For people with prediabetes, bringing blood sugar levels back to the normal range may significantly lower the long-term risk of serious heart problems, according to new research published in The Lancet Diabetes & Endocrinology.
Blood glucose levels are strongly shaped by eating patterns, particularly how the body processes carbohydrates over time. In prediabetes, that system begins to falter, leading to higher-than-normal blood sugar after meals and between meals. The new study suggests that when those glucose levels return to normal, the benefits may extend far beyond diabetes prevention and into long-term heart health.
The research, led by investigators at King’s College London and University Hospital Tuebingen, reanalyzed decades of follow-up data from two landmark diabetes prevention trials in the United States and China. Researchers found that people who achieved remission from prediabetes had substantially lower rates of cardiovascular death and hospital admissions for heart failure compared with those who did not.
Prediabetes affects more than one-third of adults in the United States and more than 1 billion people worldwide. While it is often framed as a warning sign for type 2 diabetes, it is also linked to increased cardiovascular risk, even before diabetes develops.
In the analysis, participants who returned their blood glucose levels to the normal range had a 58% lower risk of dying from cardiovascular causes or being hospitalized for heart failure. That reduction in risk persisted decades after glucose levels normalized, suggesting a lasting protective effect.
Researchers also observed a 42% lower risk of major cardiovascular events, including heart attack and stroke, among those who achieved prediabetes remission.
“This study challenges one of the biggest assumptions in modern preventative medicine,” said Dr. Andreas Birkenfeld, the study’s lead author and a reader in diabetes at King’s College London and University Hospital Tuebingen.
For years, lifestyle changes such as eating healthier and exercising more have been encouraged for people with prediabetes, but the data suggest cardiovascular risk declines most clearly when those changes lead to sustained improvements in blood sugar regulation.
Importantly, the findings do not suggest that nutrition and physical activity are unimportant. In both trials analyzed, dietary changes and increased physical activity were central to the original interventions. However, earlier analyses of the same studies showed that lifestyle changes alone did not reduce cardiovascular disease risk unless they resulted in lasting normalization of blood glucose levels.
That distinction highlights an important nuance for nutrition science. Simply improving food choices in general terms may not be enough if blood sugar levels remain elevated. What appears to matter most for long-term heart health is whether eating patterns lead to meaningful, durable improvements in glucose control.
The analysis drew on data from the U.S. Diabetes Prevention Program Outcomes Study and the Da Qing Diabetes Prevention Outcomes Study in China. Both studies followed participants with prediabetes for several decades and focused on lifestyle-based interventions, including diet and physical activity.
Results were consistent across both populations, strengthening confidence that the association between prediabetes remission and reduced cardiovascular risk applies across different cultural and dietary contexts.
“The study findings mean that prediabetes remission could establish itself alongside lowering blood pressure, cutting cholesterol and stopping smoking as a major tool for preventing heart attacks and deaths,” Birkenfeld said.
Researchers cautioned that the study shows an association, not proof that lowering blood sugar alone directly prevents cardiovascular disease. Still, the findings suggest that nutritional strategies that meaningfully improve glucose regulation may play a critical role in long-term heart health.
Prediabetes is often treated as a temporary phase rather than a condition with long-term consequences. This study suggests that how people eat during this stage may influence cardiovascular health years later, not just diabetes risk.
For people with prediabetes, the findings reinforce that nutrition matters most when it leads to measurable metabolic change. Monitoring blood sugar trends and working with health care providers to support sustained glucose control may be an important part of protecting heart health over time.
This research was supported by multiple public health agencies and research organizations in the United States, China and Germany, including the National Institute of Diabetes and Digestive and Kidney Diseases, the Centers for Disease Control and Prevention, the American Diabetes Association and several international government and academic institutions.