If you develop Type 2 diabetes in middle age, your first priority will be to get your blood sugar under control. After that you may want to take steps to boost your brain health. There’s increasing evidence that a midlife diagnosis of Type 2 diabetes (or prediabetes) is linked to a greater-than-average decline in memory and cognitive skills in later life.

In one study, researchers followed more than 13,000 men and women ages 48 to 67 for 20 years. They found that those diagnosed with Type 2 diabetes or prediabetes in middle age had a 19 percent greater drop in cognitive health as they got older than their healthier counterparts. For example, the mental decline of a 60-year-old person with diabetes was about equal to that of a 65-year-old who was aging normally. What’s more, the subjects with diabetes whose blood sugar was not under control did worse on the tests than those who controlled their blood sugar levels. Similarly, in an earlier study researchers found that the more severe a person’s diabetes, the faster his cognitive decline.

Scientists aren’t sure why Type 2 diabetes might have this effect on thinking and memory. Some speculate that an enzyme involved in controlling insulin, which helps regulate blood sugar, also plays a key role in keeping the brain healthy. Other researchers believe that the damage that diabetes does to the brain's blood vessels is responsible.

Brain saving strategies

Not everyone who develops diabetes or prediabetes in middle age is destined to have problems with thinking and memory as they age. But given how strong the link is it makes sense to do all you can to prevent it.

If you have prediabetes, it’s possible to reverse it, according to the American Diabetes Association:

  • If you’re overweight, try to shed 7 percent of your body weight — about 15 pounds if you weigh 200 pounds, for example.
  • Exercise at least 30 minutes five days a week. Brisk walking is one option.

If you have diabetes, closely follow your doctor’s instructions for controlling your blood sugar. Try to lose weight if you need to and exercise regularly.

Whether you have diabetes or not, regular exercise also can help your brain stay healthy, according to the Alzheimer's Association. So can eating a diet that’s low in fat and cholesterol and rich in fruits and vegetables. It’s also important to stay mentally active by socializing, volunteering, learning a new skill or hobby or doing anything that requires you to use your brain cells.

Kathleen Doheny is a Los Angeles journalist specializing in health, behavior and fitness topics.