Gastric Emptying, Sensory Acceptability, Satiety, and Exploratory OD-Based Total Ghrelin Responses to Oral Nutritional Supplement Beverages in Healthy Adults: A Pilot Crossover Study.

BACKGROUND & AIMS: Oral nutritional supplements (ONS) are widely used in clinical nutrition support, but gastrointestinal tolerance, satiety, and sensory acceptability may influence intake and adherence. Thus, this pilot crossover study compared gastric emptying, subjective appetite, sensory perception, and exploratory total ghrelin responses following four ONS-related beverages differing in protein content, energy density, osmolarity, and texture. METHODS: Five healthy adults (23-30 years) consumed four 200 mL drinks on separate study days in a single-center fixed-order crossover study. Gastric emptying was estimated using the paracetamol absorption test, with time to maximum concentration (Tmax) and area under the concentration-time curve (AUC) as outcomes. Appetite and sensory perception were assessed using visual analog scales (VAS). Total ghrelin was analyzed by sandwich ELISA and interpreted descriptively using optical density (OD)-based time profiles and 30-150 min AUC/iAUC values because assay limitations did not support robust absolute concentration reporting. RESULTS: Lower-energy, lower-protein drinks (A and B) reached peak paracetamol concentration earlier than higher-energy, higher-protein drinks (C and D). Tmax differed significantly between drinks, whereas total paracetamol AUC and VAS satiety scores did not differ significantly. Sensory responses varied between participants, and the thickest drink (D) was generally perceived as less acceptable in relation to mouthfeel. Exploratory OD-based ghrelin profiles suggested a more sustained reduction after Drink D, with the lowest 30-150 min iAUC (-19.46), while Drinks A, B, and C showed positive iAUC values (4.44, 17.49, and 9.07, respectively). CONCLUSION: Beverage composition influenced gastric emptying and exploratory OD-based ghrelin response profiles, while subjective satiety responses remained variable. Higher-protein formulations may provide nutritional value without clearly increasing subjective satiety, but sensory acceptability remains important for clinical use. Larger randomized studies in patient populations are needed to confirm these findings.