Midlife blood pressure, diabetes and smoking linked to dementia-free lifespan
A study of over 12,000 adults found that avoiding high blood pressure, diabetes and smoking in midlife is associated with about 13 additional years lived without dementia.
A long-term study of more than 12,000 participants followed for an average of 26 years found that middle-aged adults who maintained normal blood pressure, remained free of diabetes and did not smoke lived roughly 13 years longer without dementia than those who smoked and had both hypertension and diabetes. The researchers measured these three risk factors at the start of the study, when participants were aged 45 to 65, and tracked dementia incidence over the subsequent decades.
"Each additional risk factor in midlife was associated with fewer expected years alive and free of dementia," wrote Dr. Jordan Weiss, an assistant professor at the Optimal Aging Institute at NYU Langone and a study author.
The analysis also showed that, irrespective of risk-factor count, women tended to live longer dementia-free than men, and white participants generally had more dementia-free years than Black participants. The authors caution that the study shows an association, not causation, and that risk-factor status was only recorded once, without accounting for changes such as smoking cessation.
The findings align with World Health Organization guidelines released in July 2026, which list smoking, hypertension and diabetes among key modifiable risk factors for dementia. Experts note that additional lifestyle measures—regular physical activity, social engagement, balanced diet, weight control, hearing health and reduced air-pollution exposure—could together prevent up to 45% of dementia cases.
While age, genetics and demographic factors remain strong determinants of dementia risk, the study underscores that midlife health choices can substantially influence the length of a dementia-free life.