Did you know for example, that recent estimates for the number of brain cells in the gut is around 500 million?
So, when people say they’ve got a ‘gut feeling’ about something, they’re undoubtedly right. The ‘butterflies’ we experience before the interview are real, and a measure of our digestive tract’s intelligence.
Did you know that the gastrointestinal system can operate wholly independently of both the brain and the spinal column?
Of course, you already knew that you didn’t have to be consciously aware of digestion, much like you don’t have to be aware to carry on breathing. But, unlike breathing which stops if the connection with the brain is terminated, digestion carries on regardless.
So, what is 500 million neurons anyway? Is it a lot or a little? What can I compare it with?
Well a good thing to compare it with is the size of an animal’s brain.
Neuroscientists estimate that rats brains have around 50-100 million neurons. And rats can be trained to do quite a lot. So, you’ve got a ‘brain’ in your digestive region that has the processing power of 5 rats.
An octopus’ brain has around 300 million neurons.
Clearly this is an exact science, with no doubt every single neuron counted individually in each captured octopus.
But the illustration serves a point.
Your gut has intelligence. A not insignificant intelligence, that has capacities far greater than most of us are aware.
What if our gut can be trained, in the same way as we might train a lab rat?
What if our digestive system has already trained us to choose the foods that it wants, due to the large amounts of serotonin and dopamine it receives when certain foods are digested?
Did you know that 90% of the serotonin in our body is located in the digestive system at any one time?
Serotonin is generally believed to be a key factor in determining people’s happiness and well being.
This study concluded that around half of the dopamine produced in the entire body is produced by the mesenteric organs (digestive tract, pancreas, spleen). Here’s a brief extract from the Wikipedia entry on dopamine:
Every type of reward that has been studied increases the level of dopamine in the brain, and a variety of addictive drugs, including stimulants such as cocaine, amphetamine, and methamphetamine, act by amplifying the effects of dopamine.
So, it certainly suggests that there could be a bit more to digestion than just getting energy and nutrients into the body.
Well, not only that. What if the connection between our gut and our feelings was just a bit more complicated than we thought?
It suggests that any talk of the macronutrients fat, carbohydrate and protein, is a gross over-simplification of the real contents of food. It explains that it is potentially far more helpful to consider food as a collection of molecules that can send signals to the body, rather than purely as macronutrients.
So not only is the body creating hormones in response to what it’s digesting, but there are hormones in the food itself that are directly signalling to the body’s systems.
Perhaps causing it to feel good, and then setting up a chemical dependency on a particular type of food.
Now, is that so far fetched? I mean, that’s exactly how drugs work! So the body is certainly susceptible to this. Why isn’t food thought of as a drug? Especially as it can have a direct effect on around 500 million neurons, and can also directly influence where 90% of the body’s ‘feel-good’ hormone, serotonin, originates.
Did you know that of all the DNA in your body, only 1% of it is human?
That may take a bit of time to sink in…
According to the most recent research in the field, 99% of the DNA in your body is from microbes, bacteria, etc. living inside your body, most of it being in the digestive tract.
Some scientists are now suggesting that the human body should be thought of as a super-organism with trillions of organisms working symbiotically rather than an isolated single being. In 2008, scientists recorded up to six different tribes of bacteria living on our inner elbows? It turns out that these bacteria process the raw fats the skin produces and in turn moisturize your skin.
There are approximately 10 trillion human cells in our bodies, and around ten times this number of bacterial, fungal and other cells. That’s around 100 trillion tiny, fully-functioning organisms on and inside every single one of us right now, as we go about our business.
‘You know what? We don’t really know that much about any of this stuff. Let’s just keep exploring, keep trying stuff and perhaps rely on the body’s intelligence to work this stuff out for itself. And by that I mean we should probably stay as close as possible to things that have worked for millions of years.’