Japanese study links muscle mass to T2D remission

Japanese researchers have added a new variable to the usual discussion of type 2 diabetes remission after bariatric surgery: muscle. A study published online April 29 in *Biomedical Reports* found that patients with higher skeletal muscle mass before and after laparoscopic sleeve gastrectomy were more likely to achieve remission of type 2 diabetes. The research looked at 90 patients treated at Hokkaido University Hospital between October 2016 and February 2024. At six months after surgery, the median total weight loss was 21%, median excess weight loss was 52%, and the rate of diabetes remission or improvement was 75%. ### Which patients did the researchers study? Hokkaido University Hospital surgeons and researchers analyzed 90 patients with severe obesity who underwent laparoscopic sleeve gastrectomy, or LSG, over roughly eight years. The study was retrospective, meaning the team reviewed outcomes after treatment rather than assigning patients prospectively to different interventions. Skeletal muscle mass was assessed by bioelectrical impedance analysis, a body-composition method commonly used in clinical practice. (spandidos-publications.com) The paper focused on perioperative factors tied to diabetes remission, including muscle or skeletal mass before and after surgery. LSG, the procedure studied here, is described in the paper as one of the most frequently performed bariatric operations worldwide and the most commonly performed bariatric surgical procedure in Japan. ### What did the study find beyond weight loss? (spandidos-publications.com) At six months after surgery, the remission group had significantly higher skeletal muscle mass or skeletal muscle percentage throughout the preoperative and postoperative period, according to the abstract. The authors wrote that a relationship was observed between type 2 diabetes remission after LSG and skeletal muscle mass before and after surgery. (spandidos-publications.com) Medindia’s May 20 summary of the paper said patients who achieved remission “consistently had higher skeletal muscle levels during the perioperative period.” That framing matters because it shifts attention from weight loss alone to body composition during treatment and recovery. ### Why would muscle matter in diabetes remission? The authors said skeletal muscle plays an essential role in energy metabolism and whole-body glucose homeostasis. (spandidos-publications.com) The paper notes that diabetes decreases insulin-induced glucose uptake in skeletal muscle. Medindia, citing the study, said skeletal muscle is a major site for glucose removal from the bloodstream and that muscle contraction can activate pathways that move glucose into muscle cells even without insulin stimulation. (medindia.net) That does not prove that preserving muscle causes remission in every patient, but it helps explain why patients with more muscle may have better metabolic outcomes after surgery. (spandidos-publications.com) ### Does this mean muscle matters more than the surgery itself? The study does not say that muscle replaces surgery as the main driver of remission. The operation still produced substantial weight loss in the cohort, with median total weight loss of 21% and excess weight loss of 52% at six months. What the findings do say is narrower: among patients who had the same procedure, those with higher skeletal muscle mass before and after surgery were more likely to be in the remission group. (medindia.net) Because the study was retrospective and relatively small, it shows an association rather than proving cause and effect. ### What should readers watch next? The next step is whether larger studies test whether preserving or building muscle around bariatric surgery improves remission rates prospectively. (spandidos-publications.com) For now, the underlying study is available in *Biomedical Reports* under the title “Relationship between remission rate of type 2 diabetes and skeletal muscle after laparoscopic sleeve gastrectomy,” and Medindia published a secondary summary on May 20, 2026.