Burping (also called belching and eructation) is the release of gas from the upper digestive tract (esophagus and stomach) of animals through the mouth. It is usually audible. In humans, burping can be caused by normal eating processes, or as a side effect of other medical conditions. There is a range of levels of social acceptance for burping: within certain context and cultures, burping is acceptable, while in others it is offensive or unacceptable. Failure to burp can cause pain or other negative effects. Humans are not the only animals that burp: it is very common among other mammals. In particular, burping by domesticated ruminants, such as cows or sheep, is a major contributor of methane emissions which cause climate change and negatively impacts animal agriculture on the environment. Significant research is being done to find mitigation strategies for ruminant burping, i.e. modifying the animals diets with Asparagopsis taxiformis (red seaweed). Causes
Burping is usually caused by swallowing air when eating or drinking and subsequently expelling it, in which case the expelled gas is mainly a mixture of nitrogen and oxygen. Burps can be caused by drinking beverages containing carbon dioxide, such as beer and soft drinks, in which case the expelled gas is mainly carbon dioxide. Diabetes drugs such as metformin and exenatide can cause burping, especially at higher doses. This often resolves in a few weeks. Burping combined with other symptoms such as dyspepsia, nausea and heartburn may be a sign of an ulcer or hiatal hernia, and should be reviewed by a physician.
Histiocytic sarcoma is a tumor derived from histiocytes. The tumor is often positive for CD163 and can appear in the thyroid. However, in some cases it can also appear in the brain. References


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