Traditional chewing gums were made from the rubbery saps of different trees. The Manilkara zapota tree was a favorite, as it produces a thick gum-like latex called chicle. This was known to have medicinal properties, and was used as an astringent to help digestive difficulties. Chicle contains sapotin, saponins, tannins and resins, among other constituents (Kulkarni et al. 2007).
Other traditional societies chewed rubbery saps for medicinal reasons. Spruce tree resin was chewed for centuries. Resin from the mastic tree was chewed by the Ancient Greeks. Betel nuts have been chewed for thousands of years, although some would contend that this is not a gum.
Today, most chewing gum utilizes a synthetic rubber called polyisobutylene. Polyisobutylene is produced from the polymerization (chemical bonding) of isoprene and isobutylene (a hydrocarbon derived from petroleum). Polyisobutylene is also called butyl rubber. Butyl rubber is used in sealants, lubricants, caulking agents and adhesives. Much of the world’s supply of polyisobutylene comes from oil companies.
Various refined sugars and artificial colors and flavors may also be added to chewing gums. Maybe not so healthy either.
Chewing gum also utilizes harmless softeners such as glycerin, a vegetable oil. This keeps the gum from becoming hard.
The bottom line is that unless it is a natural chewing gum that uses chicle with xylitol, chances are, that gum is not so healthy to swallow, or even chew, for that matter.
And as for the legend that swallowed gum stays in the stomach for seven years: Urban (mother’s) legend. Even the synthetic rubber will be broken down by the stomach’s powerful gastric acids and enzymes, and further broken down by the bile salts secreted into the intestines.
The question is what happens to the butyl polymers that are broken down from the synthetic rubber. Will these be assimilated into the bloodstream where they can potentially damage the liver?
In other words, there was good reason for Moms to perpetuate this myth about swallowing gum. They didn’t want us to have to swallow synthetic rubber.
Kulkarni AP, Policegoudra RS, Aradhya SM.Chemical composition and antioxidant activity of sapota (Achras sapota Linn) fruit. Jnl Food Biochem. 2007; 31(3):399-414