How long does someones saliva stay in your system after kissing?

Answer 1

OK, so this is a really interesting question! So short answer It depends on what you mean by 'in your system'. You will never get a significant amount of their saliva in your blood stream or anything like that, because 1. You are not swallowing but a really small amount like maybe 10 ul. 2, The HCl in your stomach will obliterate 99.99% of anything in it, so it will not be 'their saliva' when what little is absorbed.

Now on the contrary, you will absorb some REALLY small amount of the matter from their saliva which will not really be their saliva anymore, but the actual water and so forth will be there. It will slowly diminish over the course of years if ever will be where every last atom of it is gone. That and the bacteria some strains new to your mouth will colonize and change the composition of bacteria in your mouth. But this is actually good for your teeth and immune system. Especially if you kiss a few friends.

By the sound of it you probably don't like my answer, but better to answer with integrity than tell a lie!