People with impaired glucose tolerance may show signs of cognitive dysfunction, say researchers.
Impaired glucose tolerance is a pre-diabetic state of hyperglycemia that is associated with insulin resistance and a higher risk of cardiovascular disease.
It can precede Type 2 diabetes by several years, and some lifestyle changes, such as getting to a normal weight and increasing exercise, can help pre-diabetic people avoid that progression completely.
Louise Dye, Ph.D., professor of nutrition and behavior in the Human Appetite Research Unit at the Institute of Psychological Sciences, University of Leeds, presented research in which she examined 31 previous studies regarding cognitive performance under various dietary conditions.
She found that the impaired glucose tolerance group showed difficulties in 12 of 27 cognitive test outcomes, including word recognition, visual verbal learning test, visual spatial learning test, psychomotor test and Corsi block-tapping.
The impaired glucose tolerance group was made up of all middle-aged women who appeared to be in general good health.
"There was significant impairment in those women who were impaired glucose tolerant," Dye said.
"To me, that feels like a ticking time bomb. We need to use food - the diet and food industry - to help us shift these people back from impaired glucose tolerance. By the time they get to Type 2 diabetes, the impairments are much more evident," he said.
She called on the food industry to continue researching the best products for consumers with glucose tolerance issues, such as those foods with increased fiber and those with limited glycemic impact.