An apparatus and method for treating morbid obesity in mammals using a gastric reduction assembly that reduces the gastric volume of a stomach and induces early satiety. The gastric reduction assembly comprises at least two or more expandable devices, each able to be adjustably inflated with a fluid (e.g., a liquid or a gas) using a filling tube. In a preferred embodiment, the gastric reduction assembly is inserted through the abdominal wall and placed at a location exterior to the stomach body, avoiding an abdominal incision. Once positioned near the stomach body, the gastric reduction assembly allows for the external compression of the stomach body to limit food intake. The gastric reduction assembly also minimizes the potential for shifting of the expandable devices after insertion to the stomach body to revert to its pre-compressed state.