# Does Semaglutide Help Type 1 Diabetes? What Two Small Trials Found | This GLP In ADJUST-T1D, semaglutide cut total daily insulin 22.6% in type 1 diabetes. A crossover trial raised time in range 4.8 points without more hypoglycemia. Publisher: This GLP Editorial Team Canonical: https://thisglp.com/research/semaglutide-in-type-1-diabetes Updated: 2026-09-18 Published: 2026-09-17 [← Research](https://thisglp.com/research) Evidence # Does Semaglutide Help Type 1 Diabetes? What Two Small Trials Found Total daily insulin fell 22.6% and time in range rose 4.8 points without more hypoglycemia. It is off-label, both trials were small, and two people developed ketosis at normal glucose. [This GLP Editorial Team](https://thisglp.com/about)September 20267 min readUpdated September 2026 Where the insulin reduction came from, units per day · week 4 · 13.4 total · week 26 · 21.9 · the drug itself · the weight loss · The drug’s own contribution barely moved: 11.1 then 11.4. · Everything added between weeks 4 and 26 came from weight. **Research, not medical advice.** This GLP is independent and educational. Nothing here is a substitute for individualized care from a licensed clinician, and reading it creates no doctor–patient relationship. Talk to your own provider before starting, stopping, or changing any medication, peptide, or therapy. See our [methodology](https://thisglp.com/methodology) and [terms](https://thisglp.com/terms). ## Key takeaways - Type 1 diabetes is not an approved indication for any GLP-1 drug, and both trials below ran under close supervision. - Adding semaglutide to automated insulin delivery cut total daily insulin by 22.6%, driven more by bolus (-30.5%) than basal (-15.6%) doses. - Early on, the reduction was mostly a direct drug effect rather than a consequence of weight loss: 83% at week four, falling to 52% by week 26. - A separate crossover trial raised time in range by 4.8 percentage points without more hypoglycemia — but recorded two episodes of euglycemic ketosis. Two small randomized trials have now tested a GLP-1 drug alongside modern insulin therapy in type 1 diabetes, and both found something worth knowing. Neither makes it an approved treatment, and the reason to read them carefully is that the changes they describe involve taking insulin away from people who cannot live without it. ## What happened to the insulin A post hoc analysis of the ADJUST-T1D trial followed adults with type 1 diabetes and obesity who were using automated insulin delivery systems, and who took semaglutide 1 mg weekly or placebo for 26 weeks [\[1\]](https://thisglp.com/research/semaglutide-in-type-1-diabetes#ref-1). Total daily insulin fell 22.6%, with an interval running from 28.3 to 17.0 — a change of the kind this site sizes carefully in [what each dose step took away](https://thisglp.com/research/each-dose-step-took-insulin-away). The reduction was not spread evenly across the two kinds of insulin a person takes. Bolus doses, the ones covering meals, fell 30.5%, while basal doses covering the background requirement fell 15.6%. The share of the total that was basal therefore rose from 0.56 to 0.62, and insulin per kilogram per day fell from 0.72 to 0.60. Daily carbohydrate intake fell from 137 g to 107 g over the same period. Read the units, not the percentages At week four the drug’s direct effect accounted for 11.1 units a day and weight loss for 2.3. At week 26 the direct effect accounted for 11.4 units and weight loss for 10.5. The split moved from 83/17 to 52/48, but the drug’s own contribution barely changed in absolute terms — what grew was the weight side. A reader given only the percentages would conclude the drug effect faded, and it did not. This site separates the two the same way in [the liver repair that was not the weight](https://thisglp.com/research/liver-repair-that-was-not-the-weight). ## What happened to the glucose A separate double-blind crossover trial gave weekly semaglutide or placebo to people using automated insulin delivery, randomizing 28 participants of whom 24 completed [\[2\]](https://thisglp.com/research/semaglutide-in-type-1-diabetes#ref-2). Time in the target glucose range rose by a mean 4.8 percentage points against placebo. Semaglutide added to automated insulin delivery, against placebo. | Outcome | Result | Significance | | --- | --- | --- | | Time in target range | +4.8 points (SD 7.6) | P = 0.006 | | Time below 3.9 mmol/L | no increase | P = 0.19 | | Time below 3.0 mmol/L | no increase | P = 0.65 | Semaglutide added to automated insulin delivery, against placebo. Double-blind randomized crossover trial, 28 randomized Improving time in range without buying it back in low readings is the combination that matters in type 1 diabetes, because a drug that flattens glucose by pushing people toward hypoglycemia has not helped them at all. ## The safety signal a type 1 reader needs Two episodes of ketosis at normal glucose No diabetic ketoacidosis and no severe hypoglycemia occurred during any intervention. But the crossover trial recorded two episodes of recurrent euglycemic ketosis without acidosis during semaglutide use. Ketosis while blood glucose looks normal is the version that is easy to miss, because the number on the meter is reassuring while the problem