Plain language summary
Ulcerative Colitis (UC) is a chronic debilitating inflammatory bowel disease that may need lifetime management. Dietary management of UC by eliminating food antigens that may be causing a delayed immune response is one of the approaches used widely to manage the disease. Food intolerance, mediated by immunoglobulin G antibodies in response to food antigens that are otherwise harmless, could be one cause of UC. Low levels of digestive enzymes may result in poor digestion of glucose, amino acids, and glycerol, followed by an immune reaction that leads to food sensitivities. Ninety-seven UC patients were enrolled in this open-label, stratified, prospective, randomised controlled trial to evaluate the effect of an elimination diet versus a sham diet (a normal healthy diet). Following an IgG-specific exclusion diet for six months resulted in the alleviation of UC symptoms and an improvement in health-related quality of life. Further studies are needed to confirm the effectiveness of the exclusion diet since the intervention group did not show a significant reduction in IgG antibody levels. These results can be used by healthcare professionals to understand the potential role of exclusion diets in the management of UC.
BACKGROUND Most patients with ulcerative colitis (UC) rely predominantly on medication for disease control. Diet interventions can reduce pharmaceutical expenditures and prolong remission. We designed a prospective study to evaluate whether an immunoglobulin G (IgG)-guided exclusion diet would improve symptoms and quality of life (QoL) in patients with UC. METHODS The 6-month diet intervention included 97 patients with UC, who were randomly divided into an intervention group (n = 49) and a control (n = 48) group. Individual diet plans were created for the intervention group according to IgG titers; the control group ate a healthy diet as normal. Observational indices included disease activity, extraintestinal manifestations, nutritional status, and QoL. Relationships between food-specific IgG antibodies and these indices were also analyzed. RESULTS At baseline, there were no significant differences between the groups. Food-specific IgG antibodies were detected in 70.10% of participants. After intervention, the Mayo score was significantly lower in the intervention group than in the control group (2.41 ± 0.89 vs 3.52 ± 1.15, P < 0.05). The number of patients with extraintestinal manifestations decreased from 7 to 2 in the intervention group and from 6 to 5 in the control group. As for nutritive indices, the intervention group had higher mean body mass index and albumin than the control group (23.88 ± 3.31 vs 21.50 ± 6.24 kg/m2, respectively, P < 0.05; 48.05 ± 6.39 vs 45.72 ± 5.48 g/L, respectively, P < 0.05), whereas prealbumin and transferrin were not significantly different between the groups. QoL improved after food exclusion (P < 0.05). CONCLUSIONS An IgG-guided exclusion diet ameliorated UC symptoms and improved QoL. Interactions between IgG-based food intolerance and UC warrant further study.