Are Microplastics a Hidden Threat to Brain Health? An Expert Weighs In

Environmental exposures are gaining recognition as hidden drivers of chronic disease — and among them, microplastics are emerging as a pollutant of concern.  These tiny plastic particles have become nearly impossible to avoid and are rapidly accumulating in our food, water, and air.  Unfortunately, this also means they are reaching the inside of our bodies — in our blood, organs, and even our brains.¹ 

Microplastics were once considered insignificant.  However, researchers are now uncovering how they may interact with our immune systems, blood vessels, and nervous systems in consequential ways.  One area of growing interest is their potential role in brain aging.  Could these invisible pollutants be contributing to cognitive decline?  We sat down with Thomas Holland, MD, a physician, scientist, and faculty at Rush University Medical Center, and Medical Advisor at NeuroReserve, to explore how microplastics may be silently influencing cognitive aging — and what we can do to protect our brains. 

Q1: What’s the latest in the research around plastics and microplastics and brain health impact?  

Dr. Holland: First, let’s define microplastics.  All plastic eventually breaks down into microplastics and nanoplastics, particles smaller than five millimeters and often much smaller.  These particles are virtually everywhere in our environment, and we are constantly exposed to them.  They originate from the degradation of larger plastic objects like bottles, packaging, and tire wear on roads.  Due to their tiny size, here is the potential that they can enter the bloodstream.  Recent studies have identified microplastics in human brain tissue, showing that these particles can bypass protective barriers.¹  Animal research suggests they can provoke inflammation, oxidative stress, and disrupt neural communication, leading to memory and behavioral changes.²˒³  One study even showed that microplastics carried by immune cells can obstruct small blood vessels in the brain, much like microvascular infarcts, though with a different underlying cause, potentially reducing blood flow and impairing cognitive function.⁴  Altogether, this emerging research gives us valid reasons for concern and underscores the need for further investigation.

Q2: What happens biologically when we ingest microplastics — how do they reach the brain, if at all?  

Dr. Holland:  Microplastics enter the body through the food we eat, the water we drink, and even the air we breathe.  Once inside, these particles can pass through the lining of the gut or lungs and enter the bloodstream.³  From there, smaller plastics, especially nanoplastics, have been shown to cross the blood-brain barrier.⁴  This barrier, made up of specialized cells lining brain blood vessels, protects the brain by filtering harmful substances.⁵  It helps keep the good in and the bad out, playing a crucial role in brain health.  Even more concerning, some research shows that particles have the potential to bypass this barrier altogether by traveling along the olfactory nerve, which connects the nasal passages directly to the brain.⁶  At this point, the question is no longer if plastic reaches the brain, but what it does once it gets there.

Q3: Are concerns about plastic intake and brain function substantiated, or are there myths to debunk?   

Dr. Holland:  One major myth is the belief that plastics are biologically inert, meaning they pass through the body without causing harm.  Although the field is still developing and there is still a lot to learn, what we do know is that microplastics can interact with the immune system, promote brain inflammation, and act as carriers for harmful chemicals or metals into sensitive tissues.³  In fact, the current body of evidence is strong enough to justify preventive action, particularly given concerns around lifelong exposures and their possible role in cognitive decline.

Q4:  From a nutritional standpoint, are there specific foods people should avoid or prioritize to reduce microplastics exposure or aid in detoxification?  

Dr. Holland:  A straightforward way to lower microplastics exposure is to reduce your intake of processed and prepackaged foods, especially those stored or wrapped in plastic.⁷  These items often carry higher contamination levels. In contrast, fresh, unpackaged foods limit plastic contact.  To support the brain’s natural detoxification, prioritize nutrients like omega-3 fatty acids, magnesium, flavonoids (found in colorful fruits and vegetables), and B vitamins.⁸  These compounds can help reduce inflammation, repair cells, and maintain the integrity of the blood-brain barrier.  Dark, leafy greens, berries, fatty fish, nuts, seeds, and fermented foods all help build brain resilience.  Many of these are staples in the MIND diet, which my colleagues and I at Rush University have studied extensively over the past decade.  While it’s nearly impossible to eliminate microplastics completely, we can empower the body’s defenses with thoughtful lifestyle and dietary choices.

