Millions of people worldwide live with prediabetes. It is estimated that one in ten adults is affected, although the number of unreported cases means the real figure is significantly higher. Prediabetes is a condition in which blood sugar values are elevated but do not yet meet the criteria for diabetes. It often remains undetected for a long time, as affected individuals initially have no symptoms. The body’s cells become more resistant to endogenous insulin hormone. As a result, less sugar moves from the blood into the body cells and the blood sugar level increases. The risks are considerable: If left untreated, there is a high risk of developing type 2 diabetes later on—a disease that affects more than 460 million people worldwide. It can lead to serious complications, such as cardiovascular disease or cancer.
Normal blood sugar level as a milestone
Strategies recommended to date—including in current guidelines—for the prevention of type 2 diabetes in people with prediabetes primarily focus on reducing weight through a healthy diet and increased physical activity. This strategy, which is limited to weight alone, could be broadened on the basis of the new analysis results.
A long-term study conducted by the Department of Diabetology, Endocrinology and Nephrology at the University Hospital Tübingen showed that 234 of the more than 1100 study participants lost no weight or even gained weight over the course of a year despite undergoing lifestyle changes. Nevertheless, a good 22 percent of them normalized their blood sugar levels. The development of type 2 diabetes was monitored over a period of up to a further 9 years. Without weight loss, this group was up to 71 percent less likely to develop diabetes. This figure is almost identical to that of individuals who were able to reduce their risk of type 2 diabetes by losing weight (73 percent).
Fat distribution as a decisive factor
The analysis paid particular attention to fat distribution. The relationship between visceral fat (the inner abdominal fat surrounding the organs) and subcutaneous fat (the fatty tissue located directly under the skin) was examined. Visceral fat releases signaling molecules that promote inflammation and disrupt hormone balance, which leads to insulin resistance and is thus directly linked to type 2 diabetes. Study participants whose blood sugar levels returned to normal without losing weight had a lower percentage of abdominal fat as a result of lifestyle changes compared to those whose blood sugar levels remained in the prediabetes range.
Body weight no longer the sole indicator
“Restoring a normal fasting blood sugar level is the most important goal in preventing type 2 diabetes and not necessarily the number on the scale,” says Prof. Dr. Andreas Birkenfeld, study leader and director of the Institute for Diabetes Research and Metabolic Diseases (IDM) of Helmholtz Munich at the University of Tübingen. “Exercise and a balanced diet have a positive effect on blood sugar levels, regardless of whether weight is reduced. Losing weight remains helpful, but our data suggests that it is not essential for protection against diabetes,” he continues. “In future, guidelines for the prevention and treatment of type 2 diabetes should not only take weight into account, but above all blood glucose control and fat distribution patterns,” adds Prof. Dr. Reiner Jumpertz-von Schwartzenberg, who, as last author, was involved in the study alongside Prof. Dr. Birkenfeld.
A healthy lifestyle as a recipe for success
However, the study results highlight the importance of including target glycemic values, i.e., guideline blood sugar values, in practice guidelines in addition to weight reduction targets. Prediabetes remission is the most effective way to prevent future type 2 diabetes, and the analysis suggests that this is partly independent of weight loss. Nevertheless, sufficient physical activity and a balanced diet remain the key means to bring blood sugar values within a normal range.
Original publication:
Sandforth, A. et al. Prevention of type 2 diabetes through prediabetesremission without weight loss. Nature Medicine (2025). DOI: 10.1038/s41591-025-03944-9
Scientific contact:
Prof. Dr. Andreas Birkenfeld
Medical Director
Department of Diabetology, Endocrinology, and Nephrology
University Hospital Tübingen
Institute for Diabetes Research and Metabolic Diseases (IDM) of Helmholtz Munich at the University of Tübingen
Prof. Dr. Reiner Jumpertz-von Schwartzenberg
Head of Clinical Studies Center
Department of Diabetology, Endocrinology, and Nephrology
University Hospital Tübingen
Institute for Diabetes Research and Metabolic Diseases (IDM) of Helmholtz Munich at the University of Tübingen
Press contact:
Universitätsklinikum Tübingen
Stabsstelle Kommunikation und Medien
Hoppe-Seyler-Straße 6, 72076 Tübingen
Phone: +49 (0)7071 29-88548
presse@med.uni-tuebingen.de
Founded in 1805, Tübingen University Hospital is one of the leading centers of university medicine in Germany. Being one of the 33 university hospitals in Germany, it contributes to the successful combination of high-performance medicine, research and teaching. More than 400,000 inpatients and outpatients from all over the world benefit from this combination of science and practice every year. The clinics, institutes and centers bring together specialists from a wide range of disciplines under one roof.
The experts work together on an interdisciplinary basis and offer each patient the best possible treatment based on the latest research findings. The University Hospital of Tübingen is researching for better diagnoses, therapies and chances of recovery. Many new treatment methods are being clinically tested and applied here. In addition to diabetology, research in Tübingen focuses on neurosciences, oncology, immunology, infection research and vascular medicine. Over the past 25 years, the Chair of Diabetology / Endocrinology has been a center of interdisciplinary research, particularly involving surgery, radiology and laboratory medicine.
The discovery of prediabetes subtypes was only possible thanks to interdisciplinary collaboration. The University Hospital is a reliable partner of four of the six German Centers for Health Research initiated by the federal government. www.medizin.uni-tuebingen.de/en-de
Helmholtz Munich is a top biomedical research center. Its mission is to develop solutions for a healthier society in a rapidly changing world. Interdisciplinary research teams focus on various diseases, in particular the treatment and prevention of diabetes, obesity, allergies and chronic lung diseases. www.helmholtz-munich.de/en
The German Center for Diabetes Research (DZD) is a national association that brings together experts in the field of diabetes research and combines basic research, translational research, epidemiology and clinical applications. The aim is to develop novel strategies for personalized prevention and treatment of diabetes. Members are Helmholtz Munich – German Research Center for Environmental Health, the German Diabetes Center in Düsseldorf, the German Institute of Human Nutrition in Potsdam-Rehbrücke, the Paul Langerhans Institute Dresden of Helmholtz Munich at the University Medical Center Carl Gustav Carus of the TU Dresden and the Institute for Diabetes Research and Metabolic Diseases of Helmholtz Munich at the Eberhard-Karls-University of Tuebingen together with associated partners at the Universities in Heidelberg, Cologne, Leipzig, Lübeck and Munich. www.dzd-ev.de/en
