Diabetes and Alzheimer’s linked

Diabetes may increase your risk of Alzheimer’s. But blood sugar control, exercise and a healthy diet may help.

By Mayo Clinic Staff

There’s a lot of research suggesting a connection between diabetes and Alzheimer’s — though those connections aren’t yet fully understood. Not all studies confirm the connection, but many do suggest that people with diabetes, especially type 2 diabetes, are at higher risk of eventually developing Alzheimer’s dementia or other dementias.

Research is still unclear on whether taking steps to prevent or control diabetes may help reduce your risk of cognitive decline.

Understanding the connection

Diabetes can cause several complications, such as damage to your blood vessels. Diabetes is considered a risk factor for vascular dementia. This type of dementia occurs due to brain damage that is often caused by reduced or blocked blood flow to your brain.

Many people with diabetes have brain changes that are hallmarks of both Alzheimer’s disease and vascular dementia. Some researchers think that each condition fuels the damage caused by the other.

Ongoing research is aimed at trying to better understand the link between Alzheimer’s and diabetes. That link may occur as a result of the complex ways that type 2 diabetes affects the ability of the brain and other body tissues to use sugar (glucose) and respond to insulin.

Diabetes may also increase the risk of developing mild cognitive impairment (MCI), a condition in which people experience more thinking (cognitive) and memory problems than are usually present in normal aging. Some research indicates that diabetes may increase the risk of MCI worsening to dementia. Mild cognitive impairment may precede or accompany Alzheimer’s disease and other types of dementia.

As researchers examine the connections between diabetes and Alzheimer’s, they’re also studying potential ways to prevent or treat both diseases. But a recent trial of intranasal insulin showed no cognitive benefit.

Reducing your risk

Working with your health care team to prevent diabetes or manage your diabetes has been shown to be an effective strategy to avoid or reduce complications. Diabetes prevention or effective diabetes management may also help prevent Alzheimer’s disease and other dementias.

Preventing diabetes or managing it successfully may help you avoid other complications, such as:

  • Heart disease
  • Stroke
  • Eye damage
  • Kidney disease
  • Nerve damage, which may cause pain in your feet or hands (diabetic neuropathy)
  • Digestive problems (gastroparesis)
  • Bone and joint problems

Steps to prevent or manage diabetes and avoid potential complications include:

  • Follow your health care team’s recommendations about the most appropriate plan for monitoring your blood glucose, cholesterol level and blood pressure.
  • Eat healthy foods, including fruits, vegetables, whole grains, lean meats, and low-fat milk and cheese.
  • If you’re overweight, eat a healthy diet and exercise to lose weight. Obesity can lead to diabetes and other health problems.
  • Don’t smoke.
  • Aim to exercise for at least 30 minutes every day.
  • Examine your feet daily for sores.
  • Take any prescribed medications on schedule.

Evidence suggests that diet and activity changes that lead to weight loss are especially effective in reducing diabetes risk.

Even small steps can make a big difference. In a major clinical research study, participants with blood sugar levels slightly above normal (prediabetes) cut their risk of developing type 2 diabetes by more than 50 percent through exercise (30 minutes five days a week) and as little as a 5 to 7 percent loss in body weight. That weight loss translates to 10 to 14 pounds (4.5 to 6.4 kilograms) for a 200-pound (about 91-kilogram) person.

May 20, 2021

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