The etiology of inflammatory bowel disease is unclear, and the role played by anxiety and depression is highly controversial. Anxiety and depression in patients with inflammatory bowel disease could be secondary to disabling symptoms, but the interaction between physical morbidity and psychologic illness in these subjects has not been sufficiently investigated. Patients with inflammatory bowel disease are nevertheless frequently undernourished, but there are no studies on the association between anxiety and depression and malnutrition. This study was designed to characterize anxiety and depression in subjects affected by inflammatory bowel disease and to establish the influence of physical morbidity and/or nutritional status on psychologic disorders. Seventy-nine consecutive patients, 43 with Crohn's disease (CD) and 36 with ulcerative colitis (UC), were enrolled in the study. An index of the disease activity and physical morbidity was obtained by the simplified Crohn's Disease Activity Index and Truelove-Witts criteria and using the Clinical Rating Scale. Thirty-six healthy volunteers were studied as controls. All the subjects were given the State and Trait Anxiety Inventory (STAI) test and the Zung self-rating Depression Scale. The percentage of subjects with state anxiety was significantly higher in the CD (P < 0.001) and UC (P<0.001) groups than in control subjects. There was no significant difference in trait anxiety among groups. The percentage of subjects with depression was significantly higher in the CD (P<0.05) and UC (P<0.05) groups than in control subjects. State anxiety and depression were significantly associated with physical morbidity and correlated with malnutrition in CD and UC patients. Anxiety and depression in patients with inflammatory bowel disease could be reactive to the disabling symptoms and to malnutrition. As measured with the STAI, personality trait of anxiety does not seem to play an important role in inflammatory bowel disease.