Whey protein appears to resist coagulation in the stomach and pass quickly to the intestines (at least when compared to casein and other proteins). Leucine spikes in the blood approximately 40–60 minutes after the ingestion of whey protein,[1] which is quicker than that observed for other protein sources (e.g., tuna, turkey, and egg).[2] As such, whey rapidly stimulates muscle protein synthesis (MPS).
How does whey protein work?
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•Last Updated: May 16, 2025
Whey protein resists coagulation in the stomach and quickly moves to the intestines, which leads to a spike in leucine levels in the blood within 40 to 60 minutes after ingestion. This rapid absorption stimulates muscle protein synthesis more quickly than other protein sources like tuna, turkey, and egg.