Can microplastics in food cause muscle wasting or muscle weakness?
Not proven in people. A 2026 lab study found polystyrene microplastics changed muscle-cell pathways tied to protein building and muscle atrophy.
What's actually in it
Polystyrene microplastics can come from disposable cups, food containers, and other plastic food-contact items. Food and drink are one way people can be exposed.
Muscle cells need steady energy and protein building to stay strong. When those systems are disrupted in the lab, muscle cells show signs linked with atrophy.
What the research says
A 2026 study in Toxicology exposed C2C12 muscle cells to 1 micrometer polystyrene microplastics for 24 hours. The study found higher reactive oxygen species, lower ATP production, mitochondrial damage, and lower IGF-1-PI3K-Akt-mTOR signaling.
The same study found higher levels of muscle atrophy markers, including myostatin, atrogin-1, and MuRF1. It also found lower markers tied to muscle protein building.
This was a cell study, not a human diet study. It does not prove that eating food from plastic containers causes muscle loss. It does support lowering avoidable polystyrene exposure, especially from hot food and drinks.