Effects of dinner composition on postprandial macronutrient oxidation in prepubertal girls.
OBJECTIVE
To see whether a fat-rich (50%) evening meal promoted fat oxidation and a different spontaneous food intake on the following day at breakfast than a meal with a lower fat content (20%) in 10 prepubertal obese girls.


METHODS
The postabsorptive and postprandial (10.5 hours) energy expenditure after a low-fat (LF) (20% fat, 68% carbohydrate, 12% protein) and an isocaloric (2.1 MJ) and isoproteic high-fat (HF; 50% fat, 38% carbohydrate, 12% protein) meal were measured by indirect calorimetry.


RESULTS
Fat oxidation was not significantly different after the two meals [LF, 31 +/- 9 vs. HF, 35 +/- 9 g/10.5 hours, p = not significant (NS)]. The girls oxidized 1.8 +/- 0.9 times more fat than that ingested (11.1 grams) with the LF meal vs. 0.3 +/- 0.3 times more fat than that ingested (27.1 grams) with the HF meal (p < 0.001). Carbohydrate oxidation was significantly higher after an LF than an HF meal (39 +/- 12 vs. 29 +/- 9 g/10.5 hours, p < 0,05). At breakfast, the girls spontaneously ingested a similar amount of energy (1.5 +/- 0.7 vs. 1.5 +/- 0.6 MJ, p = NS) and macronutrient proportions (fat, 23% vs. 26%, p = NS; protein, 9% vs. 10%; carbohydrate, 68% vs. 64%,) independently of their having eaten an HF or an LF dinner.


CONCLUSIONS
An HF dinner did not stimulate fat oxidation, and no compensatory effect in spontaneous food intake was observed during breakfast the following morning. Cumulated total fat oxidation after dinner was higher than total fat ingested at dinner, but a much larger negative fat balance was observed after the LF meal. Spontaneous energy and nutrient intakes at breakfast were similar after LF and HF isocaloric, isoproteic dinners. This study points out the lack of sensitivity of short-term fat balance to subsequently readjust fat intake and emphasizes the importance of an LF meal to avoid transient positive fat imbalance.
Maffeis
Claudio
C
Department of Pediatrics, University of Verona, Polyclinic G.B. Rossi, Piazza L.A. Scuro 6, 34134 Verona, Italy. Claudio.maffeis@univr.it
Schutz
Yves
Y
Chini
Lorenza
L
Grezzani
Alessandra
A
Piccoli
Rita
R
Tatò
Luciano
L
D002648:Child; D003430:Cross-Sectional Studies; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage* / Q000378:metabolism*; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D004734:Energy Metabolism; D005260:Female; D005502:Food; D006801:Humans; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D012146:Rest
D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins