Dr. Lebwohl is a graduate of Harvard College, where he majored in music. He received his MD from Columbia College of Physicians and Surgeons in 2003, and then completed his internship, residency, and chief residency in internal medicine at Columbia. He stayed at Columbia as a fellow in Digestive and Liver Disease, during which time he obtained a Masters in Patient Oriented Research from the Department of Biostatistics at the Mailman School of Public Health. He was a post-doctoral fellow in a National Cancer Institute-funded Training Program in Cancer-Related Population Sciences under the mentorship of Alfred Neugut. He joined the faculty of the Celiac Disease Center at Columbia University in 2010.

Based at the Celiac Disease Center at Columbia University, Dr. Lebwohl is collaborating with institutions in the United States and abroad in the areas of the epidemiology, patterns of care, and the natural history of celiac disease. Dr. Lebwohl's second and related research interest is quality of endoscopy, including bowel preparation prior to colonoscopy, improving the detection of colorectal adenomas, and improving the diagnostic yield of biopsy of the small intestine.

Dr. Lebwohl is the Louis and Gloria Flanzer Scholar at Columbia University Medical Center. He is the recipient of a Young Investigator Research Grant from the Celiac Disease Foundation (2019-2021). He is an associated scholar at the Karolinska Institute in Stockholm, Sweden, where he performs population-based research in celiac disease in the Department of Medical Epidemiology and Biostatistics. He currently serves as a member of the Gastrointestinal Drugs Advisory Committee of the United States Food and Drug Administration. He is heavily involved in medical education and lectures regularly to trainees on topics including celiac disease, clinical decision making, quality improvement, pseudoscience, diarrhea, the Beethoven string quartets, and colorectal cancer screening.