is developing — and it is a recognized hazard when insulin comes down. This site covered the broader picture in [ketoacidosis without diabetes](https://thisglp.com/research/can-a-glp1-cause-ketoacidosis). ## How far this goes Not far, and the numbers are the reason. Twenty-eight people were randomized in one trial, and the other is a post hoc analysis of a larger but still modest study. Neither is the scale at which a safety signal separates from chance, or at which subgroups become visible. Both trials also enrolled people already using automated insulin delivery, which is a system that adjusts doses continuously and catches drift that a fixed regimen would not. Whether the same reductions would be safe on injections and finger-sticks is untested, and it is the setting most people with type 1 diabetes are actually in. ## What happened when it stopped The ADJUST-T1D team kept continuous glucose monitors on after the 26-week trial ended and followed people for a 12-week extension [\[3\]](https://thisglp.com/research/semaglutide-in-type-1-diabetes#ref-3). Sixteen had come off semaglutide, and 22 had been on placebo and started no GLP-1 drug afterwards, which is a small group on either side. Time in range fell by a median 3.6 percentage points in the people who stopped, against a 1.5-point rise in the placebo group. Glucose also swung more: the standard deviation rose 6.0 mg/dL against 1.2. Time above range crept up but lost significance after adjustment, and hypoglycemia measures did not differ between the groups. The authors read it as benefits that may not fully survive withdrawal, which is the story told at more length in [what happened when type 1 patients stopped](https://thisglp.com/research/type-1-diabetes-stopping-semaglutide). Nothing here is a reason to change an insulin dose, which is a decision that belongs to the clinician managing it. ## Frequently asked Is semaglutide approved for type 1 diabetes? No. Type 1 diabetes is not an approved indication for any GLP-1 drug, and both trials described here ran off-label under close supervision. How much did insulin needs fall? Total daily insulin fell 22.6% over 26 weeks, with bolus doses down 30.5% and basal doses down 15.6%. Insulin per kilogram per day went from 0.72 to 0.60 units. Was that just the weight loss? Not early on. At week four, 83% of the reduction was attributed to a direct drug effect and 17% to weight loss. By week 26 the two contributions were about equal in units per day. Did glucose control improve? Time in the target range rose by 4.8 percentage points against placebo, without more time spent below 3.9 or 3.0 mmol/L. What happens to glucose after stopping semaglutide in type 1 diabetes? In a 12-week extension of ADJUST-T1D, time in range fell a median 3.6 percentage points in 16 people who stopped, against a 1.5-point rise in 22 who had been on placebo, and glucose variability rose. What is the main safety concern? Two episodes of recurrent euglycemic ketosis without acidosis occurred during semaglutide use. Ketosis while glucose reads normal is easy to miss, and it is a recognized hazard when insulin doses come down. ## Sources 1. \[1\] Karakus KE, Akturk HK, Kruger D, Ahmann A, Bharvaga A, Langel CR (2026). Effect of Semaglutide on Insulin Dose Reduction in Adults With Type 1 Diabetes and Obesity Using Automated Insulin Delivery Systems: ADJUST-T1D Post Hoc Analysis Diabetes Care. [PMID 41429002](https://pubmed.ncbi.nlm.nih.gov/41429002/) 2. \[2\] Pasqua MR, Tsoukas MA, Kobayati A, Aboznadah W, Jafar A, Haidar A (2025). Subcutaneous weekly semaglutide with automated insulin delivery in type 1 diabetes: a double-blind, randomized, crossover trial Nature Medicine. [PMID 39794615](https://pubmed.ncbi.nlm.nih.gov/39794615/) 3. \[3\] Montaser E, et al. (2026). Glycaemic Changes After Semaglutide Discontinuation in Adults With Type 1 Diabetes Using Automated Insulin Delivery: Analysis of the ADJUST-T1D Extension Study Diabetes, Obesity and Metabolism. [PMID 42675550](https://pubmed.ncbi.nlm.nih.gov/42675550/) ## Where to get it ### Best GLP-1 injections Every injectable seller we can verify, with the price each one publishes and an honest read of what the trials measured. [Compare providers →](https://thisglp.com/best/compounded-semaglutide) ## More in Evidence - [ 150 minutes · Weekly activity goal · 2 days · Muscle strengthening · Adapt · Symptoms and ability ### Exercise on Ozempic: Building Strength Without Ignoring Symptoms ](https://thisglp.com/research/exercise-on-ozempic) - [ STEP 1, semaglutide 2.4 mg vs placebo, % change at 68 weeks · LDL cholesterol · −2.5% vs +1.3% · Total cholesterol · −3.3% vs +0.1% · HDL cholesterol · +5.2% vs +1.4% · Triglycerides · −21.9% vs −7.3% · Wegovy label, Table 13. Adults without diabetes. Ozempic doses are lower. ### Does Ozempic Lower Cholesterol? What the Lipid Results in the Trials Show ](https://thisglp.com/research/does-ozempic-lower-cholesterol) - [ Weight loss, tirzepatide against semaglutide · chart review, 12 mo · −16.6% · −13.4% · matched cohort, 2 yr · −14.7% · −10.8% · Randomized, SURMOUNT-5: 20.2% against 13.7% at 72 weeks. ### Tirzepatide vs Semaglutide: Which Works Better for Weight Loss? ](https://thisglp.com/research/tirzepatide-vs-semaglutide-which-works-better)