How many brains do you have? The conventional answer is of course "one".
However there are other nervous systems in your body. One network being so extensive it has been coined the 'second brain'. This refers to the enteric nervous system (ENS) and is located mostly in your gut.
While the ENS is much simpler than the brain, it is still immensely complex. In humans it is made up of an estimated 200 to 600 million neurons.
The chemical workshop
Food digestion requires a variety of very precise chemical mixtures produced at the right times and delivered to the right locations. The ENS has this very well executed. The intestinal wall is lined with specialised cells that act as chemical detectors, or taste receptors, identify chemicals present in the food you eat. This data helps the ENS enlist the right digestive enzymes to break the food down into particles that the body can absorb.
Think of your digestive tract as a factory line managed mostly by the ENS. Your "second brain" moves through the digestive system by directing the muscles along the walls of the digestive tract to contract. The ENS varies the strength and frequency of these muscles contractions as needed to make the system function like a
line of conveyor belts.
The ENS is also the chief safety officer. The food you swallow is likely to contain potentially harmful bacteria. It is no wonder that about 70-80 percent of your body's lymphocytes - a vital component of your body's immune system- are housed inside your gut!
If you ingest a harmful organism, the ENS raises the alarms by triggering powerful contractions that expel most of the toxic matter through vomiting and diarrhoea.
Now this is all sounding very mechanistic. But there is more to it than that.
The brain and ENS are in constant communication. The ENS plays a role in regulating the hormones which tell the brain when you should eat and how much.
Another example of communication between the brain and the ENS is described as "butterflies". This feeling may be the result of the ENS diverting blood away from the stomach when the brain experiences tension or stress.
Mindful eating
The next time you think about eating a meal, pause and think about all the monitoring, data processing, coordination and communication that is about to take place in your digestive system.