About one in ten people in the United States has type 2 diabetes (T2D). Perhaps you’re one of them.

If you are, you may be aware that the metabolic condition can impact other areas of your health, increasing risks for heart attacks, strokes and aneurysms.

But fewer people know that having T2D can set you on the road to cognitive decline by kickstarting mild cognitive impairment (MCI), a transitional phase from cognitive changes in normal aging to those typically found in dementia.

Here’s how and why it happens…

It’s all about the white matter

Your brain is made of grey matter and white matter.

Grey matter is where the processing of sensation, perception, voluntary movement, learning, speech and cognition occurs. It’s where information is gathered.

White matter’s role is to facilitate communication between grey matter and the rest of your body, allowing you to use that information to function in the world.

So, where does diabetes come in?

White matter deteriorates faster with diabetes

In a long-term study led by scientists at Johns Hopkins University, 185 participants were followed for up to 27 years. All had unimpaired cognition at the start.

By the end of the trial, 60 people had progressed to MCI. Eight of those went on to develop dementia.

And T2D was among the factors associated with higher rates of deterioration in white matter over time, as well as MCI…

• Brain scans throughout the study revealed that participants with the most significant declines in white matter had an 86 percent greater risk of developing mild cognitive impairment (MCI).
• There was also a 48% higher risk for MCI if spinal fluid revealed an imbalance between two forms of amyloid beta proteins linked to the formation of Alzheimer’s signature plaques.
• And in participants who had both T2D and an imbalance in amyloid beta proteins, the risk for progressing to MCI increased by 55%!

“These findings highlight that white matter volume changes are closely associated with cognitive function in aging, suggesting that white matter degeneration may play a crucial role in cognitive decline,” write the authors of the study, led by neuroscientists at Johns Hopkins University in the United States.

“As insulin resistance plays a critical role in the formation of amyloid plaques, diabetes may promote Alzheimer’s disease pathology, resulting in an earlier progression from normal cognition to MCI.”

While more research is needed, these results aren’t totally surprising, given the fact that some drugs that treat T2D have been linked to a 35 percent lower risk of dementia in patients.

The importance of controlling insulin

Insulin resistance can lead to a condition known as hyperinsulinemia, which is when your pancreas creates too much insulin.

On its own, hyperinsulinemia is not diabetes. But it is the beginning of the path. If you have insulin resistance, there are steps you can take to change your disease trajectory.

If you have T2D, it’s still possible to save your brain. Manage the condition well, and with your doctor’s guidance and lifestyle changes, studies have shown that, with the right diet, it’s possible to send T2D into remission.

A few more helpful suggestions:

Sources:

Indicators of an aging brain: A 20-year study — Medical Xpress

Type 2 diabetes linked to accelerated brain shrinkage, study reveals — Science Alert

Acceleration of brain atrophy and progression from normal cognition to mild cognitive impairment — JAMA Network

Type 2 diabetes drug linked to 35% lower dementia risk in patients — Science Alert