"Man is what he eats," wrote German philosopher and anthropologist Ludwig Feuerbach in 1850 in one of the many writings he did titled 'Teachings of Nutrition.' And he was quite right... we all know that ultra-processed foods are harmful to the body, as several articles published this Tuesday in 'Brain Medicine' confirm. Microplastics from ultra-processed foods could be accumulating in human brains and potentially contributing to the global increase in rates of depression, dementia, and other mental health disorders, reports Servimedia.
These writings offer the most comprehensive analysis to date of how tiny plastic particles could affect brain health through multiple interconnected biological pathways.
This month's cover of the magazine shows a human brain speckled with colorful microplastic particles (less than five millimeters) next to a plastic spoon, reflecting that human brains contain approximately 'a spoonful' of microplastic material.
An opinion article by Nicholas Fabiano from the University of Ottawa (Canada); Brandon Luu from the University of Toronto (Canada); David Puder from the Loma Linda University School of Medicine (United States), and Wolfgang Marx from the Food & Mood Center at Deakin University (Australia), provides emerging evidence to propose a novel hypothesis connecting the consumption of ultra-processed foods, exposure to microplastics, and mental health outcomes.
"We are seeing converging evidence that should concern us all," explains Fabiano, who adds, "Ultra-processed foods now account for over 50% of energy intake in countries like the United States, and these foods contain significantly higher levels of microplastics than whole foods. Recent findings show that these particles can cross the blood-brain barrier and accumulate in alarming amounts."
Researchers link the consumption of ultra-processed foods to adverse mental health outcomes. A recent review published in 'The BMJ' found that people who consumed ultra-processed foods had a 22% higher risk of depression, a 48% higher risk of anxiety, and a 41% higher risk of sleep problems.
Researchers point out data showing that foods like chicken nuggets contain 30 times more microplastics per gram than chicken breasts, highlighting the impact of industrial processing.
This hypothesis gains further credibility with recent findings published in 'Nature Medicine' that demonstrated concentrations of microplastics in the human brain ("equivalent to a spoonful," according to researchers) with levels three to five times higher in those with documented dementia diagnoses.
"This hypothesis is particularly compelling because we see a notable overlap in biological mechanisms. Ultra-processed foods have been linked to adverse mental health through inflammation, oxidative stress, epigenetics, mitochondrial dysfunction, and alterations in neurotransmitter systems. Microplastics appear to operate through similarly notable pathways," Marx indicates.
On the other hand, an article examines preliminary evidence that extracorporeal therapeutic apheresis (a technique that filters blood outside the body) could have the potential to remove microplastic particles from human circulation.
"While we need to reduce our exposure to microplastics through better food choices and packaging alternatives, we also need research on how to eliminate these particles from the human body," notes Stefan Bornstein, the study's author, who adds, "Our initial findings suggest that apheresis could offer a possible way to remove microplastics, although much more research is needed."
The topic is contextualized with an editorial by Ma-Li Wong titled 'The Calamity of a Plastic Spoon in Your Brain,' framing the collection of articles not only as a scientific warning but as a paradigm shift in how environmental contaminants and brain health should be considered.
"What emerges from this work is not a warning. It is a reckoning," writes Wong, who emphasizes, "The boundary between the internal and external has failed. If microplastics cross the blood-brain barrier, what else do we believe remains sacred?"
The authors of the four articles emphasize that their analyses add another dimension to the growing argument to reduce the consumption of ultra-processed foods and develop better methods to detect and potentially eliminate microplastics from the human body.
"As levels of ultra-processed foods, microplastics, and adverse mental health outcomes increase simultaneously, it is imperative that we further investigate this possible association," Fabiano stresses, concluding, "After all, we are what we eat."