Normal blood sugar early slashes heart disease risk for decades

Normalising blood sugar levels could cut the risk of heart disease death or hospitalisation by half, even decades later. New research from long-term follow-up studies in the U.S. and China highlights lasting benefits for people with prediabetes who achieve healthy glucose regulation early on.

In the U.S. Diabetes Prevention Program Outcomes Study (DPPOS), 11.5% of participants returned to normal blood sugar levels after a year of intensive lifestyle changes. These individuals saw a 50% lower risk of cardiovascular death or heart failure hospitalisation over a median of 20 years. The findings held true even if they later developed diabetes or required medication.

A similar study in China reported comparable results. There, 13% of participants who normalised their glucose levels experienced a 51% reduction in heart disease death or hospitalisation three decades later. Both studies defined normal glucose regulation as fasting levels below 5.6 mmol/l, two-hour levels under 7.8 mmol/l, and HbA1c under 5.7%.

Experts note that normalising glucose can reduce abdominal fat, lower inflammation, and improve insulin sensitivity. However, they caution that blood sugar control is only one factor in heart health. Maintaining a healthy weight, diet, and exercise remain critical for reducing overall cardiovascular risk.

While lifestyle changes are still the first-line treatment, newer GLP-1 drugs—unavailable during the original trials—could offer additional support. These medications help regulate blood sugar and promote weight loss, potentially enhancing long-term outcomes.

The research confirms that achieving normal blood sugar levels early can provide lasting protection against heart disease, regardless of later diabetes development. This legacy effect persists for decades, reinforcing the importance of early intervention in prediabetes management.