A nutrient drink test to assess maximum tolerated volume and postprandial symptoms: effects of gender, body mass index and age in health.

To assess the effects of age, gender and body mass index on the maximum tolerated volume of a nutrient drink and postprandial symptoms in health. Healthy adolescents (15 M, 15 F, aged 13-17 years) and adults (15 M, 25 F, aged 19-51 years) ingested Ensure (1 kcal mL-1) at a rate of 30 mL min-1. The maximum tolerated volume was recorded. Thirty minutes later, bloating, fullness, nausea and pain were rated using visual analogue scales. The Mann-Whitney test was used for comparisons between groups using body mass index and maximum tolerated volume as covariates. Age-related differences in maximum tolerated volume were noted between adolescents and adults, and were observed in both genders. Adults had higher scores for bloating and pain, and lower scores for fullness. Gender-related differences in maximum tolerated volume were noted in the group as a whole, and separately for adolescents and adults. Females had higher scores for nausea and pain. Gender and age-related differences in the maximum tolerated volume of a nutrient drink and postprandial symptoms should be considered in future studies of upper gastrointestinal symptoms in disease. Body mass index does not appear to influence maximum tolerated volume beyond its association with age and gender.