The dark side of your dishwasher and how it leaks toxic chemicals into your bloodstream: Expert raises alarm on what the machines really do to your body, which types are the worst – and why your gut may never recover

‘Are your dishwashing tablets literally punching holes in your gut lining?’ – and ‘They are damaging your gut lining and leaking… into your bloodstream,’ says @timbiohacker on TikTok.

Meanwhile @nontoxicdad claims ‘Dishwasher detergents don’t just rinse away. Residue can cling to your dishes, exposing you to harmful chemicals with every meal.’

Or there’s @whichuk: ‘Stop using TOXIC rinse aids in your dishwasher – here’s why: Most rinse aids contain ethyl oxalate, a chemical that can leave harmful residues.’

@abbeyskitchen keeps it simple: ‘Is your dishwasher ruining your GUT HEALTH?!’

These are just some of the TikTok videos with millions of views that claim the residue left on plates by dishwasher tablets and rinse aid could trigger inflammation, food intolerances and even autoimmune conditions.

The suggestion is that the residue contains chemicals that damage the body’s protective gut lining – and the influencers behind them insist the scare is backed by science.

It has caused what many parents thought impossible – teenagers so worried that they are avoiding dishwashers altogether, choosing to scrub their crockery by hand instead.

The alarm was sparked by a 2023 study in the Journal of Allergy and Clinical Immunology, which suggested that chemicals in dishwasher rinse aid can damage cells lining the stomach, leaving tiny gaps that may let toxins and bacteria ‘leak’ into the body.

As Cezmi Akdis, a professor of immunology at the University of Zurich, who led the study, told the Daily Mail, the damage is caused by alcohol ethoxylates in rinse aid – a chemical that makes water run off dishes and glasses, so you don’t get spots or streaks.

‘It is the shining material remaining on the glasses, plates and cutlery,’ he says.

In the lab-based study, ‘we showed that alcohol ethoxylates are toxic to human gut epithelial cells [cells lining the gut]. The data on the rinse aid is quite convincing,’ he argues, adding the chemicals can be toxic to gut cells even when diluted tens of thousands of times.

Yet in everyday products it is present at much higher levels, up to 10 per cent in detergents and 5 to 10 per cent in liquid soaps, says Professor Akdis.

The concern is that something cleaned in the dishwasher would be used to eat/drink from, and any residue chemicals would be consumed.

Professor Akdis says the chemicals could cause a build-up of harmful molecules in the body that prevent cell DNA repair and even force cells in the gut to self-destruct.

As a result, this could lead to problems such as asthma, eczema, psoriasis, food allergies and irritable bowel syndrome, he told the Daily Mail.

Gut barrier damage has also been linked to autoimmune conditions such as Hashimoto’s thyroiditis, which causes an underactive thyroid.

However, Professor Akdis also explains that the risk depends heavily on the type of dishwasher machine.

Commercial dishwashers blast plates clean in just a minute and dry rinse aid straight on to the surface, with no way to adjust the cycle.

Household dishwashers, by contrast, run for around an hour, use more water: consumers also have other options – ‘Rinse again with water, use detergents without rinse aid, use vinegar instead of rinse aid.’

If substituting vinegar, people typically place a small cup of white vinegar up-right on the top rack for the final rinse or add a small amount to the rinse-aid compartment. (Note some manufacturers caution that frequent vinegar use may degrade rubber seals.)

‘For professional devices, the risk is higher because the process cannot be modified,’ says Professor Akdis.

TikTok videos have also seized on studies about microplastics, claiming that tiny particles of plastic stay on plates after a wash.

In fact, research has measured plastics in the wastewater produced by dishwashers, not residues left on crockery – and these come from the plastic utensils etc that are being washed.

A 2023 Spanish study in the Journal of Environmental Science and Pollution Research found that dishwashing cycles – particularly hot, intensive ones – released over 1,000 microplastic particles per load into wastewater. Most came from plastic items being washed or the dishwasher’s own plastic components.

In May 2025 a team in Australia reported even higher figures, estimating that a single load of plastic items could shed up to 920,000 micro- and even smaller nano-particles into wastewater. But, as with the 2023 Spanish study, this group did not measure whether any of these particles remained on crockery.

In fact, their estimate of the total mass of plastic released was minuscule – less than six milligrams per person per year, or about a quarter the weight of a grain of rice.

‘Despite the high number of particles released, the total mass is low and minor compared to other known sources such as laundry,’ lead researcher Dr Elvis Okoffo told the Daily Mail.

Amanda Laca Pérez, a professor of chemical and environmental engineering at the University of Oviedo in Spain, who led the 2023 study, added that their findings should not be interpreted as a reason to stop using dishwashers.

She recommended washing scratched or older plastic containers on cooler cycles to minimise the release of plastic particles.

Another concern raised online is that the plastic-like film that wraps dishwasher pods can cling on to dishes.

This film is made from polyvinyl alcohol (PVA), a water-soluble synthetic compound. However, a 2021 study in the International Journal of Environmental Research and Public Health suggested that most of the soluble film dissolves and is flushed away, with no evidence it remains on plates in amounts that could affect health.

The issue is environmental, not a health one, says Dr Charles Rolsky, a senior re-search scientist at the Shaw Institute in the US, who led the 2021 research.

‘There is no evidence PVA leaves harmful residues on plates or damages the gut,’ he says, but argues that more testing is needed to track where it ends up.

So the real risks lie in industrial kitchens, not the family home, and with a few simple tweaks – such as using gentler products or rinsing again – you can load the dishwasher without fear.

But experts say it’s still better to use a dishwasher to get plates clean and avoid harmful bacteria.

‘Dishwashers get kitchen items hygienically clean through heat disinfection – we can’t do that by hand washing as we would burn ourselves at the temperature needed to kill germs,’ says Dr Lisa Ackerley, a food safety expert from the Public Health Company.

‘Utensils used in preparation of raw meat, poultry, fish and root vegetables – such as cutting boards and knives – in particular need to be disinfected to kill bacteria such as campylobacter or salmonella, which could be harmful if left on surfaces and transferred to ready-to-eat foods.

‘This can be achieved with chemicals or heat. The dishwasher can take away un-certainty, which is why I use one – as well as for the convenience.’