8-month-old babies with bad breath can be seen in the following situations: 1, the most common is that oral hygiene is not good, under normal circumstances, you should wash the baby’s mouth 2-3 times a day. 2, pay attention to the baby may have chronic oral and throat diseases, such as stomatitis, oral ulcers or chronic pharyngitis, etc. 3, pay attention to the baby whether there is a food allergy or lactose intolerance, because food allergy or lactose intolerance, poor digestion, increased gastrointestinal gas prone to bad breath. The baby may have chronic gastric disease, especially parents or siblings who have Helicobacter pylori infection at home may infect the baby and cause Helicobacter pylori infection, leading to the occurrence of gastrointestinal diseases and halitosis. 4.