Are whole eggs superior for muscle growth compared to egg whites only?
Resistance exercise stimulates muscle protein synthesis (i.e. the process driving muscle adaptation). Protein further increases post-exercise muscle protein synthesis rates. It has recently suggested that protein-rich whole foods may be superior to stimulate muscle protein synthesis compared to just protein.
This study investigated the effect of whole eggs or egg whites (18 grams of protein) on muscle protein synthesis rates following a single resistance exercise session. The yolk was included in the whole eggs treatment, which resulted in 17 grams of additional fat as compared to the egg whites.
Whole eggs stimulated muscle protein synthesis more compared to the egg whites.
There is no clear explanation for the difference. The higher energy intake and insulin response in the whole egg group are unlikely explanations. Fat intake was also higher, but it’s role on muscle protein synthesis is unclear.
The authors speculated that some micronutrients that are only in the egg yolk might increase muscle protein synthesis rates. It’s unclear which micronutrients could be responsible for this and whether other foods also have anabolic micronutrients.
Therefore, whole foods with micronutrients may be the best option for muscle growth.
Go to the next infographic in the protein series:
Supplements or whole-food meals for muscle growth?
Hi Jorn why wasn’t this a factor: “The higher energy intake ….. are unlikely explanations.” Wouldn’t the increased caloric intake potentially allow better adaptations to resistance training or was that factor already ruled out by other means?
Hey Adam,
There’s a bunch of studies that show that acutely, energy intake has little to no impact on muscle protein synthesis rates. For example, studies where MPS rates are similar in a group that gets only protein and a group that get the protein plus a lot of carbs.
However, after a couple of days of lower energy intake, MPS rates begin to drop.