PRIMARY OBJECTIVES:~I. To test the hypothesis that time-restricted eating during radiation therapy (RT) or chemotherapy and radiation therapy (chemoRT) could reduce the level of accumulated double stranded deoxyribonucleic acid (dsDNA) damage in peripheral blood mononuclear cells (PBMCs) over the course of RT as measured by the gH2ax assay.~II. To examine if time-restricted eating during RT is associated with reduced toxicity as measured by clinician reported adverse events using Common Terminology Criteria for Adverse Events (CTCAE) version (v)5.0, improved patient quality of life as measured by European Organization for the Research and Treatment of Cancer Quality of Life (EORTC-PR25) (prostate cancer) and EORTC-CR29 (rectal cancer), reduced dsDNA damage as measured by assay for 8-oxo-dG and persistent DNA damage in shed epithelial cells from the urinary tract, reduced oxidative DNA damage as measured by reduced cumulative 8-oxoguanine DNA adducts, impacts the diversity of microbiome in relation and development of radiation induced microbiota dysbiosis and metabolic impact using liquid chromatography mass spectrometry (LC/MS) metabolomic analysis and correlative serological markers including IGF-1.0).~OUTLINE: Patients are randomized to 1 of 2 arms.~ARM I: Patients undergo time-restricted eating Monday through Friday only of each week on study during standard RT or chemoRT. Patients also undergo collection of blood throughout the trial.~ARM II: Patients receive nutritional counseling on study. Patients also undergo collection of blood throughout the trial.
This phase II trial studies how well time-restricted eating works in reducing side effects of radiation or chemoradiation side effects when compared to nutritional counseling among patients with prostate, cervical, and rectal cancers. Time-restricted eating, also called short term fasting or intermittent fasting, is an eating plan that alternates between not eating food (fasting) and non-fasting periods. Nutritional counseling involves being asked to follow a healthy, balanced diet that includes instructions on what kinds of food are better tolerated during radiation and chemoradiation therapy. This trial may help researchers determine if certain diets may improve the anti-cancer effects of radiation therapy and reduce the side-effects of this treatment. If successful, these diets may be integrated into the future treatment of prostate, cervical, and rectal cancers.