If the human body ages prematurely, the following symptoms will occur: 1. Symptoms of the digestive system include loss of appetite and poor appetite, such as acid reflux, heartburn, hiccups or abdominal distention, constipation, etc. These are all symptoms of premature aging of the digestive system. 2. 3. In the case of early aging of the nervous system, there will be obvious disorders of plant nerve function, such as poor quality of rest and sleep, or easy to wake up, dreamy, deep sleep phase shortened significantly, and difficulty in falling asleep, all of which are symptoms of early aging. 4. In the case of the circulatory and respiratory systems, there is a reduced ability to fight infection, easy fatigue, and easy to catch a cold.