Dr Henry’s güt to know -
Our bodies are pretty spectacular things. From the moment we're born to the second we die, literally trillions (that's one followed by 12 zeros in case you were wondering), of cells are working in perfect unison to allow us to walk, talk, think, love, and do a thousand other things on a daily basis. To top that off, each one of these cells is so small that it cannot be seen with the naked eye, yet it runs more chemical reactions than your average pharmaceuticals lab, and contains enough information in the form of DNA to fill an entire bookcase.
The last fifty years have seen incredible advances in our understanding of how our bodies work at a cellular level; however, one of the most striking discoveries has been how little of "us" is made up of human cells. One of the key components of the human body is the microbiome: the amazing ecosystem of bacteria, fungi, and protists that call our bodies home. Much as we like to avoid 'germs' as much as possible, there is no escaping that fact that we are covered with them, inside and out. The important distinction though, is the difference between microbes that will make us sick, known as pathogenic microorganisms, and those that won't, known as commensal microorganisms. As it happens, there are far more of the latter than the former, in the same way that poisonous plants and man-eating tigers are greatly outnumbered by their friendlier relations. It is these commensal microorganisms that make up a healthy microbiome, although to classify them as simply "not harmful" is to sell them rather short. They are in fact incredibly beneficial to our health, and maintaining the correct balance of these microorganisms has been shown to have huge impacts on a whole spectrum of bodily processes, from the immune system, to metabolism and weight control, and even our mental state.
Just as macro-scale ecosystems (that is to say 'human sized': for example a rainforest) have numerous different environments, the same is true for the human microbiome. Pretty much every inch of your body that has been exposed in any way to the outside world will have microorganisms happily living in it, from your skin, to your mouth, to the inside of your nose (nice!). In every place commensal microorganisms live, they are protecting you from pathogenic bugs simply by being there first and filling up all the space. An area of particular interest is the gut microbiome- here, the commensals not only block pathogens from gaining a foothold, but also interact with our bodies in a vast and complex manner, which we are only just starting to understand. These commensals can conduct complex biochemistry to break down foods we otherwise would not be able to, secrete hormones which regulate various bodily processes, and have also been shown to interact with our nervous system.
In the course of the coming weeks and months I will be exploring the importance of the gut microbiome in much greater detail, bringing you all the latest scientific research on the topic in one easily digestible blog (sorry, couldn't help myself!).