Imprecise control of energy intake: Absence of a reduction in food intake following overfeeding in young adults

The objective was to examine the extent to which overfeeding reduces spontaneous food intake in humans. Twelve normal-weight adults participated in the three stage study. During the 14 day baseline period and 21 day recovery period, food intake was consumed ad libitum, beyond a minimum 5 MJ (1200 kcal) basal diet. During the 13 day period of overfeeding, each subject consumed 35% more energy than they consumed at baseline. Overfeeding resulted in a weight gain of 2.3 +/- 0.37 kg, (p < 0.0001), approximately half the weight gain was determined to be fat (1.2 +/- 0.19 kg, p < 0.0001) by underwater densitometry. Following overfeeding, mean daily caloric intake was not significantly suppressed returning immediately to baseline values. Despite normal energy intake, participants lost 1.3 < 0.24 kg of body weight (p < 0.0001), of which 0.75 +/- 0.15 kg (p < 0.0001) was fat. These results indicated that (1) the physiological control of eating behavior in humans is not the major mechanism responsible for the recovery of body weight following a period of overfeeding and (2) an increase in energy expenditure of 1.28 MJ (307 kcal)/day or about 14% was required to account for the weight loss following overfeeding. 2005 Elsevier Inc. All rights reserved.