Microplastics and IBD: Does it Matter?

Microplastics are turning up almost everywhere researchers look - in our food and water, in indoor air and household dust, and now inside human tissues and organs.

So what does that mean if you, or your child, are living with Crohn's or ulcerative colitis? Could microplastics be adding to the inflammation - or are we simply finding more of them because the gut is already inflamed?

The honest answer, for now, is that it's not clear cut. However, the research is starting to show how microplastics and the gut interact, which is really insightful.

What are microplastics?

Microplastics are plastic particles smaller than five millimetres. Nanoplastics are smaller still - small enough, in some cases, to slip across barriers in the body that larger particles can't.

Some are made small on purpose. Most, though, are created through usual wear and tear - bottles, packaging, containers and synthetic fabric slowly breaking apart under heat, sunlight, friction and washing.

We take them in as we eat and drink, and breathe them in too. Synthetic clothing, household dust, food packaging, drinks bottles, chopping boards and plastic food containers are all potential sources.

Are there more microplastics in people with IBD?

One of the first human studies to look at this directly compared stool samples from people with IBD against those without. It found more.

The researchers found an average of 41.8 microplastic particles per gram of dry stool in the IBD group, compared with 28 in the control group. They also found that the more microplastic in the stool, the more severe the person's IBD tended to be.

At first glance, that sounds as though people with more active IBD are accumulating more plastic. But a stool result can't tell us that on its own.

A higher level in stool might reflect:

• greater exposure to microplastics

• altered movement of particles through the intestine

• changes to the mucus layer or microbiome

• reduced uptake into tissues

• or, the other way round, more effective elimination

The researchers themselves concluded that microplastic exposure might be tied up in the disease process, while also acknowledging that IBD could change how particles are held onto or passed out. An association, in other words - not proof of cause and effect.

What about the gut wall itself?

More recently, research has gone deeper - into the tissue.

A 2025 study looked at intestine and surrounding fat removed during ileal surgery from people with Crohn's disease. Microplastics were there inside the scarred, fibrotic tissue, and the more fibrosis they found, the more plastic came with it.

That matters, because fibrosis isn't fleeting surface inflammation. It's the slow thickening and remodelling of the gut wall that can, over time, lead to strictures.

Even so, the study leaves the central question open: did the plastic help drive the scarring, or is scarred, inflamed tissue simply better at catching and keeping hold of particles?

A very recent, small 2026 study also compared inflamed, eroded tissue with healthier tissue from the same people, it found significantly more micro- and nanoplastic in the inflamed areas.

Only six people were included, so it's early, preliminary evidence. But it does support the idea that damaged of inflamed tissue may be more prone to holding onto microplastic.

And that raises the possibility of a difficult cycle:

1. Inflammation and damage make it easier for particles to stick to, or enter, the tissue.

2. Those trapped particles stir up more oxidative stress and immune activity.

3. The gut becomes a little more vulnerable to the next round of exposure.

   
   

It's a plausible hypothesis, and indicates why microplastics might matter more in a gut that's already struggling than in one that isn't. It's one that researchers are now taking seriously.

I'll expand more on how microplastics specifically impact the gut, review the question often posted on how best to remove, and cover some ways to support rebuilding the damage they may cause in a later post. If you're keen to catch it, feel free to sign up to the newsletter here.

Reducing Microplastic Exposure - Where to Start

Here's the more reassuring part.

We can't draw microplastics back out of the body once they're in, and no one can honestly promise that lowering your exposure will change the course of IBD. But reducing what gets in - especially the things you do over and over - sits squarely within your control. And it's far less daunting than trying to live plastic-free.

The trick is not to try to do everything at once. Four small questions help you aim at what counts: is there heat involved, is there wear, how often does it happen, and how easy is it to change?

Start with heat

If you change one thing, make it this. Heat seems to be one of the biggest triggers for shedding: in a 2023 study, microwaving released far more micro- and nanoplastic from containers and pouches than chilling or storing at room temperature.

So, where you can:

• tip food into glass or ceramic before it goes in the microwave

• don't pour anything boiling straight into plastic

• let leftovers cool before putting in a plastic tub

• reach for glass or stainless steel for warm food

• skip reheating in takeaway containers

• don't put cling film over warm dishes

  
  

And a small myth worth retiring: "microwave-safe" only means the container won't warp or melt. It says nothing about the particles it might release.

Debunking "BPA free" too as a safe option. It only tells you one specific chemical is missing - and it's often replaced by a close relative (BPS, BPF) that isn't clearly safer - while telling you nothing about whether the container sheds microplastic.

Tea deserves its own mention. The soft, silky mesh bags shed a surprising amount the moment hot water hits them - one study counted billions of particles in a single cup, and in 2024 researchers watched particles like these being taken up by human gut cells in the lab. We don't yet know what that means for health, but if tea is a several-times-a-day ritual, swapping to loose leaf in a metal or glass strainer can be a small, easy change.

Then look at wear

Plastic that's scratched, cloudy or peeling sheds more than plastic that's smooth and new, and everyday scraping, cutting and hot washing all take their toll. Gentle steps here:

• retire containers that are visibly scratched or going cloudy

• keep the knife off plastic plates and tubs - a wooden board is kinder

• go easy on the hard scraping

• let disposable packaging be disposable, rather than a second lunchbox

Dishwashing releases particles too if plastic items are added. One 2025 study found a single full cycle can send around 920,000 plastic particles from the items washed into the wastewater - nearly a million per wash. It's mainly due to hot, abrasive cycles. Although most goes out with the wastewater, some is likely to be left across your crockery. The amount is likely small in comparison to other sources, however washing plastic items by hand can be an easy little win.

