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Microplastics: What You Can Actually Reduce

The one change with randomized evidence behind it, the famous credit-card figure explained, and an honest read of what regulators do and do not know.

Mixed: one 7-day pilot randomized trial with a surrogate endpoint, and no support at all for the supplement claim
In-house · synthesized from the cited primary sources
At a glance
Time
8 min
Difficulty
Beginner
Moderate The strongest evidence here is a 7-day randomized pilot in 60 adults, and it measured plastic-associated CHEMICALS in urine, not plastic particles.
What the evidence says

Change the packaging your food arrives in first

A 7-day pilot randomized controlled trial in 60 adults across five arms, alongside a 211-participant observational cohort, tested a low-plastic diet. Results: mono-n-butyl phthalate down 37.5% (95% CI -55.6 to -12.0, P=0.007); monobenzyl phthalate down 53.5% (95% CI -72.7 to -20.6, P=0.005); bisphenol A down 59.7% (95% CI -82.5 to -6.87, P=0.033). The food arm produced the broadest effect.
Why ↓

This is the strongest thing on the page and the only randomized test of a change you can make. EVIDENCE TIER B: randomized and controlled, but a 7-day pilot in 60 people using a surrogate endpoint. DISCLOSURE: funded by a Minderoo Foundation grant to the University of Western Australia. CRITICAL WORDING: this measured plastic-associated CHEMICALS in urine, NOT plastic particles. Nobody has shown a diet change lowers the plastic particle burden in a human body.

PERTH Trial, Nature Medicine, 2026;32(5):1871-1883, registration ACTRN12622001252707 (PMID 42014506)

Notice when chemicals become particles in a sentence

The trial measured urinary phthalate metabolites and bisphenols. It did not count microplastic particles in blood, tissue or stool. "Cut your microplastics by 60%" is a different claim from the one the data supports.
Why ↓

This is the single most common error in microplastics coverage and it is worth learning to spot, because it is what makes an honest 7-day pilot sound like a solved problem. EVIDENCE TIER A that the distinction exists; the underlying trial stays TIER B.

PERTH Trial, Nature Medicine, 2026, primary endpoints

Retire the credit-card number

The origin is a 2021 paper that pooled 59 publications and modelled a range of 0.1 to 5 grams per week. The credit card corresponds to the TOP of that modelled range, and was publicised by a campaign group. A 2022 peer-reviewed critique states in its abstract that the estimate overestimates intake by several orders of magnitude, and cites a separate modelled median of 4.1 micrograms per week from Mohamed Nor et al. (2021).
Why ↓

Nobody weighed anyone's plastic intake. Two models of the same literature differ by roughly a millionfold, which tells you how unsettled the measurement is. EVIDENCE TIER A: that the figure is modelled, and that the criticism is peer reviewed, are both documented facts.

Senathirajah et al., J Hazard Mater, 2021;404:124004 (PMID 33130380); Pletz, J Hazard Mater Lett, 2022;3:100071

Hold both halves at once

A prospective observational study followed 257 patients having surgery to clear a carotid artery, with a mean follow-up of 33.7 months. Polyethylene was detected in 58.4% of the removed plaques, and its presence was linked to a higher rate of cardiovascular events (hazard ratio 4.53, 95% CI 2.00 to 10.27).
Why ↓

This is the strongest human signal that plastics in tissue may matter, and it is observational: the people with plastic in their plaques differ from those without in ways nobody randomized. Linked to, never causes. EVIDENCE TIER B.

Marfella et al., N Engl J Med, 2024;390(10):900-910 (PMID 38446676)

Read the full position, not the quotable half

The FDA page (content current as of 24 July 2024) says "current scientific evidence does not demonstrate that the levels of microplastics or nanoplastics detected in foods pose a risk to human health", and in the same document says that "because there are no standardized methods for how to detect, quantify, or characterize microplastics and nanoplastics, many of the scientific studies have used methods of variable, questionable, and/or limited accuracy and specificity". EFSA states it has not completed a risk assessment and cannot conclude on potential health effects, with a full opinion due at the end of 2027.
Why ↓

Quoting only the reassuring half of the FDA position is the error, and so is quoting only the second half. "No demonstrated risk" and "we cannot measure this reliably yet" are both true at the same time. EVIDENCE TIER A: these are documented regulator positions, not findings.

US Food and Drug Administration, Microplastics and Nanoplastics in Foods (content current as of 24 July 2024); European Food Safety Authority

Check what the source document is before you check what it says

The document behind the current viral claim is a preprint, carrying the standard stamp that it has not been certified by peer review. Its human component measured saliva, via a chewing-gum experiment that its own authors describe as a qualitative imaging-based proof of concept rather than a quantitative exposure assessment. Its own limitations section says the findings should be read as oral and binding proof of concept rather than proof of reduced whole-body plastic burden. The document does not state anywhere how many people took part.
Why ↓

We are not naming the product, the company or any author, and we are not calling anyone dishonest. We are pointing out that the document does not claim what the internet says it claims, in its authors' own terms. There is no evidence tier at all for the claim that any supplement reduces whole-body plastic burden in humans, because no such measurement exists.

