Validity of reported energy intake in obese and nonobese adolescents.

Daily metabolizable energy intake (ME) and total daily energy expenditure (TEE) were measured in 28 nonobese and 27 obese adolescents over a 2-wk period. Reported ME was significantly (p less than 0.001) lower than measured TEE in both the nonobese and the obese groups (2193 +/- 618 vs 2755 +/- 600 kcal/d and 1935 +/- 722 vs 3390 +/- 612 kcal/d, respectively). Reported ME as a percentage of TEE was significantly lower in the obese than the nonobese group (58.7 +/- 23.6% vs 80.6 +/- 18.7%, respectively). When reported ME was adjusted to account for changes in body energy stores, reported ME still remained significantly lower than TEE in both groups. ME was highly reproducible over the 2-wk period. Intraclass correlation coefficients among days for subjects with complete 14-d diaries were 0.87 and 0.89 for nonobese and obese groups, respectively. In both groups, interindividual variability in ME was significantly greater than intraindividual variability. Our data suggest that reported ME in nonobese and obese adolescents is not representative of TEE or energy requirements.