Love chewing gum? You may actually be munching microplastics, finds study

Chewing gum releases thousands of tiny plastic pieces straight into people's mouths, finds a study

Think chewing gum is harmless? Think again. A new study has found that every chew releases thousands of tiny plastic particles—called microplastics—into people’s mouths, which they unknowingly swallow.

 

The findings were presented at the American Chemical Society’s Spring 2025 meeting in San Diego. Researchers said both synthetic and natural gums are hidden sources of microplastic ingestion. A typical piece of gum sheds thousands of plastic particles per chew, adding to the tens of thousands of microplastics we consume each year, the study titled Chewing Gums: Unintended sources of ingested microplastics in humans noted.

 

“Our goal is not to alarm anybody. Scientists don’t know if microplastics are unsafe to us or not. There are no human trials. But we know we are exposed to plastics in everyday life, and that’s what we wanted to examine here,” said Sanjay Mohanty of the University of California, Los Angeles (UCLA), who led the study.

 

 

What are microplastics?

 

Microplastics are polymer fragments measuring between less than 5 millimetres (0.2 inch) and 1 micrometre (1/25,000th of an inch) in size. Anything smaller than this range is referred to as nanoplastics, which are measured in billionths of a metre.

 

What have the researchers found?

 

Lisa Lowe, a doctoral researcher at UCLA, chewed seven pieces from each of 10 chewing gum brands. The team then conducted a chemical analysis of her saliva.

 

The findings showed that one gram of gum released, on average, 100 microplastic particles—some samples shed over 600. With most chewing gums weighing between 2 and 6 grams, a larger piece could release up to 3,000 plastic particles. Most of these microplastics separated from the gum within the first two minutes of chewing.  ALSO READ | Microplastics in all Indian salt, sugar brands: How much are you consuming? 

Researchers pointed out that the most common chewing gum sold in supermarkets is made from synthetic gum, which contains petroleum-based polymers for that signature chewiness. However, packaging typically avoids mentioning plastics, using vague terms such as “gum-based.”

 

Although many assume synthetic gums are the worst offenders, the study revealed that even plant-based “natural” gums released similar amounts of microplastics. “Surprisingly, both synthetic and natural gums had similar amounts of microplastics released when we chewed them,” Lowe said.

 

The study, which is currently under peer review, estimates that individuals who chew about 180 pieces of gum annually could be ingesting close to 30,000 microplastic particles.

 

Mohanty added that this number is modest compared to the total microplastics humans are exposed to from other sources.

 

How else do microplastics enter our bodies?

 

Other studies have shown that microplastics are present in various household items such as chopping boards, clothing, and cleaning sponges. Researchers have detected microplastics throughout the human body—including the lungs, bloodstream, and brain—raising concerns about their long-term health impact. With the average person chewing hundreds of pieces of gum each year, the additional exposure could be significant.  ALSO READ | Microplastics found in blood, linked to heart disease & stroke risks: Study

 

Beyond ingestion, gum also contributes to rubber pollution, especially when disposed of irresponsibly in public spaces. “The plastic released into saliva is a small fraction of the plastic that’s in the gum,” Mohanty said. “So, be mindful about the environment and don’t just throw it outside or stick it to a wall.”

 

Researchers continue to detect microplastics everywhere—from mountaintops and deep oceans to the air we breathe.

 

Gum manufacturers respond

 

According to a report by AFP, the National Confectioners Association, which represents chewing gum manufacturers in the United States, said the study’s authors had acknowledged “there is no cause for alarm.”

 

“Gum is safe to enjoy as it has been for more than 100 years,” the group said, adding that all ingredients are approved by the US Food and Drug Administration.