Many MindedMice on fiber-rich diets flushed out ingested plastic faster
A study in mice, published October 15 in Nature Communications, reports that a high-fiber diet reduced the buildup of plastic particles in the intestines. The paper is titled "High fiber diet mitigates exposure risk of nanoplastics in male mice." Z. Yu is the lead author in the citation, and environmental scientist Eddy Y. Zeng of South China University of Technology in Guangzhou discusses the work.
Researchers put mice on low-, medium- or high-fiber diets and then fed them plastic particles. Within 24 hours, mice on medium- and high-fiber diets had cleared more particles from their bodies than the low-fiber group. After a week of daily plastic feedings, gut tissue damage showed up only in the low-fiber mice. Test-tube experiments suggest fiber physically wraps around and sticks to plastic particles. Zeng's hypothesis is that fiber forms a polymer network that traps the plastics so they pass out of the body.
Why it matters: plastic particles are now part of the human exposure picture. Earlier research has linked them in human arteries to higher risk of heart attack and stroke, and mice that ingest tiny plastic bits can show signs of organ injury. Fiber is cheap, widely available and already known to lower cholesterol, help control blood sugar and ease movement of food through the gut. If the effect holds in people, a basic food could become a low-cost defense against a pollutant that is otherwise hard to avoid.
The caveats are large. This was done in mice, and it is too soon to say whether fiber does the same in humans. The high-fiber mice ate far more fiber than people are advised to, so the amounts are not realistic. It is also not completely clear what micro- and nanoplastics do to human health. Zeng says that even if fiber does not purge plastic from human guts, eating more would probably do no harm. Watch for human studies using realistic doses.
Source: Science News