Body shaking when hungry is related to duodenal ulcer, hypoglycemia, hyperthyroidism and other factors. During hunger the stomach glands secrete large amounts of stomach acid due to cues from the cerebral cortex, and once there is no food to neutralize it, the stomach acid will be squeezed into the duodenum. Some people who have duodenal ulcers themselves can suffer from severe pain caused by the erosion of stomach acid. The pain of duodenal ulcers is relatively intense and some people may experience shaking as a result. Some people have hypoglycemia, and once they are hungry, they may experience dizziness, headaches, and weakness due to the lack of sugar in the body to support the energy of the vital organs. Hyperthyroidism is a hypermetabolic disease that consumes a lot of energy in the body. People who suffer from hyperthyroidism are not only prone to hunger, but also suffer from shivering when they are hungry because their organs lack energy to support them.