A patient is provided with an increased sense of satiety by increasing resistance to the outflow of food from the stomach and through the intestines. Stomach emptying may be slowed with devices implantable within the gastrointestinal tract below the stomach. Implants are preferably removable and can include artificial strictures or apertures that may be adjustable or elastic to vary the rate of stomach emptying. Slowing gastric emptying may induce satiety for a longer period and may therefore reduce food consumption. Many of the embodiments include intestinal sleeves or sleeves, but they need not. The resistor concept may be applied to a simple anchor and resistor without a long sleeve.