What harmful things do spit contain?

Saliva can contain harmful substances such as bacteria, viruses, and fungi that may lead to infections. It can also carry traces of food particles and toxins, including heavy metals, if ingested. Additionally, certain diseases can cause saliva to harbor pathogenic microorganisms, which can be transmitted through activities like sharing drinks or kissing. Overall, while saliva has protective functions, it can also pose health risks if contaminated.