Embodiments of the invention provide apparatus and methods for stimulating L cells in the intestinal tract to produce incretins for the treatment of conditions including diabetes and obesity. Many embodiments provide a method and apparatus for the treatment of diabetes by electrically stimulating L-cells to secrete incretins to stimulate or otherwise modulate the production of insulin. Particular embodiments provide a swallowable capsule for stimulating L-cells in the intestinal tract as the capsule moves through the tract. The capsule can include two or more electrodes for providing electrical stimulation to L-cells, a power source for powering one or more components of the capsule, a sensor for sensing the location of the capsule in the intestinal tract; a controller and a waveform generator for generating the electrical signals emitted by the electrodes to stimulate the L-cells to secrete incretins such as GLP-1 to stimulate insulin production for glucose regulation of diabetic conditions.