Nausea at the sight of food is related to indigestion, overwork, gastrointestinal diseases and pregnancy. Each person’s body is different, some people do not pay attention to diet will lead to indigestion, food intake into the stomach can not be quickly emptied, will cause pressure on the stomach wall causing abdominal distension, there will be nausea when you see the meal. Usually should pay attention to the combination of work and rest, such as high-intensity exercise, heavy physical labor, will lead to physical fatigue, will have an impact on the digestion of the gastrointestinal tract, will also appear to see the meal on the stomach upset. Frequently eating stimulating food, smoking, drinking will cause irritation to the mucous membrane of the stomach, causing gastritis, gastrointestinal ulcers, and there will be loss of appetite and indigestion. Previously ingested food can not be emptied quickly in the stomach, and when you see food again, you will feel upset stomach. The increase in hormone levels after pregnancy will cause irritation to the gastrointestinal tract, causing stomach upset. Women of childbearing age who experience stomach upset, nausea, and vomiting are considered to be caused by pregnancy.