Introduction: Gut microbiota plays a crucial role in the improvement of metabolism and host homeostasis. The modulation of some gut microbiota species, as Akkermansia muciniphila, by some dietary supplements, including probiotics and prebiotics, has been proved to act positively on glucose control. Akkermansia muciniphila significantly increases in the human gut microbiota after supplementation with inulin. Aim of the study is to evaluate if the supplementation with inulin could have some benefit on glucose control. Materials and methods: Adults with T1DM, on continuous subcutaneous insulin infusion, were randomized 1:1, stratified by age and sex, to standard of care (SoC) + inulin 6g twice a day for 3 months or standard of care. Before and 3 months after randomization following parameters were evaluated: body weight, total daily insulin dose, glycated haemoglobin (HbA1c), continuous glucose monitoring (CGM) metrics. The primary endpoint was the change in body weight after 3 months. Akkermansia muciniphila was also assessed in foecal samples of a subset of participants through real time PCR. Results: 49 subjects were enrolled in the study, age 46 [37-53] years, 30 females (61%), duration of disease 20 [11-27] years, HbA1c 64 [59-72] mmol/mol. 24 subjects were randomized to inulin + SoC and 25 subjects were randomized to SoC. After 3 months inulin + SoC was associated with slight decrease in body weight (inulin + SoC median change -2 [-3; 0] Kg vs SoC 0 [-1; 1] kg, p=0.029) and in insulin total daily dose (inulin + SoC median change -1.5 [-3.1; 0] UI vs SoC 0.6 [0; 1.7] UI, p=0.010). Although not significant, inulin was associated with higher reduction of HbA1c (inulin + SoC median change -4.5[ -7; -3]% vs SoC -2 [-3.5; 0]%, p=0.07). No significant variation of time in range, coefficient of variation and GMI were detected. In some of inulin group Akkermansia abundance has been detected. Conclusion: Inulin, a probiotic stimalutating Akkermansia muciniphila and positively modifying gut microbiota, is associated with reduction of body weight and of insulin doses. Not significant effect were detected on HbA1c and CGM metrics.