Q5: Any practical nutritional or lifestyle tips to help reduce microplastic intake and its potential impact on cognitive health?  

Dr. Holland:  Making a few intentional changes can significantly reduce plastic exposure.  Choose glass, stainless steel, or ceramic containers for storing food and drinks, as plastics can leach harmful substances when exposed to heat, UV light, or friction.⁹  A great place to start is with your water: swap plastic bottles, especially single use bottles, for a stainless-steel thermos, which also keeps drinks hot or cold.  Filtering your drinking water is another helpful step.  As mentioned earlier, opt for whole, unpackaged foods instead of heavily processed or plastic-wrapped items.  These small adjustments can have a meaningful long-term impact.  

Q6: Any final thoughts on microplastics to leave our readers? 

Dr. Holland:   With the advancements we are observing in research, it is clear that we are just beginning to understand the effects of microplastics on brain health, but what we know so far offers a compelling case for concern.  While we can’t eliminate exposure altogether, we can take purposeful steps to minimize it and support our brain’s defenses and enhance our cognitive reserve and cognitive resilience.  The daily choices we make, what we cook, including the cookware we use, how we store our food, and the nutrient dense foods we prioritize, can all contribute to long-term brain health.  It’s never too early or too late to protect your brain, and the earlier we act, the better equipped we’ll be for the future.

Building your diet around brain-protective patterns, such as the Mediterranean and MIND diets, can help reduce inflammation and support detoxification.¹⁰  These diets emphasize antioxidant- and polyphenol-rich foods, healthy fats, and fiber — all of which strengthen your brain’s resilience.  The brain health supplement, RELEVATE, is a great way to fill in nutrient gaps and support long-term cognitive health, especially in a world where environmental toxins like microplastics are increasingly difficult to avoid. 

Learn more about RELEVATE here. 

About Tom Holland: 

Tom Holland, M.D., is a renowned medical doctor and researcher at Rush University Medical Center, and a NeuroReserve Medical Advisor. He has become a trusted authority and invaluable resource for medical advice and insights in preventing Alzheimer’s and cognitive decline. Dr. Holland is regularly interviewed by leading media outlets and popular press for his expertise in brain health and aging. He also serves as Assistant Trial Director, Medical Advisor, and Study Clinician for the national Alzheimer’s Association U.S. POINTER Trial—the first large-scale clinical study in the U.S. aimed at preventing cognitive decline and dementia by simultaneously targeting nutrition, exercise, and other health factors.  Stay connected with Tom Holland by following his instagram here.

References

1. Nihart, A. J. et al. Bioaccumulation of microplastics in decedent human brains. Nat Med 31, 1114–1119 (2025). 

2. Gaspar, L., Bartman, S., Coppotelli, G. & Ross, J. M. Acute Exposure to Microplastics Induced Changes in Behavior and Inflammation in Young and Old Mice. Int J Mol Sci 24, 12308 (2023). 

3. Ali, N. et al. The potential impacts of micro-and-nano plastics on various organ systems in humans. EBioMedicine 99, 104901 (2024). 

4. Huang, H. et al. Microplastics in the bloodstream can induce cerebral thrombosis by causing cell obstruction and lead to neurobehavioral abnormalities. Sci Adv 11, (2025). 

5. Blood-Brain Barrier. Cleveland Clinic (2023). 

6. Amato-Lourenço, L. F. et al. Microplastics in the Olfactory Bulb of the Human Brain. JAMA Netw Open 7, e2440018 (2024). 

7. Yates, J. et al. A toxic relationship: ultra-processed foods & plastics. Global Health 20, 74 (2024). 

8. Gómez-Pinilla, F. Brain foods: the effects of nutrients on brain function. Nat Rev Neurosci 9, 568–578 (2008). 

9. de Paula, L. C. P. & Alves, C. Food packaging and endocrine disruptors. J Pediatr (Rio J) 100, S40–S47 (2024). 

10. van Zonneveld, S. M. et al. An Anti-Inflammatory Diet and Its Potential Benefit for Individuals with Mental Disorders and Neurodegenerative Diseases—A Narrative Review. Nutrients 16, 2646 (2024).