The link between diabetes and dementia
July 6, 2023—Diabetes can affect a person's health from head to toe—including brain health. People with diabetes are more likely to develop brain problems, including Alzheimer's disease and other forms of dementia. The good news: If you have diabetes, you can take steps to help keep your brain healthy.
Blood sugar and brain function
Our brains depend on glucose. In fact, the American Heart Association says the brain uses 20% to 30% of the blood glucose circulating through the body. And because brain tissue can't store glucose, it's sensitive to highs and lows.
If blood sugar is too low, the brain doesn't have enough energy to perform its job properly. Low blood sugar can lead to serious problems very quickly, including seizures or coma. According to the Centers for Disease Control and Prevention (CDC), it may also affect the brain in the long run. Some research has suggested that repeat problems with low blood sugar are connected to memory and attention problems.
If blood sugar is too high, it causes damage to the brain's blood vessels. Damaged blood vessels may not deliver enough oxygen—killing brain cells and leading to dementia.
Some research suggests that high blood sugar levels can increase beta-amyloid protein. This is a brain protein found in patients with Alzheimer's disease, the most common form of dementia. And in Alzheimer's patients, the rate of diabetes and glucose intolerance—a precursor to diabetes—is very high.
High blood sugar is also linked to stroke, another cause of dementia. And people with diabetes are twice as likely to have a stroke as those without diabetes, the American Stroke Association reports. Why? When blood sugar levels are high, fatty deposits or clots can develop in blood vessels. Over time, those clots can grow to restrict blood and oxygen flow to the brain, causing a stroke.
There's more research to be done about the connection between diabetes and brain health. But if you have diabetes, the increased risk of stroke and dementia is yet another reason to control your blood sugar levels.
Staying healthy with diabetes
If you have diabetes, these tips from CDC may help you protect your brain. Ask your doctor for help to get started. They can give you advice on how to choose healthy goals, manage your diabetes, and reduce your risk for stroke and dementia.
- Stay at a healthy weight.
- Keep track of your blood sugar, and keep it at a healthy level.
- Make physical activity part of your regular routine.
- Eat a healthy diet.
- Take your medications as prescribed—and let your doctor know if there's any problem.
- Avoid alcohol and smoking.
- Stay on top of stress. These seven self-care activities can help.
- Alzheimer's Association. "Diabetes and Cognitive Decline." https://www.alz.org/media/documents/alzheimers-dementia-diabetes-cognitive-decline-ts.pdf.
- American Heart Association. "Diabetes and Dementia Risk: Another Good Reason to Keep Blood Sugar in Check." https://www.heart.org/en/news/2021/07/21/diabetes-and-dementia-risk-another-good-reason-to-keep-blood-sugar-in-check.
- American Stroke Association. "Let's Talk About the Connection Between Diabetes and Stroke." https://www.stroke.org/-/media/Stroke-Files/Lets-Talk-About-Stroke/Prevention/Lets-Talk-About-the-Connection-Between-Diabetes-and-Stroke.pdf.
- Bright Focus Foundation. "Diabetes: A Modifiable Risk Factor for Alzheimer's Disease." https://www.brightfocus.org/alzheimers/article/diabetes-modifiable-risk-factor-alzheimers-disease.
- Centers for Disease Control and Prevention. "The Effects of Diabetes on the Brain." https://www.cdc.gov/diabetes/library/features/diabetes-and-your-brain.html.