Caloric Restriction and Activity for B-cell Leukemia

Inclusion Criteria: * Patients must be ≥ 7.0 and \<26.0 years of age. * Patients must have a diagnosis of de novo B-ALL * Patients must have a M3 marrow (\>25% blasts by morphology) or at least 1,000/µL circulating leukemia cells in PB confirmed by Flow Cytometry (or other convincing evidence of a B-ALL diagnosis not meeting above criteria following central review by the Study Hematopathologist and Study Chair or Vice-Chair). * The treatment regimen must be the first treatment attempt for B-ALL- * Must be a multi-agent induction regimen inclusive of vincristine, glucocorticoid, pegaspargase/calaspargase, and daunorubicin or doxorubicin and with a planned duration \<35 days. * Organ function must meet that required for initiation of chemotherapy * Patients at diagnosis must meet Karnofsky \> 50% for patients \> 16 years of age and Lansky \> 50% for patients ≤ 16 years of age (or be expected to recover prior to Day 8) . * If the patient is a female of childbearing potential, a negative urine or serum pregnancy test is required within two weeks prior to enrollment. Exclusion Criteria: * Patient will be excluded if they are underweight at time of enrollment (BMI% \<5th percentile for age for patients age 10-19 years, BMI \<18.5 in patients 20-29 years). * Patients with Down syndrome or a DNA fragility syndrome (such as Fanconi anemia, Bloom syndrome) will be excluded. * Patient receiving a SJCRH-style "Total Therapy" regimen will be excluded. * Patients receiving anti-CD20 monoclonal antibody therapy during induction therapy. * Patients will be excluded if they received treatment for a previous malignancy. * Patient will be excluded if they are pregnant. * Patient will be excluded if they have a pre-diagnosis requirement for enteral or parenteral supplementation . * Patient will be excluded due to inability to perform the intervention (e.g., specific nutritional needs, severe developmental delay, paraplegia) * Patients will be excluded if they have significant concurrent disease, illness, psychiatric disorder or social issue that would compromise patient safety or compliance with the protocol treatment or procedures, interfere with consent, study participation, follow up, or interpretation of study results