A nutritional supplement contains free essential amino acids and intact protein. From a kinetics perspective, which component will most rapidly increase plasma essential amino acid concentrations after ingestion and why?

• A. Intact protein will increase plasma essential amino acids faster because chewing and gastric mixing immediately liberate amino acids that are absorbed faster than free forms.
• B. Both forms will appear at identical rates because enterocytes cannot distinguish free amino acids from those derived from protein digestion and absorption kinetics are matched exactly.
• C. Free essential amino acids will increase plasma concentrations most rapidly because they require no digestion and can be absorbed directly by specific transporters, whereas intact protein requires sequential enzymatic breakdown before absorption.
• D. Neither will affect plasma amino acid concentrations significantly because amino acids are stored in a tissue reservoir that buffers any changes regardless of ingestion form.

Answer: (C)