The importance of the host inflammatory response, as a central pathological feature of cystic fibrosis, is well recognized. Additionally, hyperglycemia can induce an immune response and consecutively may exacerbate symptoms of this disease. Hence, adherence to a low glycemic index diet, through normalizing blood glucose levels, may reduce inflammation in patients with this disease. This study aimed to compare effects of a low glycemic index/high-fat, high-calorie diet and routine high-fat, high-calorie diet on inflammatory biomarkers in patients with cystic fibrosis. In this randomized clinical trial, 44 children and adolescents with cystic fibrosis were randomly assigned to receive for three months either a high-fat, high-calorie diet (n = 22) or a low glycemic index/high-fat, high-calorie diet (n = 22) with similar calorie and macronutrients composition to the control diet. Patients in first arm were allowed to use all sources of carbohydrates with different glycemic indices, whereas those in another arm consumed carbohydrates from low glycemic index sources. Serum levels of the pro-inflammatory cytokines IL-6, IL-17A, and IFNg, and the antiinflammatory cytokine IL-10 were measured at baseline and after the end of the trial. There were significant differences between groups for IL-6 (P = 0.02) and IL-17 (P = 0.01), in favor of the low glycemic diet, but no between-group differences were detected in IL-10 and IFN-γ. Although serum levels of IL-17 were reduced in both the groups as compared with the baseline values, this reduction was only significant in the group assigned to the low glycemic diet (P= 0.007), In addition, IL-6 serum levels decreased and those of IL-10 increased significantly as compared with the baseline values in the low glycemic diet (P= 0.01). It seems that adherence to a low glycemic index/high-fat, high-calorie diet for three months can improve some inflammatory biomarkers in children and adolescents with cystic fibrosis compared with the high-fat, high-calorie diet.

宿主炎症反应作为囊性纤维化的核心病理特征，其重要性已得到广泛认可。此外，高血糖可以诱发免疫反应，并可能连续加剧这种疾病的症状。因此，通过使血糖水平正常化，坚持低血糖指数饮食，可以减少患有这种疾病的患者的炎症。本研究旨在比较低血糖指数/高脂肪、高热量饮食和常规高脂肪、高热量饮食对囊性纤维化患者炎症生物标志物的影响。在这项随机临床试验中，44 名患有囊性纤维化的儿童和青少年被随机分配接受三个月的高脂肪、高热量饮食 (n = 22) 或低血糖指数/高脂肪、高热量饮食(n = 22) 与对照饮食具有相似的热量和大量营养素成分。第一组的患者被允许使用具有不同血糖指数的所有碳水化合物来源，而另一组的患者则食用低血糖指数来源的碳水化合物。在基线和试验结束后测量促炎细胞因子 IL-6、IL-17A 和 IFNg 以及抗炎细胞因子 IL-10 的血清水平。 IL-6 (P = 0.02) 和 IL-17 (P = 0.01) 组间存在显着差异，有利于低血糖饮食，但 IL-10 和 IFN-γ 未检测到组间差异。尽管与基线值相比，两组的 IL-17 血清水平均有所降低，但这种降低仅在低血糖饮食组中显着（P = 0.007）。此外，IL-6 血清水平降低，并且与低血糖饮食的基线值相比，IL-10 显着升高（P=0.01）。与高脂肪、高热量饮食相比，坚持低血糖指数/高脂肪、高热量饮食三个月似乎可以改善囊性纤维化儿童和青少年的一些炎症生物标志物。