Microplastics in Chewing Gum: What the Pilot Study Found

Chewing gum is a small daily habit that rarely receives a materials-science audit. A 2025 pilot study from UCLA changed that. The researchers tested commercially available gums and found that particles identified as microplastics could be released into saliva during chewing.^{[1] [2]}

The useful question is not “Is every piece of gum dangerous?” The useful question is what the experiment actually measured, what it could not measure, and whether it gives people a proportionate way to think about a routine exposure.

What did the researchers test?

The UCLA team examined 10 gum brands: five described as synthetic and five described as natural. For each brand, a single participant chewed seven pieces for four minutes while researchers collected saliva samples at regular intervals. In a separate test, they sampled saliva over 20 minutes to examine the timing of particle release. The team used microscopic counting and Fourier-transform infrared spectroscopy, a technique that can help identify polymer composition.^[1]

This design matters. It was a pilot study, meaning it was designed to produce an early signal and refine future questions. It was not a large population study, a clinical trial, or a test of whether chewing gum causes a health condition.

What did the study find?

On average, the researchers reported about 100 particles per gram of gum, with some individual samples reaching roughly 600 particles per gram. A typical piece of gum may weigh two to six grams, so the reported result was sometimes translated into a per-piece estimate. The researchers also observed that 94% of the collected particles were released during the first eight minutes of chewing.^{[1] [2]}

One of the more interesting findings was that the natural and synthetic gums released similar amounts in this experiment. That doesn't mean every gum is the same or that “natural” labels are meaningless. It means that, under these study conditions, a broad marketing category was not a reliable shortcut for predicting the measured result.

What the study cannot tell us

The team could identify particles 20 micrometers wide or larger. Smaller particles, including nanoscale particles, were outside the detection range. That means the study is not a complete particle inventory. At the same time, the small number of brands and the use of one participant mean the result needs replication before anyone treats it as a stable estimate for the entire gum market.^[1]

Most importantly, the research did not measure whether the particles were absorbed, how they moved through the body, or whether they produced a health effect. The UCLA researchers were clear on this point: there are no human trials showing that gum-derived microplastic particles cause a disease or other health outcome.^[2]

How to use the finding without turning gum into a fear trigger

The bigger context: exposure science is still developing

Researchers continue to investigate microplastic exposure through food, drinking water, air, and consumer products. Measurement is difficult because methods differ by particle size, material, sampling process, and laboratory technique. A World Health Organization report emphasizes that better data and standardized methods are needed to characterize exposure and potential implications for health.^[3]

That uncertainty is not a reason to ignore early findings. It is a reason to describe them accurately. A pilot study can be useful when it helps identify a previously overlooked source and shapes more rigorous research. It is less useful when a headline turns a measured particle count into a claim of proven harm.

A steadier way to think about daily habits

If gum is an occasional pleasure or a tool you use for fresh breath, this study doesn't require an all-or-nothing response. You might decide to chew less often, keep a single piece longer rather than replacing it early, or simply wait for stronger evidence. The right choice is the one that fits your needs without making a small exposure question dominate your day.

Sifts takes the same practical approach to microplastic awareness. Sifts is formulated with chitosan and dietary fibers that interact with particles during digestion and support the body’s normal elimination processes.* It is intended as part of a broader, realistic routine—not as a replacement for medical care or a promise about a particular consumer product. You can also explore Sifts’ practical guides to reducing everyday exposure, a cleaner coffee routine, and plastic kettles and hot drinks.

Frequently asked questions

Sources

[1] American Chemical Society. “Chewing gum can shed microplastics into saliva, pilot study finds” (2025).

[2] UCLA Newsroom. “Bursting your bubble: Chewing gum releases microplastics into your saliva” (2025).

[3] World Health Organization. Dietary and inhalation exposure to nano- and microplastic particles and potential implications for human health (2022).

[4] Lamoree et al. “Health impacts of microplastic and nanoplastic exposure.” Nature Medicine (2025).