Over the past 5 years, there has been a rapid resurgence of interest in vitamin D outside of its traditional role in metabolic bone disease. Some nontraditional roles ascribed to vitamin D include anti-inflammatory and immune-modulating effects. These effects have led to possible implications in the pathophysiology of immune-mediated diseases including multiple sclerosis and inflammatory bowel disease (IBD). In addition, vitamin D insufficiency has been linked to higher rates of cancers including colon, prostate and breast cancers. Given these diverse associations of vitamin D and disease states, this review describes recent advances with regard to vitamin D and gastrointestinal diseases, in particular IBD and colorectal cancer.