Why is Alzheimer’s dementia (AD) sometimes called “Type 3 diabetes?” What are the symptoms, and how can it be prevented?
Alzheimer’s is a progressive brain disease. People who have this condition gradually lose memory and mental focus. They may have emotional and behavioral changes that put a great load on their families.
The course of Alzheimer’s disease varies dramatically. Some people become severely disabled and die from it. Others may experience only a mild slowing of brain function.
What causes Type 3 diabetes?
How might diabetes cause Alzheimer’s symptoms? Gary Small, MD, a professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA and author of The Alzheimer’s Prevention Program said that high blood sugars cause inflammation throughout the body and brain. Chronic inflammation has been linked with two brain changes typical of Alzheimer’s disease.
In Alzheimer’s, clumps of protein called beta-amyloid plaques form between the brain cells and may block communication. Researchers have discovered that many people with Type 2 diabetes have beta-amyloid deposits in their pancreas like the ones found in the brains of people with Alzheimer’s.
Tau tangles are twisted-up proteins that form within nerve cells of people with Alzheimer’s, interfering with cell function.
We don’t know what causes this nerve damage, but studies done at Brown University and the University of Pennsylvania indicate that insulin resistance, the core of Type 2 diabetes, is a big part of it. Insulin resistance may deprive brain cells of glucose they need to function, causing damage.
On Verywell.com, health writer Esther Heerema, MSW, said, “The brains of those with Alzheimer’s disease who did not have diabetes showed many of the same abnormalities of those with diabetes, including reduced levels of insulin in the brain.”
When a person has insulin resistance in the liver or muscles, he may develop Type 2 diabetes. Insulin resistance in the brain is now being called Type 3. An individual may have either or both types.
People with Type 2 diabetes are 50–65% more likely to develop Alzheimer’s disease than people with normal blood sugars. Studies show that approximately half of people with Type 2 will go on to develop Alzheimer’s in their lifetime. Those with high cholesterol or high blood pressure are at greater risk.
Symptoms of Type 3 diabetes
A person in the early stages of Type 3, or at risk for it, may or may not have elevated blood sugar on a lab test. It is likely he will have one of the warning signs of Alzheimer’s disase, which the Alzheimer’s Association site Alz.org lists as:
• Memory loss that disrupts daily life: Forgetting recently learned information, or important dates or events. People may ask for the same information over and over; or may start writing down things they used to remember easily.
• Challenges in planning and problem solving. People may do things slower. Alz.org gives the examples of following a familiar recipe or balancing a checkbook as tasks that may become difficult.
• People may become confused about dates, places, or names.
• They may have visual problems, which are often first seen in driving.
• They may forget words or lose their train of thought in the middle of a conversation, even in the middle of a sentence.
• They may start losing things, or they may withdraw from work or social activities.
• Their moods or personalities may seem to change.
Notice that any of these changes can come with normal aging, or with other health problems, or with drug or alcohol use. Some people have such problems all their lives. No one symptom proves you have Alzheimer’s disease, Type 3 diabetes, or any kind of dementia. But if you or a loved one do seem to have such symptoms, get a checkup that includes looking at your blood sugar and insulin function.
It all sounds terribly scary, but there are many ways to prevent or improve Type 3 diabetes. Next week I’ll write about what you can do to avoid Type 3, including diet, medications, supplements, and a variety of healthy and doable life changes to strengthen your brain.