Sleep disorders have become a global issue, and discovering their causes and consequences are the focus of many research endeavors. Recent research suggests that individuals with sleep abnormalities are at greater risk of all-cause mortality and serious adverse health and economic consequences. Several studies support the associations among sleep, immune function and inflammation. We review the current research linking sleep, immune function, and gastrointestinal diseases and discuss the interdependent relationship between sleep, overall immune function with emphasis on inflammatory bowel disease, irritable bowel syndrome, gastro-esophageal reflux and colorectal cancer.