Do Microplastics Make You Fat?

⚕️ 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.

It may seem unbelievable, but there’s evidence to suggest that microplastics can make you fat. After we eat, drink, or breathe them in, microplastics don’t just accumulate in the gut or circulate harmlessly through the bloodstream. Instead, they interfere with metabolism, disrupt hormones, hijack your microbiome, and inflame your liver. Disrupting these bodily functions can lead to weight gain so, in short, microplastics may play a role in contributing to weight gain. 

Here’s how microplastics can impact body fat and metabolic health.

Microplastics Alter the Gut–Weight Axis

The gut microbiome plays a central role in weight regulation. It governs how you absorb nutrients, manage inflammation, and store fat. Microplastics have been shown to disrupt the microbiome, potentially impacting this process. 

Animal studies show that polystyrene, PVC, and polyethylene microplastics disrupt microbiota composition and decrease microbial diversity [1,2,4,13–21]. This leads to gut dysbiosis, which has been linked to insulin resistance, impaired fat metabolism, and increased risk for obesity.

Disrupting the microbiome can also impact the gut-brain axis. Disruption here can alter hunger cues, mood, and neuroinflammation, all of which can influence long-term weight patterns [2,4,13].

Microplastics Cause Fat Storage To Increase, While Slowing Fat Burning

Microplastics affect lipid metabolism at the cellular level. In multiple rodent studies, exposure to polystyrene microplastics led to increased adiposity, more fat tissue overall, and larger fat cells in the liver and subcutaneous tissue [2,5,6,7].

Microplastics also impair lipolysis, the process by which your body breaks down stored fat for energy. In mice fed high-fat diets, polystyrene nanoplastics suppressed fasting-induced lipolysis in white adipose tissue, making it harder to shed weight even with calorie restriction [2,5].

On the flip side, these particles stimulate fatty acid synthesis and promote triglyceride accumulation in liver cells and macrophages, key players in systemic inflammation and obesity [9–14].

Microplastics Disrupt Metabolism Before Birth

Maternal ingestion of nanoplastics during pregnancy has been linked to increased body weight in offspring. This happens through altered placental signaling, shifts in fetal lipid profiles, and microbial transmission at birth [2,8,15].

Microplastics have been detected in the placenta and fetal tissues. Early-life exposure is already being associated with long-term changes in metabolism, suggesting that weight gain from microplastics may start in utero [1,2,18].

Infants are especially vulnerable. Their exposure comes from bottles, pacifiers, and plastic-covered formula—and their immature gut and immune systems offer little defense. Fecal microplastic levels in infants are significantly higher than in adults [2,15].

Microplastic-Induced Oxidative Stress and Inflammation and Create a Vicious Cycle

Inflammation and obesity have a close relationship. Microplastics have been shown to inflamed tissues. They trigger macrophage activation, generate reactive oxygen species, and induce chronic oxidative stress [4,11,22–25]. 

Liver inflammation is a major concern. Studies using liver organoids and rodent models show that polystyrene and polypropylene microplastics disrupt mitochondrial function, promote fibrosis, and impair liver detoxification [11–14,23–24].

This liver dysfunction feeds directly into metabolic disorders like non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD), both of which are rising alongside obesity [28].

Hormones Don’t Stand a Chance

Microplastics can be made of or bind to endocrine-disrupting chemicals, which interfere with nearly every hormone tied to metabolism. Bisphenol A, phthalates, and other additives mimic estrogen, block androgen receptors, and interfere with thyroid hormone production [2,36–38]. 

These disruptions lead to increased adipocyte hypertrophy (fat cell expansion), altered appetite signaling, reduced insulin sensitivity, and changes in fat distribution [2,20,23,26–33].

In men, microplastics have also been linked to testosterone suppression, impaired sperm development, and even early testicular aging, additional endocrine consequences with systemic metabolic effects [6,18,19].

Obesogen Classification and Human Implications

Some scientists have gone as far as declaring that microplastics be classified as obesogens, which are environmental compounds that promote weight gain regardless of caloric intake [1,2,6,13,20,23,26–33]. While human studies are still emerging, early data already show associations between fecal microplastics and markers of metabolic dysfunction [28]. 

Perhaps most strikingly, microplastics have now been found in atherosclerotic plaques excised from human carotid arteries. Patients with microplastics in their arterial walls had a 4.5-fold higher risk of primary cardiovascular events [20,23,34].

These findings reinforce the connection between microplastic exposure, systemic inflammation, and metabolic disease.

How Can I Lower My Exposure To Microplastics? 

There is more and more evidence to support that microplastics and the hormone-disrupting chemicals that they carry can cause long-term health effects. Therefore, the importance of finding ways to lower your exposure, ensure microplastics pass through, and reduce their metabolic byproducts continues to increase. While it’s extremely difficult, if not impossible, to avoid microplastics entirely, 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 microplastic daily intake iOS 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 difference. 

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