New Study Reveals Chewing Gum May Release Microplastics into Saliva

If you enjoy a refreshing stick of gum occasionally, you might want to pause and reflect on what you’re really consuming.

A recent pilot study conducted by researchers from the University of California, Los Angeles (UCLA) discovered that chewing gum, including varieties labeled as natural, could release hundreds to thousands of microplastics into the human body.

Graduate students Lisa Lowe and Jamie Leonard, alongside Sanjay Mohanty, an associate professor of civil and environmental engineering at UCLA, presented their findings at the American Chemical Society’s 2025 meeting held in San Diego last month.

Mohanty explained that plastic products are a part of our daily lives, from containers to bottles. He noted that over time, these plastic items fragment into tiny particles, invisible to the naked eye, which are termed microplastics.

The Research Background

In their study, researchers analyzed ten different brands of chewing gum currently available on the market, consisting of five synthetic and five natural varieties.

However, the brands tested were not disclosed in their findings.

The composition of most chewing gums includes a rubbery base, flavorings, and various sweeteners. Mohanty highlighted that the chewy texture of gum results from a polymer, which is similar to a plastic-like substance.

Natural gum products are typically made from plant-based polymers, leading many consumers to believe they contain less plastic than synthetic counterparts. Yet, the UCLA researchers found an unexpected outcome — even the natural gums released microplastics.

Unexpected Findings

The significant revelation from this study was the comparable amounts of microplastics released from both natural and synthetic gums. Lowe expressed her surprise, stating that the team initially hypothesized that natural gum products would be free of plastic.

This assumption proved incorrect, as both types of gum exhibited similar microplastic release levels during the study. The polymers identified in the gums included polyolefins, polyethylene terephthalates, polyacrylamides, and polystyrenes, suggesting that the manufacturing process or packaging might contribute to this contamination.

Study Methodology

For the study, participants chewed seven pieces of gum from each brand, one at a time. Each person was instructed to chew for four minutes, enabling them to produce a saliva sample reflective of the chewing process.

The analysis revealed an average release of 100 microplastics per gram of gum, with some variants releasing as many as 600 microplastics per gram. Mohanty stated that this translates to an estimated 200 to 250 microplastics per typical piece of gum.

Health Implications of Microplastics

Currently, the scientific community lacks comprehensive knowledge about the health impacts of microplastics on humans. Mohanty noted that plastics have been in common use for only 50 to 70 years, leaving a gap in the understanding of their long-term effects.

While the dangers of exposure to substances like asbestos are well-documented, the health consequences of microplastics remain unclear. Mohanty acknowledged growing evidence indicating that microplastics have accumulated in human bodies but emphasized that we do not yet know what this accumulation means for overall health.

Industry Response

A spokesperson for the National Confectioners Association (NCA), based in Washington, D.C., emphasized that food safety is the top priority for confectionery companies in the U.S. They use only ingredients approved by the Food and Drug Administration (FDA).

The NCA pointed out that the authors of the pilot study themselves stated there is no immediate cause for alarm, asserting that gum has been enjoyed safely for over a century.

Moving Forward

The findings of this study may provoke consumers to reconsider their choices when reaching for a stick of gum. While the research primarily serves as a pilot study, it raises essential questions about what is being ingested through seemingly benign everyday products.

Future research is necessary to gain a clearer understanding of how microplastics might affect human health over time. As awareness grows about the presence of microplastics in various products, including food items like chewing gum, consumers are likely to become more mindful of their dietary choices.

While chewing gum may still be viewed as a harmless indulgence, this study reminds us that even familiar products can introduce unexpected health considerations.