Spitting is not a habit worth getting into for reasons that go beyond the obvious. Despite the social indignation of those who spit, there are also personal health hazards that need to be brought to your attention. Ulcers, cancers and the spreading of disease are major considerations when talking about the dangers of spitting. Mental issues, such as self image problems, can also become a contributing factor in developing a spitting habit.
Spreading of Disease
Saliva hosts a variety of diseases and infections. Spit contains your DNA, thus autoimmune diseases and bacteria are highly contagious in spit, as spit serves as a transit vessel from one host to the next. Spit that carries such infections must penetrate the body somehow and reach the bloodstream such as via an open sore, mouth or even an eye, in order to become deadly. Viruses such as meningitis are also easily transferable through spit. Other germs, such as the common cold and influenza, are significantly prevalent diseases spread by saliva.
Risking your acceptance in social situations, or reducing your public image, is a significant danger caused by spitting. Most public settings tolerate spitting to some degree.The stigma, however, is laid upon those who spit constantly. Common courtesy is recommended when considering spitting, but if you spit just because you can and do it all the time, beware: People notice and tend to take offense.
Chewing Tobacco and Spitting
People who use chewing tobacco and spit are also posing specific dangers to themselves and hose around them. According to the Stop the Spit website, "70 percent of people who use chewing and spitting tobacco get mouth sores, cracking and bleeding lips and gums, receding gums (which can eventually make your teeth fall out), increased heart rate, high blood pressure, and irregular heartbeats -- all leading to a greater risk of heart attacks and brain damage (from a stroke)." Chewing tobacco and the saliva within the mouth can cause oral cancer on the lips, tongue, the roof or floor of the mouth, the cheeks, or the gums. The tainted saliva can also send cancer agents into the lining of the stomach, esophagus and bladder.
Being spat upon is a humiliating experience, and if you are the one doing the spitting then you put yourself at risk legally. Public cases of spitting in the face of another person have lead many to question whether deliberate spitting onto another person should be considered a higher degree of assault. As of now, most spitting offenses are municipal charges, not amounting to much more than unpaid parking tickets in severity. However, court rulings are subjective, so if you spit on someone out of disdain, expect the possibility of a personal injury lawsuit or criminal complaint.
In exceptionally extreme cases, if you are infected with a life-threatening disease and it can be proven that you purposefully spit on someone to infect them, your saliva can be considered a deadly weapon. This is especially true if a case can easily be made based on the degree of premeditation involved in the act.