Acute stress attenuates the coupling between gastric interoception and snack consumption

A comprehensive understanding of the mechanisms underlying eating behavior is crucial for preventing and treating obesity and eating-related disorders. Gastric interoceptive sensitivity, defined as the perceptual threshold of satiation and fullness, is a key physiological marker of meal termination. Although stress is known to influence eating behavior, its impact on the relationship between gastric interoception and food intake remains insufficiently understood. This study behaviorally examined the association between gastric interoceptive sensitivity and snack consumption under high- and low-stress conditions, while accounting for individual eating traits. In 61 fasted adults, gastric interoceptive sensitivity and self-determined snack intake were assessed following both a stress and a control task across four laboratory sessions. Gastric interoceptive sensitivity was measured using a novel paradigm, the Magic Table (MT). Multilevel analyses showed that both satiation and fullness perception thresholds were significantly associated with snack consumption. Under stress, however, only the fullness threshold remained significantly related to snack intake. Higher emotional and restrained eating scores were linked to a weaker association between gastric interoceptive sensitivity and snack intake, whereas higher uncontrolled eating scores showed the opposite pattern. These findings suggest that satiation and fullness signals guide snack termination under low stress, whereas acute stress and certain eating styles weaken the coupling between gastric signals and behavioral regulation. Dysregulated eating may therefore reflect impaired integration of interoceptive input into decision-making, particularly under stress. Beyond enhancing interoceptive sensitivity, studies on interoceptive-focused interventions may benefit from strengthening the integration of satiation signals into eating decisions, especially in stressful contexts.