High blood sugar and brain shrinkage

Can having high blood sugar shrink your brain?

Maybe, say Australian researchers in a new study published in the journal Neurology.

Older men and women with blood sugar levels at the high end of normal were shown to have shrinkage in areas of the brain associated with memory – even if their blood sugar levels weren't high enough to put them at risk for diabetes.

Glucose and brain health

In the study, the blood sugar levels of 249 men and women in their 60s were tested. All of the participants were considered healthy, non-obese and did not suffer from memory problems or Alzheimer's disease. Their blood sugar levels were shown to be in the normal range – below 6.1 millimoles per liter.

The participants were given brain scans at the start of the study and then again four years later. Even after accounting for lifestyle factors like drinking alcohol or smoking, the participants with the highest blood sugar levels showed brain shrinkage in the hippocampus and amygdala – areas of the brain associated with memory processing.

“It has been generally assumed that blood glucose in the normal range is not a risk factor for brain health in non-diabetics,” said Nicolas Cherbuin, a study author from Australian National University in Canberra. “If the present results are replicated in other studies, the definition of normal fasting blood glucose levels and of diabetes may need to be re-evaluated.”

Prevention

Brain shrinkage like the type found in the study is also associated with dementia, and doctors have linked poor blood sugar control to Alzheimer's – aka "type 3 diabetes."

Consistently high levels of blood sugar are typically caused by a diet high in sugar, stress, lack of exercise or other lifestyle factors. More research about the different factors involved in controlling blood sugar will be helpful in understanding how brain health is affected, Cherbuin said.

Source: MIssourian