Older obese people with mild cognitive impairment who lose a small amount of weight may see some improvement on tests of thinking skills, according to a new study.
Mild cognitive impairment causes slight but noticeable declines in memory and thinking skills, and increases the risk of Alzheimer’s or other forms of dementia developing later, according to the Alzheimer’s Association.
“Increased adiposity has been correlated with reduced volume in a number of brain regions,” said lead author Dr. Nidia Celeste Horie of the University of Sao Paulo School of Medicine in Brazil. Calorie restriction has many benefits for humans, including reduced abdominal fat mass, and may also improve the resilience of synapses in the brain, she said, Reuters reported.
“At the moment, obese individuals should try to lose weight as young as they can, to protect health in general and the brain in particular, and obese elderly with mild memory problems should try to lose weight to improve comorbidities, knowing that at least it will not be harmful for cognitive skills and with luck they could be preventing dementia.”
The researchers divided 80 obese people over age 60 with mild cognitive impairment into two groups, one of which received usual medical care while the other also met in group nutritional counseling meetings for a year.
All the participants were advised to meet physical activity guidelines, including doing at least 150 minutes of moderate-intensity aerobic exercise or walking throughout the week, or if limited due to health conditions, aiming to be as physically active as possible.
At the start, all the participants had a body mass index (BMI) of at least 30, which by the one-year point had decreased by an average of 1.7 points.
Performance on a battery of physical tests tended to improve during the study. As BMI decreased, thinking skills, verbal memory, language and executive function appeared to increase based on cognitive tests. The improvements were more pronounced for younger seniors, according to the results in the Journal of Clinical Endocrinology and Metabolism.
“The mild weight loss was initially disappointing, but after a more deep analysis, we could see that even with small weight changes the decrease of adiposity was correlated with cognitive improvement,” Horie told Reuters Health.
“In a way it could be a bit risky because if you are already going into dementia, it might not be a good idea to lose weight,” said Dr. Agnes Floel of Charite-Universitaetsmedizin Berlin in Germany, who was not part of the new study.
But this proof of concept study indicates that calorie restriction is safe for people with mild cognitive impairment, Floel told Reuters Health.
