BY UMA NAIDOO
The food you eat can have just as profound an effect on your brain and your mental health as the drugs prescribed by your doctor. The reason: Your gut and your brain are in constant communication with each other.
I once had a patient who was confused as to why I talked about her gut while treating her mind. To her, it seemed irrelevant. “After all,” she said, “it’s not like they are actually next to each other.”
While your gut and brain are housed in different parts of your body, they are physically connected.
The vagus nerve, also known as the “wanderer nerve,” originates in the brain stem and travels all the way to the gut, connecting the gut to the central nervous system. When it reaches the gut, it untangles itself to form little threads that wrap the entire gut in an unruly covering that looks like an intricately knitted sweater.
Because the vagus nerve penetrates the gut wall, it plays an essential role in the digestion of food, but its key function is to ensure that nerve signals and body chemicals can travel back and forth between the gut and the brain, carrying vital information between them, and making the brain and gut lifelong partners.
The Gut-Brain Romance
The basis of all body communications is chemical. In the brain, these chemicals originate from the primary parts of your nervous system (with an assist from your endocrine system): the central nervous system, which comprises the brain and spinal cord; the autonomic nervous system (ANS), which comprises the sympathetic and parasympathetic systems; and the hypothalamic-pituitary-adrenal axis (HPA axis), which comprises the hypothalamus, pituitary gland, and adrenal gland.
The central nervous system produces chemicals such as dopamine, serotonin, and acetylcholine that are critical for regulating mood and processing thought and emotion. Serotonin, a key chemical deficient in the brains of depressed and anxious people, plays a major role in regulating the gut-brain axis. Serotonin is one of the most buzzed-about brain chemicals because of its role in mood and emotion, and more than 90% of serotonin receptors are found in the gut.
In a healthy body, all these brain chemicals ensure that the gut and brain work smoothly together. Of course, as in all delicate systems, things can go wrong. When chemical over- or underproduction disrupts this connection, the gut-brain balance is thrown into disarray. Levels of important chemicals go out of whack. Moods are upset. Concentration is disrupted. Immunity drops. The gut’s protective barrier is compromised, and metabolites and chemicals that should be kept out of the brain reach the brain and wreak havoc.