That “gut feeling” that prevents you from taking a job or going on a second date is not some myth. Our stomachs have a way of signaling emotions, are pretty damn clever, and can “think” for themselves. So much so that they may influence neurological diseases. In a bid to understand how interactions between the brain and gut occur, MIT researchers have developed a new “organs-on-a-chip” system that can mimic their interactions.
The brain in your gut
In his 2010 TED Talk, the food scientist Heribert Watzke told a story of how cooking technology brought the human species where we are today. It gave us “the big brain, this wonderful cerebral cortex we have.” He explained that brains are, metabolically speaking, expensive. After all, they use 25 percent of our energy. Since raw food doesn’t release enough nutrients, it was cooking that “made it possible that mutations, natural selections, our environment, could develop us.”
But as Watzke pointed out, the whole story isn’t about one brain: it’s actually about two. Since our gut is interwoven with the emotional limbic system, they can communicate and make decisions hand in hand.
“Now if you think about the gut, the gut is — if you could stretch it — 40 meters long, the length of a tennis court,” Watzke says. On top of that, this second “brain” includes 500 million nerve cells and 100 million neurons, making it the size of a cat brain. That’s why it can “think for itself” when deciding how to digest and process whatever you ate. “It has autonomous organized microcircuits… It senses the food; it knows exactly what to do. It senses it by chemical means and very importantly by mechanical means, because it has to move the food — it has to mix all the various elements which we need for digestion,” Watzke explains. This brain even makes you gag if you encounter food you find disgusting.
MIT researchers embarked on a quest to untangle the connection between the gut and the brain. Their new model uncovered how gut microbes operate with regard to healthy brain tissue and brain tissue of Parkinson’s patients. It turns out that short-chain fatty acids (SCFAs) produced by these microbes have markedly different effects, MIT News reports.
Being exposed to SCFAs is beneficial for healthy brain cells, but not that’s not true for Parkinson’s patients. In their case, the cells experienced higher levels of protein misfolding and cell death. “It seems that short-chain fatty acids can be linked to neurodegenerative diseases by affecting lipid metabolism rather than directly affecting a certain immune cell population. Now the goal for us is to try to understand this,” said the study’s lead author Martin Trapecar, for MIT News.
The mysterious connections
Beyond Parkinson’s, there are likely many more conditions that could be linked to our gut microbiome. We don’t know much yet, and the scientists acknowledge that they need to bring more human tissue models into the research. Unfortunately, animal models could not provide enough information.
Research so far points to everything from anxiety to ADHD and autism spectrum disorders. Besides, microbiome bacteria could even shape our personalities. The famous psychologist Dr. Nicole Le Pera often talks about the gut-brain axis, and she says the future of wellness will inevitably involve the lessons learned about this connection.
We’re still a long way from fully understanding the mechanism that connects our brain, liver, and colon. Looking for a proven holistic wellbeing recipe? That’s not something science can give you signed, sealed, and delivered just yet. But at the very least, science points in one direction. What we’re putting in our system is not only about immunity, digestion, or losing and gaining weight or muscle. We truly are what we eat.