What Goes In Must Come Out: The Myth Behind Swallowed Chewing Gum


We’ve all done it. As we’re blissfully chewing our favorite flavor of chewing gum, whether it’s a sudden surprise, a hiccup or a stumble, down goes the gum. And as that moist little chunk of chewable delight falls into our stomachs, that old schoolyard adage is sure to run through our minds: It takes seven years to digest a piece of gum. Oh, dear. What now?

The good news is there simply isn’t an ounce of truth to the urban legend. First of all, gum can’t be digested in seven years, because most of its components—any number of natural or synthetic elastomers, or rubberlike materials—are completely indigestible, period. The stomach simply doesn’t contain enzymes to break it down. So whether it’s there for seven minutes or seven years or seven decades, you’re not digesting that gum. But that doesn’t mean it stays in your body, either.

Think about it. There’s something else we are all familiar with that’s also indigestible: Corn kernels. The outer covering of the corn kernel remains largely intact in the digestive tract. But what happens to it? You got it… it comes right out on looking much as it did going in. Same concept with gum. Although the flavorings, sweeteners and softeners used in chewing gum are easily digested, the gum’s base is treated as any other waste product—out through the poop shoot.


Granted, there’s always an exception to the rule, which is probably where the old wives’ tale originated. For example, the journal Pediatrics once highlighted a case where a child consistently swallowed gum—five to seven pieces daily over several years—resulting in a “taffy-like trail of fecal material” that had to be suctioned out of his rectum. Another child swallowed four coins after a large amount of gum, and the coins fused into a wad in her esophagus, held together by the blob of chewing gum. But for the most part, doctors never see hunks of chewing gum show up in colonoscopies or capsule endoscopy procedures unless they’ve been there less than a week—and even that is rare.

Still, it may be such rare horror stories—albeit caused by poor gum-chewing etiquette—that led to the seven-year myth. After all, people have had a hunkering to chew for thousands of years. Researchers have found 7,000-year-old lumps of tar with human teeth marks in them. Our modern chewing gum can be traced back to a rural practice in Maine. Around 1848, John Curtis observed local loggers chewing spruce resin and a business idea was born. He extracted resin, then boiled, skimmed, poured, cooled, rolled and cut it, before dusting it with cornstarch and wrapping it. Curtis priced the “gum” at one penny for two pieces—quite the price in those days. Unfortunately for the State of Maine Spruce Gum company, the paper industry didn’t leave enough trees for a steady supply of spruce resin, and the industry never fully took off.

Enter exiled Mexican general Antonio Lopez de Santa Anna—of Alamo fame—who introduced the rain-forest tree resin known as chicle to New York inventor Thomas Adams in the 1860s. It may have taken a while longer, but boxes of Chiclets bear Adams’ name to this very day. Who knows, maybe if Santa Anna had swallowed a few dozen hunks of chicle every day before that infamous time in 1836, it might have been a very different history for Texas.