This invention is an expandable intragastric device for reducing food consumption and/or absorption. In an example, this device can be embodied in a plurality of longitudinal expandable members which are arranged in a colonnade configuration to form a restrictive food lumen within a stomach. Pumping a flowable substance between the interiors of these expandable members changes the rate of food flow through the stomach, the capacity of the stomach to hold food, and/or the amount of food absorbed by the body. This offers some of the beneficial effects of gastric sleeve surgery, while also being adjustable and reversible.