Microplastics Could Be Adding to Your Risk of Fatty Liver Disease

One of the planet’s most widely used plastics, found in food packaging, plastic wrapping, food storage tubs, and takeaway drink cups, could partly contribute to the risk of fatty liver disease.

Although the condition in its current definition was first identified in 1980, doctors had understood since the 19th century that fat accumulating in the liver was connected in some way to diet, well before formal research began.

Now, a mouse study indicates that modern food conveniences could be worsening the issue.

Fatty liver disease and its risk factors

Many people do not realise they have non-alcoholic fatty liver disease until it is discovered by chance during a scan for another health problem.

For those who do have symptoms, these can include tiredness, generally feeling unwell, and discomfort beneath the ribs on the right-hand side.

Fat can accumulate inside liver cells and, without treatment, may ultimately cause inflammation, fibrosis – a build-up of scar tissue – and even cirrhosis, which is severe damage.

Stages of fatty liver disease (now known as metabolic dysfunction–associated steatotic liver disease) progress from healthy liver tissue to steatosis (fat accumulation), inflammation, fibrosis, and cirrhosis. (National Institute of Diabetes and Digestive and Kidney Diseases/NIH)

The likelihood of fatty liver disease is higher for people carrying extra weight, particularly around their waist.

Further risk factors include elevated blood fats, such as LDL cholesterol or triglycerides; type 2 diabetes or prediabetes; and high blood pressure.

Each of these factors is linked to diet and metabolism. Yet the mouse study points to a potentially overlooked aspect of people’s diets: contact with microplastics, especially polyethylene.

Polyethylene microplastics and liver health

Polyethylene is among the plastics most central to convenient food consumption: it is used for takeaway packaging, wrapping leftover food, and preventing a disposable cup from breaking down in your hand.

Compared with many other polymers, however, polyethylene has generally been seen as less concerning.

"No studies have really looked into polyethylene's effect on liver health, and it's the most widely produced plastic," explains molecular pharmacologist Adi Joshi of Texas A&M University.

"What we now know is that these microplastics, especially polyethylene, affect our liver's natural defense and repair mechanisms."

The work by Joshi and colleagues, published in Science Advances, involved mouse experiments. More research is therefore needed before it can be established whether polyethylene affects human livers in the same, or similar, ways.

The mouse sample was also quite small, though the effects observed were nevertheless worrying.

How the mouse study tested polyethylene

The researchers divided twenty male mice into four groups.

A schematic overview of the experimental design showing the different treatment groups and analysis techniques. (Jung et al., Science Advances, 2026)

Mice in groups 1 and 2 received standard laboratory chow. Groups 3 and 4 were given a high-fat, high-sugar, high-cholesterol diet that is known to induce metabolic dysfunction-associated steatohepatitis, or MASH, the medical name for this form of fatty liver disease.

The team additionally administered water containing two milligrams of polyethylene particles, measuring between 10 and 150 nanometres across, every day to groups 2 and 4.

These regimens lasted eight weeks, after which the mice were euthanised and their blood serum and livers collected for detailed examination.

The findings indicate that tiny polyethylene particles may produce signs of fatty liver disease even in mice eating a standard diet.

As anticipated, the two groups on the MASH diet scored much higher for indicators of fatty liver disease than the groups receiving standard chow.

But adding microplastics seemed to aggravate the condition regardless of diet, including in mice that had eaten a comparatively healthy diet.

Both groups given microplastic-containing diets had higher levels of ALT – an enzyme that signals poor liver health – and liver triglycerides than animals given the equivalent diet without polyethylene.

Liver-cell inflammation and ballooning were likewise increased, as was steatosis, the accumulation of fat in the liver.

Molecular and histopathological effects of polyethylene microplastics in mouse liver with or without a high-fat diet. (CD = control diet, Veh = vehicle [water with no microplastics], MD = MASH diet, PE = polyethylene). (Jung et al., Science Advances, 2026)

Using spatial transcriptomics on the mouse liver samples, Joshi’s team examined genetic signals for proteins made in response to microplastics.

Genes that encode the proteins PPAR-alpha, which controls liver-fat production, and Annexin A2, which helps repair liver tissue, were both highly active in livers affected by microplastics.

Larger studies are clearly required, but the evidence so far suggests that polyethylene microplastics and an unhealthy diet could each play a role in fatty liver disease developing – particularly when they occur together, as they frequently do.

Related: A Common Cholesterol Treatment May Also Remove PFAS And Microplastics From Blood

"Those who have a more Western-style diet, including foods like burgers and sodas, may have a greater chance of progressing to fatty liver disease if they are also exposed to polyethylene," Joshi says.

The research appeared in Science Advances.

This article was fact-checked by Rachel Garner and edited by Clare Watson. While we take pride in our process, we are only human. If you spot an error, please let us know.