Prediabetic individuals who manage to bring their blood sugar levels back to normal can cut their risk of serious heart complications by nearly 60%, according to a major long-term international study that challenges prevailing approaches to diabetes prevention.
The research, published in The Lancet Diabetes & Endocrinology, found that people who achieved remission from prediabetes had a 58% lower risk of cardiovascular death or hospitalisation for heart failure compared to those whose blood glucose levels remained elevated. Notably, the protective effect persisted decades after glucose levels were normalised, suggesting what researchers describe as a “legacy effect” of early metabolic correction.
Prediabetes is a condition in which blood glucose levels are above normal but below the threshold for type 2 diabetes. It affects hundreds of millions globally and is widely regarded as a warning stage before the onset of diabetes. While lifestyle changes such as weight loss, physical activity and dietary improvement are routinely advised, their long-term impact on cardiovascular outcomes has remained uncertain.
The new findings question a central assumption in preventive medicine. “For years, people with prediabetes have been told that losing weight, exercising more and eating healthier will protect them from heart attacks and early death,” said lead author Dr Andreas Birkenfeld, Reader in Diabetes at King’s College London and University Hospital Tübingen. “Although these lifestyle changes are clearly beneficial, the evidence does not support that they reduce heart attacks or mortality in people with prediabetes unless remission is achieved.”
The researchers analysed post-hoc data from two landmark diabetes prevention trials, the US-based Diabetes Prevention Program Outcomes Study (DPPOS), which followed participants for more than 20 years, and the DaQing Diabetes Prevention Outcomes Study in China, which tracked individuals for over 30 years. Together, the studies included participants from diverse cultural and genetic backgrounds, strengthening the global relevance of the findings.
Remission was defined using American Diabetes Association criteria — restoration of normal blood glucose levels — assessed after one year of intervention in the US trial and six years in the Chinese study. The primary outcome measured was a composite of cardiovascular death or hospitalisation due to heart failure. Researchers also examined all-cause mortality and other cardiovascular endpoints.
Across both cohorts, individuals who reached remission experienced significantly lower rates of cardiovascular events and death, even long after active lifestyle interventions had ended. The association remained robust after adjusting for baseline differences such as age, weight and initial glucose levels, notes the study.
Scientists believe the benefits may be linked to improvements in insulin sensitivity and reductions in harmful visceral fat — changes that go beyond weight loss alone. Insulin resistance, a hallmark of prediabetes, is known to damage blood vessels and increase the risk of heart disease even before diabetes develops.
Previous studies have shown that lifestyle interventions can delay the onset of type 2 diabetes and improve cardiovascular risk factors such as blood pressure and cholesterol. However, they have not consistently demonstrated reductions in heart attacks or cardiovascular mortality. The new research suggests that without restoring normal glucose regulation, cardiovascular protection may remain incomplete.
“The findings mean that prediabetes remission could establish itself as a major primary prevention strategy, alongside controlling blood pressure, lowering cholesterol and quitting smoking,” Dr. Birkenfeld said.
Despite the promising results, researchers cautioned that remission remains difficult to achieve. In the two studies analysed, only about 11% to 13% of participants reached remission. This highlights the need for more effective and scalable strategies, particularly for individuals with higher baseline glucose levels.
The authors stressed that future research must explore how lifestyle-based remission programmes can be strengthened or combined with pharmacological approaches to improve outcomes. They also argued that clinical guidelines should consider setting explicit glucose targets for people with prediabetes, rather than focusing solely on weight loss and behavioural changes.
Taken together, the study suggests that achieving remission from prediabetes is not only about preventing diabetes but may also be a powerful, measurable tool for reducing long-term cardiovascular disease and premature death — a shift that could reshape prevention strategies worldwide.
