New research suggests gut microbes may have helped shape the human brain. Primates’ bacteria transplanted into mice changed brain function, learning and metabolism. (Image: Pexels)
The brain as often said to be the centre of intelligence, but new research suggests it may get hidden support from the gut. Scientists have found that the microbes living in the digestive system can shape how the brain develops and functions, hinting that evolution itself may have been partly guided by the trillions of bacteria in the intestines.
The study, conducted at Northwestern University, transplanted gut microbes from primates into mice that had no microbes of their own. Remarkably, the mice’s brains began to resemble those of the species from which the microbes came. Mice given bacteria from large-brained primates, such as humans and squirrel monkeys, showed improved energy production and learning pathways, while those given microbes from smaller-brained primates displayed very different patterns.
“Microbes are acting on traits that are relevant to our understanding of evolution, particularly the evolution of human brains,” explains Dr Katie Amato, lead researcher and associate professor of biological anthropology. “We were able to make the brains of mice look like the brains of the actual primates the microbes came from. It’s incredible evidence that gut bacteria are more than passengers, they’re active players,” Dr Amato tells Moneycontrol.
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The gut-brain connection is revealing itself as far deeper than previously imagined. “It’s fascinating to think that the microbes we carry may be shaping not just the health, but how the brains develop and function,” says Dr Amato.
Here’s how gut microbes shape the brain
Boosting brain energy
Microbes from larger-brained primates increased gene activity linked to energy production, crucial for maintaining demanding brains.
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Improving learning
Synaptic plasticity—the brain’s ability to learn and adapt—was higher in mice with large-brain microbes.
Potential links to mental health
Mice receiving microbes from smaller-brained primates showed gene patterns linked to ADHD, autism, bipolar disorder, and schizophrenia.
Evolutionary influence
These findings suggest gut microbes may have helped humans evolve larger, energy-hungry brains.
Clinical implications
Understanding which microbes support healthy brain development could open new avenues for preventing or treating neurodevelopmental disorders.
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The study builds on earlier work from Amato’s lab showing that gut microbes from larger-brained primates produce more metabolic energy when transferred into mice. This latest research goes further, demonstrating that these microbes can actually rewire brain function, not just supply energy.
Disclaimer: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for specific health diagnosis.