Abstract: The present invention features methods for applying a force, such as laser or radiofrequency (RF) energy to the wall of the small intestine, which targets and eliminates a portion of the capillary and vascular network responsible for the transportation of nutrients to the patient. This causes the patient to absorb a reduced percentage of nutrients, which results in a reduced caloric intake. Various types and shapes of applicators are used to deliver the treatment energy, and these applicator devices are within the scope of the present invention. The applicator can be deployed through either a body cavity (e.g., the oral cavity), an open surgical procedure, or a minimally invasive incision or incisions.