Feasibility and Acceptibility of a Multi-site Trial of Time Restircted Eating During Chemotheraply for Breast Cancer.

Inclusion Criteria: * Age 25-99 at time of consent * English language or Spanish language (based on availability of lab interpreters) * ECOG 0 or 1 * Breast cancer to meet histologically confirmed Stage I-III or Stage IV with Medical Oncology approval. * Demonstrates adequate organ function (absolute neutrophil count ≥ 1,500/μL). * All screening labs to be obtained within 30 days prior to registration. * Able to provide written informed consent and HIPAA authorization for release of personal health information, via an approved UIC Institutional Review Board (IRB) informed consent form and HIPAA authorization. * Women of childbearing potential must not be pregnant or breast-feeding. A negative serum or urine pregnancy test is required per institutional practice guidelines. * As determined at the discretion of the enrolling physician or protocol designee, ability of the subject to understand and comply with study procedures for the entire length of the study. Exclusion Criteria: * Women with type 1 or insulin dependent type 2 diabetes * Women with BMI \> 45kg/m2 and \< 18.5 kg/m2 * Women who are pregnant or nursing. A negative serum or urine pregnancy test is required per institutional practice guidelines. * Shift workers * Women with a history of eating disorders * Enrolled participants with a significant weight loss or weight gain within 3 months of the study (weight gain or loss \>4kg) * Uncontrolled HIV/AIDS or active viral hepatitis * Any prior malignancy \<5 years, che…