Background: The role of gastrointestinal function in obesity is unknown. Recent studies have shown that satiety in obese patients is influenced by an abnormal gastric capacity.
Aim: An easy and non-invasive tool, the water load test (WLT) was used to evaluate gastric capacity and how it relates to body mass index (BMI) in obese patients.
Methods: The WLT was performed in 32 patients with high BMI and 12 healthy volunteers. Water was ingested at a 15 mL/min rate. The maximal tolerable volume (MTV) was defined as the total ingested volume when patients stopped the test.
Results: A BMI > 30 was significantly associated with higher water consumption (2339 ± 306 mL) compared to controls (1830 ± 240 mL, p = 0.001). The MTV had a positive correlation with BMI (r = 0.68, p = 0.001).
Conclusions: Obese subjects have an increased gastric capacity, as measured with the WLT. This greater drinking capacity has a positive correlation with the subjects' BMI.