Metabolic and Inflammatory Response to a Whole Food Plant-Based Diet in Overweight/Obese Men with Prostate Cancer Receiving Androgen Deprivation Therapy: A Phase II Randomized Study

Androgen deprivation therapy (ADT) is the cornerstone of treatment for advanced prostate cancer. However, ADT can be associated with significant adverse effects including weight gain, accumulation of body fat, insulin resistance, and an elevated risk of diabetes and cardiovascular death. Dr. Nanus and team hypothesize that a whole-food plant-based diet (WFPBD) and behavior intervention will promote weight loss and reduce adiposity in overweight/obese prostate cancer patients on ADT as well as decrease risk of ADT-associated adverse effects including metabolic disorders and cardiovascular mortality. In this project, the team will conduct a randomized controlled trial of a two-phase WFPBD intervention for obese or overweight prostate cancer patients on ADT. Study participants assigned to the WFPBD group will receive home-delivered WFPBD meals for 4 weeks along with nutritional counseling, followed by 22 weeks of patients preparing their own WFPBD meals with continued support from study dieticians. Subjects in the control arm of this study will receive standard of care nutritional counseling. The team will investigate whether the WFPBD intervention promotes weight loss and/or reduces body fat composition, compared to standard of care nutritional counseling. Compliance to the dietary intervention will be estimated by measuring blood carotenoid levels. The team will also assess quality of life using standard questionnaires. In addition, the team will investigate whether the WFPBD intervention improves biomarkers of inflammation (IL-6, hsCRP), metabolic disorders such as diabetes (hemoglobin A1c, fasting insulin/glucose), cardiovascular risk (LDL cholesterol, HDL cholesterol, triglycerides), or changes the composition of the gastrointestinal microbiome, using blood, urine, and fecal samples collected from patients at various times over the study. In depth studies will also be done to determine whether the WFPBD intervention changes metabolism by measuring a panel of metabolites. If successful, this study will establish a practical lifestyle intervention that will attenuate detrimental health effects associated with ADT, particularly among patients who are overweight or obese.