Thick egg-white shakes used to be the go-to for bodybuilders and strength athletes when they wanted to put on massive muscle. Back then, bodybuilders eschewed egg yolks because of cholesterol concerns. But these days, we know that the cholesterol in egg yolks doesn’t transfer over to your body and make cholesterol levels rise, so eggs are back on the training menu for many.
And it turns out that egg yolks are actually better for building muscle after a workout than the same amount of egg whites, says a new study published in the American Journal of Clinical Nutrition. That's right: You'll get more yoked with yolks.
Researchers gave 18 young guys (so, a small study) an 18g serving of protein from either egg yolks or egg whites after one session of lifting weights. They then took blood samples and muscle biopsies to track muscle protein synthesis. The researchers found that the post-exercise response in building new muscle was 40% greater in those who had the egg yolks compared to just the whites.
"We saw that the ingestion of whole eggs immediately after resistance exercise resulted in greater muscle-protein synthesis than the ingestion of egg whites," said study head Nicholas Burd, Ph.D., a professor of kinesiology and community health at the University of Illinois. "There's a lot of stress on protein nutrition in modern society, and research is showing that we need more protein in the diet than we once thought to maintain health. As world population grows, we need cost-effective and sustainable strategies for improving the use of protein in the diet. This work is showing that consuming egg protein in its natural matrix has a much greater benefit than getting isolated protein from the same source."