Unnamed preprint, authors' own methods and limitations sections

Do not read a rat result as a human result

The claim that a chitosan supplement flushes microplastics from people is built from two papers being conflated. One is a crossover study in 10 healthy volunteers with no placebo arm. The other is a rat feeding study whose numbers are widely presented as if they were human.
Why ↓

Neither supports the claim as it circulates. EVIDENCE TIER B at best for the small human crossover, TIER C for the animal work. This is the same pattern our how-to-read-a-health-headline page walks through.

Casella et al., Foods, 2025;14(13):2190 (PMID 40646942); Liu & Shimizu, Sci Rep, 2025 (PMID 40268980), a rat study

Pick one and hold it for seven days

Either buy loose produce instead of pre-packed, or move hot food out of plastic before heating it. One change, seven days, then decide whether it stuck.
Why ↓

The food packaging arm was where the randomized trial produced its broadest effect, and one sustained change beats five you abandon. Aside on heating: the widely shared microwave study used deionised water and 3% acetic acid as food simulants rather than actual food, so treat it as a reason to be sensible rather than as a measured result from a meal.

PERTH Trial, Nature Medicine, 2026; Hussain et al., Environ Sci Technol, 2023;57(26):9782-9792 (PMID 37343248)
The evidence 7
Moderate

The strongest evidence here is a 7-day randomized pilot in 60 adults, and it measured plastic-associated CHEMICALS in urine, not plastic particles.

Microplastics and Nanoplastics in Foods (US Food and Drug Administration) Read US Food and Drug Administration
Low-Plastic Diet and Urinary Levels of Plastic-Associated Phthalates and Bisphenols: the Randomized Controlled PERTH Trial (Nature Medicine, 2026) Read Nature Medicine, 2026;32(5):1871-1883
Microplastics and Nanoplastics in Atheromas and Cardiovascular Events (Marfella et al., N Engl J Med, 2024) Read N Engl J Med, 2024;390(10):900-910
Estimation of the Mass of Microplastics Ingested (Senathirajah et al., J Hazard Mater, 2021) Read J Hazard Mater, 2021;404:124004
Ingested Microplastics: Do Humans Eat One Credit Card per Week? (Pletz, J Hazard Materials Letters, 2022) Read J Hazard Mater Lett, 2022;3:100071
Assessing the Release of Microplastics and Nanoplastics from Plastic Containers Under Microwave Heating (Hussain et al., Environ Sci Technol, 2023) Read Environ Sci Technol, 2023;57(26):9782-9792
Chitosan and Microplastic Excretion: a Small Human Crossover (Casella et al., Foods, 2025) Read Foods, 2025;14(13):2190
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Not medical advice. This page is for education only and is not a substitute for professional medical care. Consult a qualified clinician before changing your health routine.
Editorial disclosure. This protocol is written and fact-checked by the YourProtocol editorial team directly from the primary sources cited below; it is not written or reviewed by any outside expert.

Is this for you
  • Anyone who saw the credit-card figure and wanted to know where it came from
  • Anyone considering a supplement marketed as removing microplastics
  • People who want one change worth making rather than a list of fears
Cautions
  • The randomized evidence here is a 7-day pilot in 60 people using a surrogate endpoint; treat it as a promising direction, not a settled result
  • The artery-plaque finding is observational and shows a link, not a cause
  • This page does not name any product or company and is not a review of any product
  • Educational only, not medical advice
Common questions
Can you actually reduce microplastics in your body?
One randomized trial has tested it. Over seven days, a low-plastic diet cut some plastic-associated chemicals in urine by 37% to 60%, with food packaging the biggest lever. It measured chemicals in urine, not plastic particles, so the honest answer is that you can measurably reduce exposure to plastic-associated chemicals, and nobody has yet shown you can reduce plastic particles already in the body.
Do we really eat a credit card of plastic a week?
That figure is modelled, not measured. It comes from a 2021 paper that pooled 59 publications and modelled a range of 0.1 to 5 grams a week; the credit card is the top of that range. A 2022 peer-reviewed critique says the estimate overstates intake by several orders of magnitude, and cites a separate modelled median of 4.1 micrograms a week.
Are microplastics proven to be harmful?
Not proven, and not cleared either. The FDA says current scientific evidence does not demonstrate a risk at the levels detected in foods, and in the same document says there are no standardized measurement methods. EFSA says it has not completed a risk assessment and cannot conclude on health effects, with an opinion due at the end of 2027. One observational study found polyethylene in 58.4% of removed artery plaques and linked its presence to more cardiovascular events.
Does a supplement remove microplastics from your body?
No published human study has shown a supplement reduces whole-body plastic burden. The document behind the most viral version of that claim is a preprint that has not been peer reviewed, whose human component measured saliva, and whose own limitations section says it should be read as proof of concept rather than proof of reduced whole-body burden.
What is the single most useful change?
Food packaging. In the only randomized trial of this, the food arm produced the broadest reduction in plastic-associated chemicals. Buying loose produce instead of pre-packed is the version of that most people can actually keep up.
Should I stop microwaving food in plastic?
It is a reasonable habit to change, but it is not the headline action. The widely shared study behind that advice heated deionised water and 3% acetic acid as test simulants, not food. The food-packaging change is the one with randomized evidence behind it.
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