Background. Crohn's disease (CD) and ulcerative colitis (UC), collectively known as inflammatory bowel disease (IBD), are chronic illnesses that affect predominately the gastrointestinal tract. The pathogenesis and etiology remain unclear but the importance of environmental factors, in particular diet, is evidenced by the increased incidence rates of the recent decades that genetic inheritance cannot account for. In particular, the quantity of fatty acid consumption has been consistently linked with IBD risk. While several studies have investigated the connections between diet, etiology, signs and symptoms associated with IBD, very few have explored the relationship between disease state and specific fatty acid intake in the pediatric IBD population. Methods. In this cross-sectional study, 100 pediatric patients from Cincinnati Children's Hospital and the Hospital for Sick Children in Toronto with diagnosed IBD (73 with Crohn's disease (CD) and 27 with ulcerative colitis (UC)) were included. Three-day diet records were collected from the patients for the assessment of their dietary intake. The abbreviated Pediatric Crohn's Disease Activity Index (PCDAI), the abbreviated Ulcerative Colitis Activity Index (PUCAI), and markers of inflammation (lipopolysaccharide binding protein (LBP) and S100A12) were used to assess disease severity. A logistic regression analysis was carried out to correlate disease severity with the dietary intake of specific fatty acids and total dietary intake. Results. Total caloric, saturated fat (SFA), and monounsaturated fat (MUFA) intake were negatively associated (p<0.05) with PCDAI scores in CD alone. The individual SFAs butyric, caproic, caprylic, capric, lauric, myristic, palmitic, margaric, and stearic also were also negatively associated with disease activity scores in CD group. However, no significant associations were iii observed between the major types of fatty acids and markers of inflammation. Margaric acid was the only fatty acid significantly associated (p<0.05) with the markers of inflammation, as it was positively correlated with S100A12. Discussion. Our analysis indicates that both total fatty acid intake and total caloric intake were inversely associated with disease activity. A change in habitual dietary intake is the most likely explanation for this negatively associated trend. Relapsed patients consumed significantly lesser amounts of fatty acids and calories than patients who were in remission. The importance of this relationship should not be disregarded since pediatric IBD patients are at a high risk for growth failure, delayed puberty, anemia, osteoporosis, and other medical conditions. This study adds reason for the importance of follow-ups with nutrition professionals and gastroenterologists during remission and active states in order for pediatric IBD patients to maintain a healthy nutritional status.