Inflammatory bowel disease (IBD) is an irregular response of immune system accompanied with different inflammatory manifestations including alterations in cytokines. Probiotics are non-pathogenic organisms with probable effects in various conditions such as inflammation. The present study hypothesized whether oral intake of bifidobacterium and lactobacillus in form of probiotic yogurt may represent an immunomodulatory effect in IBD patients. Overally, 210 patients in remission phase and 95 healthy people were recruited. Patients were randomly divided into two groups of either 250 grams of probiotic yogurt (PI) or 250 grams of plain yogurt (PC) daily for 8 weeks. The healthy control group (HG) also received probiotic yogurt as noted. The serum levels of cytokines TNF-alpha, IL-6, IL-1 beta, IL-10 and CRP levels were measured at baseline and at termination time. A significant difference was observed between intervention groups of PI and PC with HG group (p < 0.05). After the intervention, serum levels of IL-1 beta, TNF-alpha and CRP were significantly decreased in PI group compared to their baseline values and intervention groups. The serum levels of IL-6 and IL-10 increased significantly after the intervention compared to baseline values and PC levels (all p-values < 0.05). Intestinal homeostasis is a balance between pro and anti-inflammatory responses of intestinal immunocytes and could be maintained by probiotics
