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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.

PHILLIPS, SARAH M., LINDA G. BANDINI, ELENA N. NAUMOVA, HELENE CYR, SKYE COLCLOUGH, WILLIAM H. DIETZ, AND AVIVA MUST. Energy-dense snack food intake in adolescence: longitudinal relationship to weight and fatness. Obes Res. 2004;12:461-472. Objective: The longitudinal relationship between the consumption of energy-dense snack (EDS) foods and relative weight change during adolescence is uncertain. Using data from the Massachusetts Institute of Technology Growth and Development Study, the current analysis was undertaken to examine the longitudinal relationship of EDS food intake with relative weight status and percentage body fat and to examine how EDS food consumption is related to television viewing. Research Methods and Procedures:One hundred ninetysix nonobese premenarcheal girls 8 to 12 years old were enrolled between 1990 and 1993 and followed until 4 years after menarche. At each annual follow-up visit, data were collected on percentage body fat (%BF), BMI z score, and dietary intake. Categories of EDS foods considered were baked goods, ice cream, chips, sugar-sweetened soda, and candy. Results: At study entry, girls had a mean Ϯ SD BMI z score of -0.27 Ϯ 0.89, consumed 2.3 Ϯ 1.7 servings of EDS foods per day, and consumed 15.7 Ϯ 8.1% of daily calories from EDS foods. Linear mixed effects modeling indicated no relationship between BMI z score or %BF and total EDS food consumption. Soda was the only EDS food that was significantly related to BMI z score over the 10-year study period, but it was not related to %BF. In addition, a significant, positive relationship was observed between EDS food consumption and television viewing. Discussion: In this cohort of initially nonobese girls, overall EDS food consumption does not seem to influence weight status or fatness change over the adolescent period.

OBJECTIVES: To assess the relationship between eating food purchased away from home (FAH) and longitudinal change in body mass index (BMI) z-score among girls, and to assess the longitudinal tracking of eating FAH from childhood through adolescence. DESIGN: Participants kept 7-day dietary records at two points in time. The records included the place and time for all foods consumed. We recorded how often participants ate FAH, calculated the percent of total energy derived from FAH, and classified foods as quick-service food, coffee-shop food, or restaurant food. PARTICIPANTS: Healthy girls (n ¼ 101) between the ages of 8 and 12 y at baseline and 11 and 19 y at follow-up participated in a longitudinal study of growth and development at the Massachusetts Institute of Technology. STATISTICAL ANALYSES: Analysis of variance was used to assess the relationship between change in BMI z-score and both the frequency of eating FAH and energy derived from eating FAH. The participants' baseline BMI z-score was a significant covariate and was controlled for in both models. We used the kappa coefficient to assess FAH tracking from childhood through adolescence. RESULTS: The frequency of eating quick-service food at baseline was positively associated with change in BMI z-score (F ¼ 6.49, Po0.01). Participants who ate quick-service food twice a week or more at baseline had the greatest mean increase in BMI zscore compared to those who ate quick-service food once a week or not at all. Quick-service food eating tracked slightly from childhood through adolescence (k ¼ 0.17, Po0.05). DISCUSSION: Adolescent girls who eat quick-service food twice a week or more are likely to increase their relative BMI over time.

OBJECTIVE: Although research suggests that adolescents, particularly girls, may avoid dairy products due to concerns that these foods are 'fattening,' the longitudinal relation between consumption of dairy foods and relative weight status during adolescence has not been explored. Using data from the MIT Growth and Development Study, a longitudinal study designed to assess the metabolic, dietary, and behavioral factors that predict changes in body composition with growth and development in girls during the adolescent period, the current analysis was undertaken to examine the relation of dairy food intake with relative weight status and percentage body fat (%BF). SUBJECTS: A total of 196 nonobese premenarcheal girls 8-12 y old were enrolled between 1990 and 1993. Girls were followed until 4 y postmenarche. MEASUREMENTS: At each annual follow-up visit, data were collected on %BF by BIA, body mass index (BMI) z-score, and dietary intake (assessed by FFQ). The present analysis is limited to the 178 girls who have at least three annual visits and who have valid anthropometric and food frequency data. In all, 1198 individual measurements were analyzed. RESULTS: At study entry, participants had a mean (s.d.) BMI z-score of À0.27 (0.89), a mean (s.d.) %BF of 23.4 (4.7), and obtained 19.9% (9.2) of daily calories from dairy foods. Linear mixed effects modeling indicated no relationship between BMI z-score or %BF and measures of dairy food or calcium consumption. CONCLUSION: Avoidance of dairy foods due to a possible association with relative body weight is not supported by these findings. We find no evidence that dairy food consumption is associated with BMI z-score or %BF during adolescence, but further research specifically designed to address this question is needed.

