The effects of sugar on subsequent eating and mood in obese and non-obese women

The effects of a sucrose drink (160 kcals/40 g cane sugar) on subsequent eating and mood state (Profile of Mood State) were examined in 45 obese and 45 non-obese women in a between-subjects, blind-design, using saccharin and water as two alternative placebos. After sugar, lunch was delayed a mean of 54 minutes relative to normal eating times, and this delay did not vary as a function of body mass. Women with high body dissatisfaction (on the Eating Disorders Inventory) tended to delay eating more after sugar, saccharin or water preloads. The nutritional content of lunch was unaffected by sugar. Nor was mood affected by sugar, although women with a high drive for thinness (EDI) tended to rate themselves as more clearheaded 30 minutes after any preload. It is concluded that when sugar is given blind and everyday eating occurs, eating is delayed. These findings are inconsistent with theories which propose that glucose metabolism directly affects mood. Other effects of sugar on mood and eating behaviour may be due to cognitive factors including beliefs and expectations about eating sweet foods, as well as the reinforcing effects of sweet taste