Crohn's disease is associated with a number of signs and symptoms. People experience abdominal pain, diarrhea, bleeding, fistulas, perianal disease, malabsorption, and others. Generally speaking, a high calorie, high-protein diet is the best diet for patients with Crohn's disease. The disease usually progresses as a series of remissions punctuated by exacerbations or flares. One major difference between ulcerative colitis and Crohn's disease is that ulcerative colitis occurs solely in the large intestine, while Crohn's disease can occur anywhere from mouth to anus.