Proteins are the most potent dietary component stimulating gastrin secretion. When proteins enter the stomach, they trigger G cells in the gastric antrum to release gastrin, which in turn promotes gastric acid (HCl) secretion and enhances gastric motility. This acidification is essential for protein digestion by activating pepsinogen to pepsin. Carbohydrates and fats have a minimal effect on gastrin release compared to proteins. Understanding this mechanism is crucial during gastric surgery to preserve or anticipate changes in gastrin secretion and acid production.

Reference: Ganong’s Review of Medical Physiology, Barrett, 26th Edition.