EFFECTS OF MEAL VOLUME AND COMPOSITION ON GASTRIC MYOELECTRICAL ACTIVITY

The absence of a standard meal in electrogastrography may limit its cl inical significance. Different meals may fail to produce the expected postprandial motility pattern. The aim of this study was to investigat e the effect of meal volume and composition on postprandial myoelectri cal activity. Fourteen healthy subjects were given four meals that dif fered from a ''reference meal'' in one single parameter (volume, calor ie, or fiber content). Gastric myoelectrical activity was measured usi ng surface electrogastrography. Spectral and statistical analyses were performed to investigate the effect of food properties on electrogast rogram (EGG) parameters. it was found that the reference meal produced a postprandial increase in the dominant frequency (P < 0.007), domina nt power (P < 0.04), and percentage of normal 2-4 cycle/min gastric sl ow waves (P > 0.05). Similar changes were observed with the low-volume and high-fiber meals but not with the reduced-calorie meal. Easting E GG parameters in all four sessions showed no significant difference. I t was concluded that low-calorie meals do not result in expected postp randial physiological responses and thus are not appropriate for EGG t ests. A volume reduction of down to one-half the volume of a regular m eal does not affect postprandial changes of the EGG; thus a condensed test meal may be recommended for symptomatic patients.