Microplastics in Poop – The Most Common Removal Method

Microplastics in Poop – The Most Common Removal Method

⚕️ MEDICAL DISCLAIMER: This article is for informational and educational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider before making any changes to your health regimen, diet, or supplement use, especially if you have existing medical conditions or take medications. The information presented here should not be used to diagnose, treat, cure, or prevent any disease.

Our bodies are entirely capable of removing microplastics without intervention. Going “number two” is the most common route for microplastics to leave the body. Numerous studies have found microplastics in poop. While this is positive news, it’s only part of the story. 

The majority of ingested microplastics are removed via feces, especially the larger microplastics. However, smaller fragments, particularly nanoplastics, can pass directly through our intestinal walls, enter the bloodstream, and become stuck in our various organs. This means that, while your body can remove microplastics naturally through going to the bathroom, some of the microplastics stay in our bodies, causing a plethora of problems. 

Microplastics In Poop, The Concerning Findings

Multiple studies have confirmed the presence of microplastics in human feces. These findings have been consistent across geographic regions, dietary patterns, and age groups [1–6]. Fecal samples have tested positive for a range of polymers including polyethylene terephthalate (PET), polycarbonate, polypropylene (PP), and polystyrene (PS) [2,8,15–21]. 

One large case series even documented microplastic contamination in both healthy individuals and patients with inflammatory bowel disease (IBD), suggesting that gut health status doesn’t prevent exposure or excretion [5,12]. Another study in an Indonesian coastal population detected substantial levels of microplastics linked to dietary intake and environmental contact [12,15].

Most, But Not All, Microplastics Are Excreted Naturally

More than 90% of microplastics larger than 150 microns, the diameter of two thin human hairs, are passed through the gastrointestinal tract and expelled in the stool [10]. But, excretion is more nuanced than size alone. Particles smaller than 20 microns, and especially those at the nanoscale, may be absorbed through intestinal villi, lymphatic vessels, or specialized M cells in Peyer’s patches and pass into the bloodstream [5,31]

That means while large microplastics exit, smaller microplastics may remain. Microplastics in poop are mostly “large” ones, greater than 150 microns. 

The structure of the particle matters too. Microplastics shaped as fibers may snag on gut tissue. On the other hand, spherical microplastics may pass more easily through the gut. Surface charge, hydrophobicity, and the chemical composition all influence how the gut is impacted [30,31]. 

Gut Health Influences How Microplastics Are Removed

Factors like bowel regularity, gut permeability, inflammation, and microbiome diversity can all affect the levels of microplastics in poop. A compromised gut barrier, often seen in those with irritable bowel syndrome (IBS), Crohn’s disease, or chronic stress, may allow more particles to slip through and remain in the body [12]. 

Conversely, robust gut motility and an intact epithelial barrier help prevent microplastic absorption and speed up excretion. But even in healthy guts, retention can still occur.

The Toxic Fallout of What Gets Left Behind

Microplastics can damage the gut. Some particles trigger oxidative stress, cytokine release, and apoptosis in gut epithelial cells [3,7,13]. Others disrupt microbiome composition, leading to dysbiosis—a microbial imbalance linked to obesity, depression, and autoimmune conditions [9].

In mouse studies, chronic ingestion of polystyrene nanoplastics led to intestinal barrier breakdown, increased inflammation, and even liver toxicity [3,7,26]. Long-term exposure can also reduce the regenerative capacity of intestinal stem cells, impairing mucosal healing and digestion [9,27].

Stool Analysis as a Diagnostic Window

In the future, it may be more common to use stool as a diagnostic tool for calculating microplastic exposure. Since stool reflects recent exposures, tracking polymer type and particle load could help in several ways, including monitoring exposure sources (like diet and water), evaluating gut permeability, understanding factors that influence clearance rates, and identifying links between microplastic load and disease. Paying for a lab to study the microplastics in poop, your poop specifically, may be a more common practice in the future. This analysis could better inform specific lifestyles, environment factors, and genetics that continue to reduced microplastic exposure. 

How Many Microplastics Are We Actually Ingesting?

The average adult is believed to consume 883 microplastic particles per day from food, water, and air [29]. Over the course of a year, that’s equivalent to ingesting the mass of a credit card—about 5 grams of plastic [20,28]. However, this number varies widely between studies and is generally up for debate. However, some studies, which also account for nanoplastics, suggest that we could be dramatically underestimating the amount of microplastics we eat, drink, and inhale. 

How Can I Lower My Exposure To Microplastics? 

Although some studies have found that most microplastics pass through us, the ones that remain can potentially cause long-term health effects. Consequently, for those of us concerned about our health, it’s important to lower our exposure to microplastics as much as possible. There are many small, simple actions that you can take each day to lower the amount of microplastics you consume. This is why we developed the Deplasto platform. 

Our platform, consisting of a science-backed supplement, a daily microplastic intake app, and lifestyle recommendations is intended to help you avoid microplastics. Our all-natural supplement is formulated to support your body’s natural detoxification defenses, including oxidative stress management, cellular repair, and antioxidant support. Our microplastic intake app is designed to show you an estimate of your daily exposure, with every datapoint backed by scientific studies, to help you understand how you can best avoid microplastics. Lastly, given that it’s nearly impossible to completely avoid microplastic exposure, we have a plethora of lifestyle recommendations designed to help you make small changes for big impacts. 

Overall, we believe that the best way to eliminate microplastics begins with you and the changes you make to your daily life. Over time, collectively, we can make a significant impact on our health and the environment. 

Sources

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