As the population ages, the need for interventions to maintain brain health and cognitive function becomes increasingly important. A recent exploratory pilot study conducted by Dimitrios Kapogiannis, MD, of the National Institute on Aging and the Johns Hopkins University School of Medicine, suggests that intermittent calorie restriction may have a positive impact on executive function and memory in older adults. This study compared the effects of a 5:2 intermittent fasting plan with a “healthy living” diet on cognitive performance, brain metabolism, and Alzheimer’s-associated biomarkers in individuals aged 55 to 70.
The study included 40 overweight, cognitively normal older adults with insulin resistance, who were randomized to either the intermittent fasting group or the healthy living diet group. The intermittent fasting group followed a 5:2 plan, consisting of 2 days of 480 calories/day (meal replacement shakes) and 5 days of a healthy living diet. On the other hand, the healthy living diet group followed portion control and calorie reduction guidelines from the U.S. Department of Agriculture. Both interventions showed improvements in executive function and memory, with the intermittent fasting group demonstrating better results on certain cognitive measures.
The findings of the study, presented at the Alzheimer’s Association International Conference and published in Cell Metabolism, indicate that both diets led to a decrease in BMI and waist circumference, with intermittent fasting showing superior results. The intermittent fasting group also exhibited markers of increased ketogenesis and high compliance, along with improved insulin signaling biomarkers in neuron-derived extracellular vesicles. Brain glucose levels were reduced with both diets, more significantly with intermittent fasting. Additionally, brainAGE, a measure of the pace of brain aging, decreased with both diets, suggesting potential benefits for brain health.
While the study provides valuable insights into the potential benefits of intermittent calorie restriction on brain health in aging adults, several limitations should be considered. The short duration of the trial may have overlooked long-term effects beyond the 8-week timeframe, and the study’s power may have been limited in detecting smaller effects over time and between the two interventions. It is essential to conduct larger clinical trials to further investigate the effects of various dietary interventions on cognitive function and overall brain health.
The pilot study conducted by Kapogiannis and colleagues suggests that intermittent calorie restriction may hold promise in improving executive function and memory in older adults. By combining intermittent fasting with healthy dietary practices, individuals may potentially enhance brain metabolism, reduce brain aging, and support overall cognitive health. Future research should focus on expanding these findings through larger-scale clinical trials to establish optimal dietary strategies for promoting brain health and longevity in aging populations.