Background/objectives: The aim of this study was to evaluate the reliability of a food menu to measure energy and macronutrient intake within the laboratory and under real-life conditions in adolescents.
Subjects/methods: A total of 12 boys and 8 girls (age 14.3 (s.d. 2.4) years, body mass index (BMI) 20.8 (s.d. 4.0) kg/m(2)) completed two identical in-laboratory sessions (ILS) and two out-of-laboratory sessions (OLS). During the ILS, participants had ad libitum access to a variety of foods (74 items in total), which they chose from a menu every hour, for 5 h (0800-1300 h). For the OLS (1300 h until bedtime), the foods were chosen from the same menu at 1300 h and packed into containers to bring home with them.
Results: Test-retest analysis of energy and macronutrient intake revealed no significant differences (ILS and OLS). Intra-class correlations ranged between 0.69 and 0.83 (ILS) and between 0.48 and 0.73 (OLS) for energy and macronutrient intake (all P<0.01). Within-subject coefficients of variation ranged between 12.9% and 23.5% for the ILS and between 24.0% and 37.7% for the OLS. Bland-Altman plots showed acceptable agreement. Finally, the food menu was well appreciated by the participants with a 75% appreciation rate on a visual analog scale.
Conclusions: This food menu provides a reasonably reliable measure of energy and macronutrient intake in adolescents, irrespective of sex and BMI, especially inside the laboratory setting. Despite the difficulties in capturing a stable measure of energy intake in research, this tool could be a useful addition to the methods currently used to assess ad libitum food intake in youth.