Immunonutrition to Reduce Toxicities in Non-Small Cell Lung Cancer

Inclusion Criteria: * Patients will be recruited from the Moffitt Cancer Center Thoracic Oncology Outpatient Clinic when identified by a thoracic oncologist that the patient will undergo all of their chemoradiotherapy at Moffitt. * Men and women ≥18 years of age. * Diagnosed with unresectable stage IIIA or IIIB non-small cell lung cancer. * Patients plan to undergo all cancer treatment at Moffitt Cancer Center with definitive concurrent chemotherapy and radiotherapy. * No prior treatment of NSCLC. * Able to provide informed consent. * Performance status 0, 1 or 2. * Life expectancy \>3 months. * No esophagitis within 90 days. Exclusion Criteria: * Mental incompetence or chronic psychiatric disease. * Incarcerated individuals. * Use of antibiotics or probiotic supplements within one month of chemoradiotherapy. * Allergy to any of the components of Impact® Advanced Recovery or Boost® High Protein. * Pregnant female or breast-feeding. Any female patient \<45 years old not using appropriate contraceptive measures during the treatment. * Sepsis or active infection. * Chronic renal failure stage IV (requiring protein restriction) or stage V requiring dialysis. * Malnutrition defined as BMI \<16. * Inflammatory bowel disease (ulcerative colitis or Crohn's disease). * Severe hepatic dysfunction (baseline prothrombin time off any anticoagulation of international normalized ratio (INR) \>1.8). * Significant digestive disease with nausea, vomiting or diarrhea, NCI Grade \>1. * Use of IL-6 inhibitors (tocilizumab or siltuximab) within last 6 months.