The invention relates to a gastric restraining device for treating excessive weight or obesity in mammals. The gastric restraining device includes an elastomeric sheet configured to be placed around a stomach of a mammal, an ablation device attached to the elastomeric sheet, the ablation device configured to emit energy toward an outer surface of the stomach when the elastomeric sheet is placed around the stomach, and an energy device coupled to the ablation device to generate the energy and to transfer the energy to the ablation device.