Oct. 5 (UPI) -- Controlling blood sugar levels helped people with Type 2 diabetes who were overweight improve cognitive scores, but losing weight, exercise had mixed results, a new study shows.
More than a quarter of U.S. adults 65 or older have Type 2 diabetes, which doubles the risk of cognitive impairment and dementia, including Alzheimer's disease, according to a statement from the Pennington Biomedical Research Center.
"It's important to properly control your blood sugar to avoid the bad brain effects of your diabetes," said study author Owen Carmichael said in a statement.
"Don't think you can simply let yourself get all the way to the obese range, lose some of the weight, and everything in the brain is fine," said Carmichael, a professor and director of Biomedical Imaging at Pennington Biomedical Research Center. "The brain might have already turned a corner that it can't turn back from."
The study, published in the latest issue of The Journal of Clinical Endrocrinology and Metabolism, analyzed whether markers such as body weight, blood sugar control, and physical activity would be associated with improved cognition in 1,089 participants, age 45 to 76, who have Type 2 diabetes.
Researchers theorized that greater improvements in all three markers would lead to better cognitive test scores, but that turned out to be only partially true. While reducing blood sugar levels improved test scores, losing more weight and exercising more didn't always do so.
"Every little improvement in blood sugar control was associated with a little better cognition," Carmichael said. "Lowering your blood sugar from the diabetes range to prediabetes helped as much as dropping from prediabetes levels to the healthy range."
Meanwhile, results from weight loss varied depending on the mental skill, according to Carmichael. More weight loss improved participants short-term memory, planning, impulse control, attention and the ability to switch tasks, but verbal learning and overall memory still declined.
"The results were worse for people who had obesity at the beginning of the study," he added.
Similarly, Carmichael said the study showed that increasing physical activity also benefited people who were overweight more than people with obesity.