BACKGROUND Diet is thought to have an important role in the etiopathogenesis of Crohn's disease. In the other hand, Crohn's disease is frequently associated with nutritional deficiencies probably as result of disease activity and poor oral intake. OBJECTIVE To investigate the dietary intake in patients with Crohn's disease in comparison with matched population controls and to assess the correlation between the results of the dietary enquete, nutritional status and disease activity. METHODS We conducted a prospective case control study in patients with Crohn's disease and matched controls. All subjects were evaluated in respect of dietary intake (based on "NUTISTAR" logiciel) and nutritional status. RESULTS We studied 23 patients and 23 controls. There was no statistical difference between patients and controls according to the proportion of carbohydrates, fat and protein intakes. Energy intakes were significantly lower in patients with Crohn's disease (1991 + 678 kcal/j) compared to controls (2537 + 345 kcal/j) (p=0.007) ; and in active disease (1353 + 308 kcal/j) compared to inactive disease patients (2481 + 415 kcal/j) (p<0.0001). In Crohn's disease patients, correlation study showed that energy intakes were correlated with CDAI (p<0.0001 ; r = - 0.74) and BMI (p=0.03 ; r = 0.45). CONCLUSIONS In Crohn's disease, an inadequate dietary intake is correlated with nutritional status and disease activity.