A pair of research studies have recently pointed out the risk for cognitive impairment with elevated blood glucose readings, including levels that are currently considered high-range normal. In the first study, published in Archives of Neurology, researchers assessed over 700 people with Type 2 diabetes over a period of 10 years, looking at cognitive health measures.
The results showed that the study participants with Type 2 diabetes scored significantly lower on cognitive performance tests compared to participants without this condition. The study concluded that “poor glycemic control may contribute” to reduced cognitive health in diabetic subjects.
The second study, published in the journal Neurology, suggests a more worrisome problem, even for people who haven’t received a diabetes diagnosis. The Neurology study looked at correlations between blood sugar levels and brain region atrophy in 250 participants over a four year period.
The Neurology study found a consistent link between deterioration in the size of the hippocampus, a brain region important for memory and learning, and fasting blood sugar levels no higher than 6.1 mmol/l, or 110 mg/dL. These levels are currently considered high-range normal.
Elevated and sustained blood glucose levels contribute to “metabolic dysfunction”, which includes increased oxidative stress and a heightened inflammatory response in the brain, which are both bad for cognitive health.
Food and drink choices create an active neurofeedback loop with our brain. These recent studies suggest a closer look at what are currently considered “normal” blood sugar levels.