From aroma cue to feeding behavior: Sichuan pepper essential oil aroma stimulates appetite via cognitive and physiological pathways

Reduced food intake is a key contributor to malnutrition. The sense of smell plays a fundamental role in appetite regulation, and olfactory stimulation with certain spice essential oils can facilitate oral intake. The present study examined three Sichuan pepper (genus Zanthoxylum) essential oil (SPEO) types by assessing their effects on self-reported appetite ( n = 348) and ad libitum food intake ( n = 78) in humans, and on feeding behavior and hypothalamic neuropeptide expression in mice. In humans, exposure to SPEO aromas enhanced general appetite and modulated sensory-specific appetite, and increased total food intake by 15–19% in male participants with a shift toward salty foods. This effect was more pronounced in frequent consumers, supporting a learned, cognitive pathway. Concurrently, in mice, SPEO inhalation significantly promoted acute food intake, which was closely associated with altered mRNA expression profiles of hypothalamic feeding-related neuropeptides (upregulating MCH and orexin, downregulating POMC). Further analysis identified five appetite-enhancing volatile compounds (β-Phellandrene, Linalool, Ocimene, Eucalyptol, Linalyl acetate). Collectively, these findings support the appetite-promoting effect of SPEO aroma and suggest that this effect involves both convergent cognitive and physiological pathways.