1. We tested Krecker's model (1939) which states that the abundance of invertebrates per unit macrophyte biomass varies with plant species and is higher on plants with finely dissected leaves than on plants with broad leaves. The abundance of invertebrates was measured in thirteen lacustrine macrophyte beds in southern Ouebec, Canada. The model was tested for the total abundance of invertebrates and for the abundances of Chironomidae, Cladocera. Cyclopoida, Gastropoda, Hydracarina, Ostracoda and Trichoptera.2. More epiphytic invertebrates were found on the dissected Myriophyllum spp. than on the broad-leaved Potamogeton amplifolius Tuckerm, P. rohbinsii Oakes and Vallisneria americana Michx. (P<0.01). More invertebrates were also found on P. amplifolius than on P. rohbinsii or V. americana (/*<().01). The total abundance of invertebrates was not systematically related to the degree of plant dissection.3. The abundances of Chironomidae, Cladocera, Cyciopoida, Gastropoda, Hydracarina, Ostracoda and Trichoptera varied on different plant species (P<0.01). Contrary to Krecker's hypothesis, however, macrophytes with finely dissected leaves {Ceratophyllum demersum and Myriophyllum spp.) did not in general support more invertebrates per unit plant biomass than plants with large leaves {Potamogeton amplifolius, P. robbinsii and Vallisneria americana).

Energy intake and energy expenditure were assessed in 109 girls aged 8-12 y. Intake was estimated from a 7-d dietary record based on household measures. Expenditure was measured with the doubly labeled water technique during 2-wk period. Overall, the mean (+/-SD) energy intake was 7.0 +/- 1.67 MJ/d and the mean energy expenditure was 8.03 +/- 1.28 MJ/d. The mean difference between intake and expenditure was 1.03 +/- 1.77 MJ/d (P < 0.0001). The mean proportion of actual intake reported was 88.3 +/- 21.0%. Multivariate-regression analysis showed that age and total daily energy expenditure were significantly and independently related to the reporting error. Coefficients for age and total daily energy expenditure were both positive, indicating that as age and daily energy expenditure increased, the magnitude of the error of reporting increased. Income, ethnicity, parental obesity, and body fat were not significantly related to accuracy of reporting. The use of food records to determine energy intake appears to provide more accurate results in younger than in older girls, and the accuracy of the method apparently decreases as energy expenditure increases.

BANDINI, LINDA G. DUNG VU, AVIVA MUST, HELENE CYR, ALISON GOLDBERG, AND WILLIAM H. DIETZ. Comparison of high-calorie, low-nutrient-dense food consumption among obese and non-obese adolescents. Obes Res. 1999;7:438-443. Objective: The purpose of this study was to determine whether obese adolescents eat more high-calorie lownutrient-dense foods than non-obese adolescents. Research Methods and Procedures: Using a crosssectional design, 22 non-obese and 21 obese adolescents kept 14-day food records. Records provided estimates of total daily energy intake and caloric intake from five categories of high-calorie, low-nutrient-dense (HC) foods: candy, chips, soda, baked goods, and ice cream. Body composition was determined by "0 dilution and daily energy expenditure by doubly labeled water. Percentage of energy intake reported (%report) was calculated as the ratio of reported energy intake to measured energy expenditure (x 100%). Results: Both groups underreported energy intake, but the percentage reported was significantly greater in the nonobese group (78.2*20.5% non-obese vs. 55.5+21.8% obese, p