This randomized, crossover trial compared two breakfast meals that were nearly identical in the amount of calories and protein provided, but the quality of protein in the breakfasts distinguished the two. The egg breakfast supplied high-quality protein, meaning the protein provides all of the essential amino acids. High-quality protein foods, like eggs, contain high concentrations of the amino acid leucine which may play an important role in decreasing body weight.
A previous study by the same researchers demonstrated that an egg breakfast, compared to a bagel breakfast of similar calories, increased feelings of fullness and reduced food intake at lunch resulting in a significant reduction in BMI and waist circumference. "Our previous research did not examine if it was the amount or type of protein that may have contributed to the findings we observed, so this research aimed to distinguish between the two," says Dr. Nikhil Dhurandhar, lead researcher and professor in the laboratory of infection and obesity at Pennington Biomedical Research Center. "The results of this study indicate that protein quality, not just quantity, may affect satiety."
These results also support findings published in the British Journal of Nutrition that demonstrate the timing of dietary protein intake affects feelings of fullness throughout the day. The study concluded that when people ate high-quality protein foods from sources such as eggs and lean Canadian bacon for breakfast, they had a greater sense of sustained fullness throughout the day compared to when more protein was eaten at lunch or dinner.
From the May 14, 2012, Prepared Foods’ Daily News