"Just go with your gut feeling." This common phrase is said all the time. It urges us to trust our instincts and intuition, based on the notion that our gut is capable of feeling. If you've ever stopped to think about the saying and its meaning, it may seem odd. But it's almost guaranteed that at some point in your life, you've had a gut feeling that you couldn't explain, that turned out to be right. So, what's going on here?

According to Dr. Emeran Mayer, a gastroenterologist, neuroscientist, and the author of The Mind-Gut Connection, the whole notion of gut feelings makes perfect sense and is easily explained by over forty years of research. He explains in an article on Goop that tiny microbes in our gut do indeed communicate with our brain, with the two being closely intertwined. Whatever is going on in our gut influences our brains and whatever is going on in our brain is mirrored in our gut.

This makes sense. Ever feel butterflies in your stomach because you're excited or nervous? Or your stomach feels like it's in knots when you're stressed or angry?

Mayer's work examines the impact of what we eat and how it can affect our mood, our immunity, our mind-set. The gut communicates with our brain through several channels: the immune system, the endocrine system, and the nervous system. If your gut is inflamed from a high-fat meal, you may feel tired, unwell or in a bad mood. If you've eaten a healthy meal, you're likely to feel good with an enhanced mood.

You may have heard that our gut is our second brain, but Mayer believes it's actually our first brain. The enteric nervous system is the collection of nerves found in our gut, and it developed a long time before the human brain did (think hundreds of millions of years). Most of the molecules in the brain are derived from that system.

According to Mayer, the gut microbiome influences our social and emotional behaviors and even brain health. His research has and is studying the relationship between the gut microbiome and brain disorders including Alzheimer’s, Parkinson’s, depression, anxiety, and autism spectrum disorders.

Picture the brain and the gut as a circular system, with harmonious communication the goal. When systems are out of balance, there are targeted therapy approaches that can help restore balance, such as stress management and a plant-based diet. Plant-based diets, as you may guess, consist of foods mainly derived from plants, such as vegetables, grains, nuts, seeds, legumes and fruits. Modest or low amounts of animal products are consumed.

If you're interested in learning more, read the original article, which covers this topic in much more detail.