DIETARY-FAT MODULATES GASTRIC LIPASE ACTIVITY IN HEALTHY HUMANS

The aim of this study was to determine whether the amount of dietary f at modulates the activity of gastric lipase in humans. Gastric juice w as 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 cond itions and the second hour after pentagastrin stimulation (6 mu g/kg b ody wt). Gastric lipase and pepsin activities were quantitated at 15-m in intervals and total enzyme outputs were calculated. Under baseline conditions there was a tendency for higher output of gastric Lipase an d 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 af ter pentagastrin stimulation (gastric lipase: 1323 compared with 875 U /h, pepsin: 191 751 compared with 128 961 U/h, for high-fat compared w ith 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 ga stric enzymes in humans.