Notice what you use every day

A sandwich in a plastic wrap or cling film once in a while isn't a huge issue - though best avoid cling film with anything warm, or fatty. It's more the small, regular daily repeat exposures that add up, so worth having a quick check for some of these regular uses:

• a child's lunch reheated in the same plastic tub every school day

• batch cooking using plastic containers

• water carried in an old, scratched bottle (one 2024 study put the average litre of bottled water at around 240,000 plastic particles, most of them nanoplastics - reason enough to move to glass or stainless steel)

• plastic containers microwaved or dishwashed repeatedly

• hot food routinely sitting under cling film

• a well-worn plastic chopping board

  
  

Changing just one of those at a time, feels a lot more do-able.

Make the swaps that stick

None of this needs a spending spree or a single overwhelming afternoon. A few swaps that may help:

• glass or stainless-steel containers for anything you store and reheat

• a glass or steel water bottle

• greaseproof paper or a fabric wrap for sandwiches and dry snacks

• a plate over a ceramic bowl in the fridge, in place of cling film

• a wooden or composite board for chopping

  
  

Silicone can be a reasonable choice for some households, though it isn't quite as 'clean' it's sometimes sold as. Beeswax wraps are lovely for cold foods, but not for hot ones, and not for anyone with a bee allergy.

Keeping it all in proportion

It's easy to read something like this and want to bin every plastic item in the house by teatime. Honestly, that's not the message.

The bits it's important to remember:

• the research is real, and worth respecting: people with IBD have been found to carry more microplastic in their stool;

• plastic has turned up inside fibrotic Crohn's tissue;

• early evidence hints that inflamed tissue holds onto more;

• and everyday plastic items clearly shed particles as they're heated and worn.

• it's also recent findings, it can't yet tell us that microplastics cause IBD, or trigger flares.

So start with the easy wins. Keep plastic away from heat. Replace the things that are visibly falling apart. Look at the exposures your family repeats every day, and change one at a time.

You don't need perfection here - just a few steady changes that meaningfully lower your exposure.

A Few Questions I'm Often Asked

Do microplastics cause IBD?

There's no proof that they do. Microplastics have been found more often in people with IBD, and inside inflamed gut tissue, but that's an association rather than cause and effect - and an already-inflamed gut may simply hold onto more of them. For now it's a reasonable concern worth acting on gently, not an established cause.

Are microplastics more of a concern for children?

It's a fair worry, and not one the research has fully settled. Children eat, drink and breathe more relative to their size, and their bodies are still developing, so it makes sense to aim the easy swaps - heated plastic, daily bottles, lunch containers - at the things they use most. Less about alarm, more about keeping a lifelong exposure lower from the start.

Is tap water better than bottled water for microplastics?

In most studies, yes - bottled water tends to carry considerably more plastic than tap, some of it shed from the bottle and cap themselves. If your tap water is safe to drink, a glass or stainless steel bottle filled at home is usually cheaper and lower in microplastics. A simple carbon filter may reduce them further, though the evidence on filters is still mixed.

Are paper tea bags free from plastic?

Not always. Plenty of "paper" tea bags are sealed with a thin plastic around the edges, so they aren't automatically plastic-free - it is possible to check individual brands though. Loose leaf with a metal or glass strainer is the surest way round it, and a growing number of brands now use plant-based bags instead.

Which everyday foods carry the most microplastics?

Some of the most commonly reported sources are bottled water, seafood (especially shellfish eaten whole), tea from plastic bags, table salt, and anything heated or stored in plastic. You won't avoid every source, so it's more useful to ease off the ones you come across daily.

References

Yan, Z. et al. (2022) 'Analysis of microplastics in human feces reveals a correlation between fecal microplastics and inflammatory bowel disease status', Environmental Science & Technology, 56(1), pp. 414-421.

'Microplastic accumulation in fibrotic intestinal tissue and mesenteric adipose tissue in Crohn's disease patients' (2025), Environmental Research, 271, 121077.

'Higher abundance of micro- and nanoplastics in inflammatory tissues from patients with intestinal erosion' (2026), published online ahead of print.

Hussain, K.A. et al. (2023) 'Assessing the release of microplastics and nanoplastics from plastic containers and reusable food pouches: implications for human health', Environmental Science & Technology, 57(26), pp. 9782-9792.

Hernandez, L.M. et al. (2019) 'Plastic teabags release billions of microparticles and nanoparticles into tea', Environmental Science & Technology, 53(21), pp. 12300-12310.

Banaei, G. et al. (2024) 'Teabag-derived micro/nanoplastics as a surrogate for real-life exposure scenarios', Chemosphere, 368, 143736.

Okoffo et al. (2025) 'Release of Micro- and Nanosized Particles from Plastic Articles during Mechanical Dishwashing', ACS ES&T Water, vol 5 (6), pp. 2870-2881.

Qian, N. et al. (2024) 'Rapid single-particle chemical imaging of nanoplastics by SRS microscopy', Proceedings of the National Academy of Sciences, 121(3), e2300582121.

Zimmermann, L. et al. (2025) 'Food contact articles as source of micro- and nanoplastics: a systematic evidence map', npj Science of Food, 9, 111.