It's a difficult truth to swallow, but research shows that, every year, we consume between 39,000 and 52,000 microplastic particles with our food.
It’s enough to give you a kind of cognitive indigestion. How, in this age of food safety and nutrition, can we be pigging out on plastics when unappetising studies show they’re probably harming our short- and long-term health?
One 2024 study looked at the plastics found in a range of 16 sources of protein in US diets. It found that from those foods alone, the average meal contained between 74–220 microplastic particles.
That’s not counting the flecks that come from our drinks bottles or food containers. It doesn’t account for the plastics that break off our cookware and end up on our plates, either.
Microplastics have also been found in drinking water, salt, rice, honey and powdered supplements. They leach from teabags and chip off plastic chopping boards. Even fruit and vegetables contain microplastics absorbed through their roots from contaminated soil and water.
Plastic is everywhere in our food system and research is only beginning to give us a clear idea of how it affects us.
Studies have shown links between microplastic exposure and increased risk of cardiovascular disease, some cancers and metabolic conditions.
As well as physically damaging our tissues, they can cause inflammation, cause changes to our microbiome and expose us to harmful chemicals such as per-and polyfluoroalkyl substances (PFAS), phthalates and bisphenol A.
There’s a morsel of optimism, however. Researchers are beginning to wonder if dietary fibre can lower the amount of microplastics accumulating in our digestive systems.
A 2024 paper speculates that fibre’s absorbent properties may allow it to bind to microplastics in the gut, allowing us to secrete them in greater quantities – plastic poo in your toilet bowl, in other words.
The idea is that soluble and insoluble fibres form a gel-like barrier that stops microplastics from crossing the intestinal wall and entering the bloodstream. With nowhere else to go, plastics are swept along with other waste.
This mechanism has not been studied or directly observed in humans as yet, but in 2025, a research team in Japan did show something similar working in rats.
Scientists at Tokai University fed rats a selection of indigestible dietary fibres mixed with microplastics. They found that rats fed with a type of fibre called chitosan excreted significantly more microplastics than others.
“We confirmed that chitosan binds to microplastics,” says study author Prof Muneshige Shimizu. “We believe it could be utilised in any food where the chitosan structure can be maintained.”
Shimizu says that not every type of fibre they tested did the same thing, so further research is needed to figure out which specific structures are effective.
In the meantime, there may be other ways that fibre reduces the health toll from microplastics. Researchers at Boston University in the US found that in mice, a fibre supplement could flush out PFAS, the so-called forever chemicals that plastics are often treated with.
Researchers found that gel-forming fibres act as a kind of magnet for PFAS in the gut, again helping to direct them out of the body.
But before you stockpile a year’s worth of Weetabix, it’s important to note that researchers are still working to understand which kinds of dietary fibres help to flush out plastics and PFAS.
Nevertheless, increasing your fibre intake is generally recommended for a wide range of health reasons, from cardiovascular health to cancer risk reduction.
Although microplastics are unavoidable in the modern world, there are other ways to lower the amount you’re exposed to in the kitchen.
Dr Lisa Zimmermann is from the Food Packaging Forum, a non-profit foundation that researches how chemicals from packaging affect what we eat.
She tries to minimise the plastics she’s exposed to by getting fruit and vegetables from farmers’ markets and avoiding things like disposable cups lined with plastic.
She also avoids microwaving plastic containers. “The heat leads to faster particle movement and particle release,” she says. “I use glass or ceramic instead.
“You can’t completely avoid plastics, but I try to at least reduce them.”
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