Investigators at the University of Arkansas sought to determine the impact of a protein-based (PRO) breakfast on postprandial energy metabolism, hunger, and lunchtime food intake as compared to the consumption of a carbohydrate-based (CHO) breakfast. Children aged 8–12 years without food allergies or diet-related health conditions were eligible to participate. At baseline, anthropomorphic and blood glucose measurements were performed on all participants. Children were classified into 2 weight groups: normal weight (NW; BMI <85th percentile for age) and overweight (OW; BMI ≥85th percentile).
All participants completed 2 study visits at least 7 days apart in a randomized crossover design in which they were served either a PRO or CHO breakfast. Participants arrived for the study breakfast in a fasting state and first received several measurements: height, weight, resting energy expenditure (EE, determined via indirect calorimetry using the ventilation hood technique and used to calculate carbohydrate and fat oxidation), fasting blood glucose, and baseline appetite (determined by asking participants to rate their perceived hunger, fullness, and desire to eat). The PRO breakfast (1 egg, 2 egg whites, butter, orange juice, and 2 slices of white bread) was 21% protein, 52% carbohydrate and 27% fat; the CHO breakfast (1 waffle, butter, maple syrup, and orange juice) was 4% protein, 67% carbohydrate, and 29% fat. Blood glucose, postprandial EE, and appetite assessments were then measured at several time points following the meal. A buffet-style lunch was served 240 minutes after the study breakfast. Participants were asked to eat until they felt full. All food items in the buffet were recorded and weighed before and after consumption to determine intake. A nutrient analysis of the foods consumed at lunch was calculated. The investigators examined differences between breakfast and weight groups for EE, carbohydrate and fat oxidation, blood glucose, and appetite ratings.
Of 35 children enrolled, 29 completed the study (13 OW). After the PRO breakfast, OW participants had significantly higher postprandial EE and fat oxidation than NW participants did following either breakfast. Fat and carbohydrate oxidation were significantly higher after consumption of PRO than CHO breakfast, independent of weight group. All participants had significantly decreased feelings of hunger and increased feelings of fullness after the PRO compared to the CHO breakfast, but there was no significant effect of breakfast type on food intake at lunch within either weight group.
The investigators conclude that increasing protein and reducing carbohydrate at breakfast leads to increased fat oxidation and satiety, and posit possible long-term beneficial effects on childhood weight.
Dr Springer has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.
The Centers for Disease Control and Prevention report...