Understanding gut health
Ever been told to trust your gut? The expression turns out to be true. We have a second brain and it happens to be right in our bellies.
Since about a year, I have been obsessing over gut health and the impact it has on our overall health. More and more studies show that our intestinal tract may play a role in a variety of diseases that we thought had nothing to do with our bellies. I’m talking about conditions like depression and anxiety, insomnia, Parkinson’s, Alzheimer’s, autism, acne, eczema, psoriasis, allergies, diabetes, heart disease… the list is long.
First, let’s have a look at how intestines are built. We are taught in school that we have two intestines: the small and the large. Anatomically speaking, it’s true, but from a functional perspective, we have more because every section is specialised in absorbing a certain type of nutrients. Nonetheless, their structure is roughly the same everywhere. To keep things simple, imagine a tube made of several layers of muscle, connective tissue and a lot of folds towards the center. The most central layer is called the epithelium and it’s directly responsible for absorbing nutrients from the lumen and transferring them to the layer underneath, where they will be able to reach our bloodstream.
Blood vessels are not the only thing you find in our intestine walls. We also have a lot of neurons in there. About two to six hundred million autonomous neurons, which is equivalent to the brain of a cat or a dog. For a long time, we believed they were only there to make our intestinal tract move and that the information only went from our brain to our gut and never the other way around. It turns out gut neurons do way more than that. They communicate with our gut, but with our brain too, and believe it or not, they are affected by what we eat. We still know very little, but for example, it’s estimated that the neurons in our intestines are responsible for the secretion of over 90% of our serotonin… which happens to be the neurotransmitter people with depression are lacking.
Mind blown yet?
It gets even better! We each have our very own ecosystem living inside of us. From the moment we are born, we have trillions of micro-organisms colonising our intestines from the food we eat. In fact, we are made of 10 times more bacterial cells than human cells (this is possible because they are much smaller in size than our cells, but that’s another story). In a way, we are more bacteria than human… but also a little bit virus and a little bit fungi. Some are useful and friendly, others not so much. It’s all about balance in there. They thrive on what we eat and their job is to help us break down our food into beneficial compounds we absorb in exchange for shelter. But sometimes, things go wrong and one of the bad species takes over. It can be because we took antibiotics or another type of medication, stress or because our diet is not so great. This can lead to local symptoms like bloating or constipation, but also more subtle signs like chronic inflammation and leaky gut syndrome that will have an impact on our entire body either because of unwanted compounds entering our bloodstream or because those compounds affect the gut neurons.
Scientists have compared the microbiome of people who eat a standard western diet with the microbiome found in populations who eat what’s considered a more primitive diet and the results showed that there is a loss in bioversity of around 30%. While this alone doesn’t make people sick, it increases the odds of developing an imbalance simply because the bad guys have less competition. Poor gut flora was put in evidence in people who suffer from chronic diseases like obesity, heart disease and type 2 diabetes as opposed to people with healthier guts who have a better overall health.
So how do you improve your gut health?
I’m sure you’re thinking about probiotic capsules, right? Well, it turns out they are only useful in certain diseases or after a treatment with antibiotics. A healthy microbiome is a rich microbiome and the best way to achieve that is through what we eat. The secret lies in plants. and there are three things you need to do. First of all, you gotta eat your greens. Whole food plant based diets are rich in prebiotic fibers that promote the growth of friendly bacteria. So the best way to take care of your microbiome is to eat fruits, vegetables, grains and legumes and also include loads of different spices into your meals. The more variety, the better. The second thing you have to do is to include fermented foods like kefir, sauerkraut or kimchi in your diet. Traditionally, fermented foods were a way to preserve food but today, we lack them terribly because we have access to fresh food at all times. They are extremely beneficial because they are natural probiotics and will increase good bacteria counts. On the contrary, refined sugar, animal products and excess alcohol seem to be detrimental as they promote the growth of the bad type of bacteria. And finally because our brain is connected to our gut, things like sleep, exercise and stress will also affect our gut health, so try to take care of those too. Oh and… DO NOT ever get a colonic. Ever!