DIETARY-FAT MODULATES GASTRIC LIPASE ACTIVITY IN HEALTHY HUMANS

The aim of this study was to determine whether the amount of dietary fat modulates the activity of gastric lipase in humans. Gastric juice was collected from six healthy subjects after 2-wk periods of either a high-fat (50% of energy as fat) or low-fat (25% of energy as fat) diet. The collection period lasted 2 h, the first hour under baseline conditions and the second hour after pentagastrin stimulation (6 mu g/kg body wt). Gastric lipase and pepsin activities were quantitated at 15-min intervals and total enzyme outputs were calculated. Under baseline conditions there was a tendency for higher output of gastric Lipase and pepsin after the high-fat diet than after the low-fat diet (gastric lipase: 745 compared with 446 Um, pepsin: 107 677 compared with 78 505 U/h). The difference in output between diet groups was significant after pentagastrin stimulation (gastric lipase: 1323 compared with 875 U/h, pepsin: 191 751 compared with 128 961 U/h, for high-fat compared with low-fat diet, respectively, P < 0.05). This study is the first to report that a high-fat diet leads to an increase in the activity of gastric enzymes in humans.