Loss of appetite nausea and vomiting may be caused by the following reasons: 1, indigestion, due to irregular diet, poor eating habits lead to. Daily life should pay attention to strengthening physical exercise to promote the peristalsis of the gastrointestinal tract to help digestion. Usually pay attention to eat less, avoid overeating; 2, pregnancy vomiting, also to exclude pregnancy pregnancy reaction; 3, hypertensive patients will also appear these nausea, vomiting, loss of appetite, but its often accompanied by dizziness, headache; 4, a variety of gastric diseases can also lead to, such as pyloric stenosis or pyloric obstruction, will also appear loss of appetite, nausea and even vomiting symptoms; 5, long-term constipation. Due to the inability to pass stool, these symptoms of nausea, vomiting, loss of appetite can also occur; 6, renal disease, renal insufficiency, will also appear these symptoms. If you want to further clarify the cause, you need to go to a regular hospital for examination.