Lower abdominal discomfort with bad breath after lying down needs to consider dietary and disease causes. Dietary causes include eating too much meat, eating too much gas-producing food, etc. Disease causes include Helicobacter pylori infection, functional dyspepsia, and intestinal dysbiosis. 1. Dietary causes: if you eat too much meat food, the digestive burden increases, incomplete digestion of food can appear bad breath, bloating, belching (hiccups) and other symptoms; such as eating radish, onions and other gas-producing foods, can produce a lot of gas in the gastrointestinal tract under the action of digestion, the increase in exhaust, belching, hiccups and other symptoms. 2. Disease causes: such as Helicobacter pylori infection can have belching, bad breath, loss of appetite and other symptoms, can be clear through the breath test, gastroscopy and other tests; such as functional dyspepsia can have loss of appetite, belching and other symptoms, can be clear through the gastroscope, barium meal fluoroscopy and other tests; such as intestinal flora imbalance can be abdominal pain, diarrhea and other symptoms, combined with the routine stools, enteroscopy and other clear. For the cause of lower abdominal discomfort with bad breath after lying down, it is recommended to consult a doctor with the necessary tests to determine the cause.