Patients with inflammatory bowel diseases like Crohn's disease and ulcerative colitis could benefit from marijuana use, studies suggest. University of Nottingham researchers found in 2010 that chemicals in marijuana, including THC and cannabidiol, interact with cells in the body that play an important role in gut function and immune responses. The study was published in the Journal of Pharmacology and Experimental Therapeutics. THC like compounds made by the body increase the permeability of the intestines, allowing bacteria in. The plant derived cannabinoids in marijuana block these body cannabinoids, preventing this permeability and making the intestinal cells bond together tighter. - Business Insider