In an 11-year study, 58% of adults with type 2 diabetes who had metabolic-bariatric surgery were in remission, meaning their A1C was below 6.5% with no medicine to lower blood sugar. In the group that got medical and lifestyle care, 3% reached remission. Remission is not the same as a cure, and for some people diabetes came back.
What did the 11-year study find?
The study is called ARMMS-T2D, short for Alliance of Randomized Trials of Medicine vs. Metabolic Surgery in Type 2 Diabetes. The results were published in Diabetes Care, a journal of the American Diabetes Association, and the University of Oklahoma news release covered them on October 26, 2026.
The analysis included 262 adults with type 2 diabetes. Participants were randomly assigned: 166 to metabolic-bariatric surgery and 96 to medical and lifestyle management. Median follow-up was 11 years, and some people were followed for up to 14 years.
| Group | People analyzed | In remission at follow-up |
|---|---|---|
| Metabolic-bariatric surgery | 166 | 58% |
| Medical and lifestyle management | 96 | 3% |
In this study, remission means an A1C below 6.5% without medication to lower blood sugar.
The principal investigator, John P. Kirwan, who has led the study since it began, said: “Now we have a durable answer.”
Who was most likely to reach remission?
The study linked remission with these factors:
- fewer years living with diabetes before treatment
- not using insulin
- fewer types of blood-sugar-lowering medicine before treatment
- more weight lost in the first year after treatment
These are patterns across groups. They are not a forecast for any one person.
Who relapsed after remission?
Relapse was linked to a longer time living with diabetes and to more types of blood-sugar-lowering medicine before treatment. The Yahoo Health article reports that diabetes returned for some people who had reached remission. It lists how many people relapsed, and when, as not reported.
An earlier review points to a different factor. The 2013 review in Nature Reviews Endocrinology says weight regain is a major contributor to diabetes relapse after surgery. It also says fewer than 20% of people in initial remission stay in remission by 20 years. That review draws on other studies, not on ARMMS-T2D.
Is remission the same as a cure?
No. Diabetes is a disease in which blood glucose, also called blood sugar, is too high, and the NIDDK diabetes overview notes that over time this can cause heart disease, nerve damage, eye problems and kidney disease. Remission means the blood sugar numbers are in the study’s range without diabetes medicine.
The 2015 trial in JAMA Surgery separated two levels. Partial remission means no diabetes medicine, A1C below 6.5%, and fasting plasma glucose at or below 125 mg/dL. Complete remission means no medicine, A1C below 5.7%, and fasting plasma glucose at or below 100 mg/dL.
The 2013 review calls type 2 diabetes a progressive disorder, and says it should not be surprising that remission is not sustained for every patient. For more on the difference, read diabetes remission vs cure.
How does weight loss surgery work?
The ARMMS-T2D study groups the operations together as metabolic-bariatric surgery. The 2015 trial named two: Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding. The 2015 trial’s authors describe banding as “a less invasive, reversible, and low-risk procedure.” The 2013 review also names sleeve gastrectomy, one of three procedures in a 217-person study it describes.
The review describes gastric bypass as excluding the stomach and upper intestine from the normal flow of food, so digested nutrients reach the lower intestine earlier. It says blood sugar can improve within days of gastric bypass, before significant weight loss. It points to changes in gut hormones, bile acids and the gut microbiome as possible reasons, and says sustained weight loss also contributes substantially to health benefits. For the steps of each operation, ask your surgical team.
What did the study not report?
The Yahoo Health article lists these limits in the study report:
- complications and side effects
- longer-term burdens of surgery
- costs and insurance coverage
- ages, starting weight and dropout rates
- results for each procedure, since the operations are grouped together
- the treatment the comparison group received
- how many people relapsed, and when
Yahoo Health also notes that no revised treatment guidelines have been announced.
Surgery vs GLP-1 medicines vs intensive lifestyle care: how do they compare?
This study compared surgery with medical and lifestyle management. The study report does not say which medicines the medical group received, so the table does not compare surgery with GLP-1 medicines.
| Option | What the research found | Fit | Limits |
|---|---|---|---|
| Metabolic-bariatric surgery | ARMMS-T2D: 58% in remission at a median of 11 years. The 2015 trial of 61 adults: 40% of gastric bypass and 29% of gastric banding participants were in partial or complete remission at 3 years. | The 2013 review says surgery may be a reasonable approach for people with reasonable surgical risk who are otherwise unable to reach or sustain health goals. | Procedures are grouped together in ARMMS-T2D. The 2015 trial says the effect of these treatments on long-term micro- and macro-vascular diabetes complications is still unanswered. |
| GLP-1 medicines | Not reported separately in this study. | Not reported separately in this study. Ask your doctor where they could fit for you. | Not compared here. |
| Intensive lifestyle care | The 2015 trial: no participants in remission at 3 years in its intensive lifestyle group. | The 2013 review calls lifestyle modification and medical therapy the foundation of diabetes management. | The 2013 review says weight loss is difficult to achieve and sustain. Yahoo Health notes the ARMMS-T2D comparison group’s treatment is not specified. |
Why get weight loss surgery, and why does weight loss after surgery matter?
Surgery has often been seen as a last resort. The 2013 review says many consider it a last-resort step, partly because of surgical risks and because long-term results were uncertain. In the 2015 trial, mean percent body weight reduction at 3 years was 25.0% after gastric bypass, 15.0% after gastric banding and 5.7% with lifestyle treatment. In ARMMS-T2D, more weight lost in the first year went with a higher chance of remission.
What are the risks and side effects?
| Item | What the research says | Source |
|---|---|---|
| Operative death | 0.1% to 0.5% when performed at centers of excellence | 2013 review |
| Longer-term intestinal and nutritional complications | Vary by procedure | 2013 review |
| Infusion port replacement | One, for a malposition, in the gastric banding group in the first year | 2015 trial |
| Lean and bone mass | Significant reductions in the gastric bypass group, which the trial says “may warrant further investigation” | 2015 trial |
The 2013 review says surgery may be a reasonable approach for people with reasonable surgical risk. Complications were not reported in the ARMMS-T2D study report, so ask your surgical team about the risks for your own situation.
How much does weight loss surgery cost?
Yahoo Health lists costs and insurance coverage among the things the study report does not give, so this study cannot tell you a price. Ask the surgical team for an itemized estimate, and ask your insurer which parts it covers before you schedule anything.
Does surgery affect survival too?
A 2021 meta-analysis in The Lancet pooled 174,772 people. Most of its inputs were matched cohort studies, and only one was a prospective controlled trial. It found metabolic-bariatric surgery was associated with a lower rate of death than usual care, and that the association was much stronger for people with diabetes at the start.
Questions to bring to your doctor
- Based on how long I have had diabetes and my current medicines, where do I fall in the patterns this study describes?
- Which operation would you offer, and what diabetes results do you expect for that procedure?
- What A1C and blood sugar numbers would count as remission for me?
- What monitoring would I need after surgery, and for how long?
- Which complications should I watch for, and how are they handled?
- What will this cost, and what will my insurer cover?
- How would GLP-1 medicines or an intensive lifestyle program compare for my situation?
- What weight loss should I expect in the first year, and how will we track it?
- What happens to loose skin after large weight loss, and is any treatment covered?
Write these questions down and bring your weight and medicine history. The weight loss treatment tracker explains what to record and why it helps at a visit.
By the Primary Care Evidence Guide Team