|Vomiting is the involuntary action of the body to empty the contents of the stomach through the mouth. Vomit is made up of half-digested food from your stomach, stomach mucus, saliva, stomach acids and other chemicals that help you digest food. Bile is green in color – which is why vomit is usually yellowy green in color. Bile is not created in your stomach, it is created in the intestines - when an individual vomits the bile comes from further down in the digestive system. The nasty smell associated with vomiting can also be blamed on bile and stomach acids.