EFFECT OF GUAR GUM ON HUNGER AND SATIETY AFTER MEALS OF DIFFERING FAT-CONTENT - RELATIONSHIP WITH GASTRIC-EMPTYING

To determine whether the satiating effects of fiber are due to delayin g gastric emptying or slowing absorption of meals, 3% guar gum was add ed to high- and low-fat soups and gastric emptying rate, hunger, and s atiety were measured in eight male volunteers. Guar gum delayed the em ptying of the low-fat soup but the small delays in the return of hunge r and decline of fullness were significantly correlated with the gastr ic emptying, suggesting mediation by gastric mechanoreceptors. The hig h-fat soup also emptied more slowly but this had no effect on the retu rn of hunger or the decline in fullness. The delays in the return of h unger and decline of fullness were far greater when guar gum was added to the fatty soup; these delays were not correlated with the small ad ditional delay in gastric emptying. This is more compatible with slowe d absorption and prolonged contact of nutrients with intestinal chemor eceptors.