There are several cases of coffee stomach pain: 1, poor gastrointestinal function, coffee can stimulate the stomach to secrete more gastric acid, if the gastrointestinal is not good, such as gastritis, enteritis, gastric ulcer and other diseases, coffee will stimulate the gastric mucosa, will make the secretion of gastric acid increase, drinking coffee will stomach pain. 2, a one-time drink too much coffee, coffee can promote gastrointestinal peristalsis, improve the digestive capacity of the gastrointestinal, for many people The coffee can help promote defecation, if you drink too much coffee at once after the gastrointestinal stimulation will lead to stomach pain. 3, fasting coffee on the gastrointestinal stimulation is stronger, will affect the digestion and absorption function of the gastrointestinal, especially long-term fasting coffee will have the possibility of inducing gastric disease, so it will lead to stomach pain. 4, drinking expired coffee or coffee contaminated, because the coffee was a bit bitter. So spoiled is not easy to be found, but spoiled coffee contains a lot of bacteria, drinking it will easily lead to tummy ache.