LAUSANNE, Switzerland – Meals high in protein promote more fat burning that high-carb meals, and whey burns more fat than casein or soy proteins, according to a new study from Nestlé (Am J Clin Nutr. 2011 Mar;93(3):525-34).
In a randomized, double-blind, crossover design, researchers measured energy metabolism, satiety and glucose control in 23 lean, healthy subjects on separate occasions, before and 5.5 hours after consumption of four test meals that were similar in calories. Three meals consisting of 50-percent protein (whey, casein or soy), 40-percent carbohydrate, and 10-percent fat and a fourth meal consisting of 95.5-percent carbohydrate were compared with a glucose meal that provided the same glucose load as the protein meals.
Results showed the protein-rich meals led to a greater energy expenditure and thermic effect than the high-carbohydrate meal, the effects of whey were significantly greater than those of casein and soy, and were accompanied by a trend for greater fat oxidation. All three proteins (in the presence of glucose) significantly lowered peak glycemia after the meal. Furthermore, casein and soy protein lowered glycemia with little, if any, increase in insulin secretion above that of the glucose component of the meal. Subjective appetite sensations indicated that casein and soy were more satiating than whey, but whey was more “liked” compared with casein and soy.
“Our study confirmed that protein-rich meals promote greater energy expenditure than carbohydrate-rich meals of equal calorie content,” said Kevin Acheson, the Nestlé scientist leading the study. “These findings strengthen the evidence that increased protein content in the diet promotes weight control. Different protein sources could be used for personalized nutrition needs.”
A press release from Nestlé said its researchers will extend the investigation of these results to examine the acute and long-term health benefits of proprietary protein sources.