Effects of Ramadan Fasting on Cognitive Performance and Mood in Young Adults

Ramadan fasting is a culturally embedded lifestyle practice characterized by marked changes in sleep–wake patterns, hydration, caloric intake, and daily routines. These shifts may influence cognitive performance efficiency and emotional regulation, particularly in adolescents and young adults undergoing continued neurodevelopment. This study examined cognitive performance and mood among 56 healthy Muslim young adults (ages 18–20) using a within-subject design that compared fasting and non-fasting days under controlled conditions. Participants completed computerized attention and working-memory tasks, a psychotechnical test of processing speed, and the Profile of Mood States (POMS) questionnaire. Fasting was associated with a substantial decline in concentration (–44.6%) and a significant reduction in psychotechnical performance, where memory showed a small, non-significant decrease. Mood outcomes revealed higher levels of tension, anger, and fatigue during fasting, alongside a significant reduction in vigor; depressive symptoms remained stable. These findings suggest that fasting disproportionately affects attentional control and executive efficiency, which appear more sensitive than memory to metabolic, circadian, and behavioral changes. The relative stability of depressive symptoms may reflect belief-based and contextual emotional regulation mechanisms that support affective balance despite increased physiological and attentional load. By integrating cognitive and emotional outcomes, this study contributes to understanding how lifestyle-embedded fasting practices modulate cognitive performance under ecologically valid conditions, with implications for cognitive enhancement research, education, and applied health contexts.