Understanding Ramadan Fasting: Religious, Cultural and Scientific Context

Ramadan fasting represents a unique model of religiously motivated dry intermittent fasting that integrates spiritual devotion, sociocultural structure, and physiological adaptation. Observed annually by Muslims worldwide, it involves abstaining from food, fluids, smoking, and oral medications from dawn until sunset for 29–30 consecutive days. Unlike many modern intermittent fasting approaches, Ramadan fasting prohibits daytime water intake and shifts all meals to nighttime hours, creating a distinct diurnal fasting–feeding cycle. This religious framework shapes behavioral discipline, sleep timing, social interaction, and meal patterns, distinguishing it from voluntary dietary interventions focused primarily on metabolic outcomes. The dawn-to-sunset fasting model induces metabolic adjustments characterized by glycogen utilization, increased lipid oxidation, and gluconeogenesis while generally preserving glucose homeostasis. Despite reductions in physical activity and sleep duration, resting metabolic rate and total energy expenditure remain largely stable. Chronobiologically, Ramadan fasting influences circadian rhythms, altering hormonal patterns including cortisol, melatonin, leptin, and ghrelin. The nocturnal displacement of food intake may create circadian shifts that differ from conventional time-restricted eating protocols, particularly because of the absence of daytime hydration. Ramadan fasting also differs from other intermittent fasting models due to its religious motivation, dry fasting structure, nocturnal feeding window, and sociocultural reinforcement. Caloric intake is not necessarily reduced, and metabolic changes are often modest but adaptive. Additionally, fasting duration varies globally due to seasonal and geographical differences in daylight hours. Extended fasting periods may increase hydration challenges and circadian disruption, yet metabolic stability is generally maintained through physiological adaptation.