Gastrin and ghrelin are stomach hormones with opposing roles in digestion and appetite: Gastrin stimulates stomach acid (gastric acid) and enzyme production, promoting digestion, while ghrelin (“the hunger hormone”) stimulates appetite, promotes growth hormone release, and increases food intake, with levels rising during fasting and falling after meals. They interact, as gastrin can trigger ghrelin release, and both can synergistically increase acid secretion, but generally, high gastrin correlates with lower ghrelin, and vice-versa, influencing energy balance.
