Intermittent Fasting Using a Fasting-Mimicking Diet to Improve Prostate Cancer Control and Metabolic Outcomes

Inclusion Criteria:

• Metastatic castrate sensitive prostate adenocarcinoma (Adenocarcinoma prostatehistologically confirmed by biopsy AND Metastatic disease confirmed biopsy, or MRIscan)

• Men receiving or planning to start first-line intensified ADT (within 30 days ofregistration) with abiraterone, apalutamide, enzalutamide, or darolutamide with orwithout current or prior chemotherapy

• Reads, writes, and understands English or Spanish and has telephone access forremote contact with the study dietitian.

• Written informed consent obtained from subject and ability for subject to complywith the requirements of the study.

Exclusion Criteria:

• Allergies to any ingredients listed on the Xentigen Ingredient List

• Men with diabetes who are not on stable doses of antihyperglycemic medication for atleast 6 months and without physician consent that they may safely holdantihyperglycemic medication during the 5 days of FMD

• Regularly practicing a fasting diet that in the opinion of the study physician wouldimpact study participation

• Significant co-morbidities (i.e., cardiac, pulmonary, liver disease, ongoingalcohol/drug abuse) that in the opinion of the study physician would precludeenrollment in this study.

• Body Mass Index (BMI) <20kg/m2

• Men actively trying to lose weight OR on weight loss medications (including but notlimited to Contrave, Saxenda, Xenical) or planning to receive weight loss surgery inthe next six months

• Self-reported weight loss ≥ 10% in the last 6 months