It’s well-known that type 2 diabetes can cause medical complications in certain organs, including the brain. But overweight and obese people with early-stage type 2 diabetes have more severe abnormalities in brain structure and cognition than normal-weight people with type 2 diabetes, according to a new study in Diabetologia, the journal of the European Association for the Study of Diabetes.
Having type 2 diabetes and being overweight, then, can combine to have a greater effect on brain structures.
“There’s a general agreement that type 2 diabetes is a risk factor for various types of both structural and functional abnormalities in the brain,” said Dr. Donald C. Simonson, a co-author of the study and an endocrinologist specializing in diabetes. “Simple obesity also shows the same type of abnormalities in a milder stage. You can see where it’s not quite exactly normal but not quite as bad as someone with diabetes.
“So, if you have both, will it be worse than if you have them alone? That’s what we looked at in this particular study,” said Simonson, who teaches at Harvard’s T.H. Chan School of Public Health.
In particular, the temporal lobe appears vulnerable to the combined effects of type 2 diabetes and being overweight or obese, the researchers say. The temporal lobe is implicated in language comprehension and long-term memory.