains one of the leading causes of cancer-related deaths [1] and currently the second most common male malignancy worldwide [2]. Better prevention and improved treatment remain an urgent need. Since we wrote our article “A Plant-Based Diet Prevents and Treats Prostate Cancer” in your journal, Cancer Therapy & Oncology, [3] research has continued to show that a plant-based diet can help prevent prostate cancer and treat it when it has a Gleason score less than 7. In a longitudinal observational cohort study, published in 2024, men with biopsy-proven nonmetastatic prostate cancer (stage less than T3a) scoring in the highest vs lowest quintile of PDI (Plant-Based Diet Index), which measures the amount of plant foods in the overall diet, had a 47% lower risk of progression [4].

In a 2022 prospective cohort study of men in the Health Professionals Follow-Up Study, greater overall plant food consumption was associated with a significantly lower risk of fatal prostate cancer of 19%. In men aged less than 65, a higher plant-based diet index was associated with a 16% lower risk of advanced, lethal, and fatal prostate cancer. Moreover, greater consumption of a healthful plant-based diet, a plant based diet with a lower amount of foods often designated junk foods, resulted in a 44% decreased risk of lethal prostate cancer for those aged less than 65 [5].

Studies of the vegan diet have consistently showed favorable associations with risk and/or outcomes. A 2019 meta study found that consumption of higher amounts of plant-based foods may be associated with decreased prostate cancer risk, and consumption of higher amounts of dairy products may be associated with increased prostate cancer risk. It also found that vegan diets had a 36% lower hazard ratio [6]. In a 2024 prospective cohort study of men with nonmetastatic prostate cancer, a higher plant-based diet index was associated with better scores for sexual function, urinary irritation/obstruction, urinary incontinence, and hormonal/vitality [7]. There is a significant association between increased consumption of a healthy plant-based diet and lower PSA levels. In 2021, men who followed a healthy plant-based diet were found to have a 53% decreased probability of having an elevated PSA [8]. While we welcome new research that confirms the epidemiology in our article, more interventional studies are needed to confirm the efficacy of interventional studies already done. More research is also needed to confirm the pathogenic factors already identified in animal derived foods. In the meantime, since many patients are placed on a passive watchful waiting protocol, adding a plant-based diet can transform the protocol to active treatment. A plant-based diet has the significant advantage of having no contraindications or adverse reactions. It deserves a place in the prevention and treatment of prostate cancer.

Conflict of Interest

The authors state that there are no conflicts of interest.

References

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