Research found after accounting for factors, such as age and education level, people with type 1 diabetes were nearly three times as likely to develop dementia as people without diabetes. People with type 2 diabetes were twice as likely to develop dementia as people without diabetes.

Having type 1 diabetes is associated with a higher risk of developing dementia, according to a study published March 18, 2026, in Neurology®, the medical journal of the American Academy of Neurology. Type 2 diabetes is also associated with a higher risk of dementia compared with not having diabetes. This study shows an association and does not prove that diabetes causes dementia.