Cortical thickness, neurocognitive, and body composition effects of fasting during Ramadan

Background: We aimed to study the anatomical, physiological, and cognitive function of healthy individuals practicing fasting during the month of Ramadan. Measurements were taken 1 week before and 2 weeks after Ramadan fasting. Materials and Methods: Twelve healthy male individuals (mean age +/- standard error of the mean: 34.3 +/- 2.9 years; body mass index: 26.26 +/- 1.4 kg/m(2)) were assessed for various parameters before and after Ramadan fasting. All the tests were performed in the morning. Body composition characteristics were assessed by bioelectrical impedance analysis using a commercially available body composition analyzer. For neurocognitive analysis, participants underwent the stop signal task (SST), pattern recognition memory task (PRM), and spatial working memory strategy (SWM) from the Cambridge Neuropsychological Test Automated Battery. T1-weighted, 1 mm-thick magnetic resonance images were also acquired. Results: Anthropometric analysis showed a significant decrease in body weight, fat-free mass (FFM), trunk FFM, and trunk predicted muscle mass, while the other body composition parameters did not exhibit any changes. The stop signal reaction time (SSRT) latency (ms) (P > 0.05) and PRM did not show any significant difference before and after fasting. SWM task (P < 0.05) improved significantly after fasting. Cortical thickness data of the whole brain were not significantly different after fasting at any brain location. There was a significant correlation between the left amygdala and the SWM strategy (r(2) = 0.518) and between fat and brain segmentation volume (r(2) = 0.375). Conclusion: Our pilot data suggest that Ramadan fasting leads to weight loss and FFM reductions and improve cognitive function.