Swallowed chewing gum does not stay in your system for seven years. Gum, along with anything else inedible, passes from your mouth into the toilet in about a day or two, according to Dr. Michael Picco of the Mayo Clinic. Perhaps this misconception is popular due to the fact that gum is not easily digested and is also sticky. But take a sticky wad of half-chewed gum and sprinkle it with water and you'll notice it's not sticky anymore. Once you've swallowed the gum, it's not going to cement itself to your stomach wall because it has lost its stickiness in your stomach juices. If something did get stunk in your digestive track, you wouldn't survive seven years. Within days, stuck food becomes infected and makes you sick. Swallowing gum is about the same as swallowing rocks: they aren't toxic; they will leave your body in a few days; but they might do some damage along the way. Dr. Picco writes "On rare occasions, large amounts of swallowed gum combined with constipation have caused intestinal blockage in children. It's for this reason that frequent swallowing of chewing gum should be discouraged, especially in children." A far more dangerous non-toxic item to ingest is a pair of magnets. The magnetic fields themselves don't do any damage directly to your tissue, but the magnetic force between the magnets will cause them to stick together, with your tissue in the middle. And a few drops of water isn't going to turn off that kind of stickiness.