Method of using abscisic acid to treat diseases and disorders

Methods and compositions for treating inflammatory bowel disease, gastrointestinal inflammation and maintaining normal gut health are described. These methods of the invention involve the administration of abscisic acid in amounts sufficient to alter the expression or activity of PPAR gamma in a cell. Also described are methods for suppressing the expression of cellular adhesion molecules in the gut and methods for increasing CTLA-4 expression on CD4+ T cells through administration of abscisic acid.