Everyday there seems be a new study showing the importance of a healthy biome to our overall health and well-being. But what is a biome and how do you keep it healthy?
Your body plays host to a vast array of microbial life including bacteria (helpful and harmful), viruses, moulds and fungi. Collectively they are known as the human microbiota or human microbiome.
That’s the $64 million question and much research is going on around the world to answer it in detail. While these microbes can be found everywhere from our skin, our genitals and our mouths, the ones most “under the microscope” so-to-speak are those found in our digestive system, aka the gut.
The gut microbiome can contain both ‘good’ and ‘bad’ bacteria, yeasts, fungi and moulds. Much research is aimed at determining which microbes are which, what their functions are and what effects they have, not just on the gut, but on the body as a whole.
For example, there are over 100 million neurons in the gut forming what is called the enteric system – a sort of second brain. These neurons “communicate” with the microbiome which can affect your behaviour and feelings including eating habits, cravings and moods. There is also some evidence that making a positive change to the microbiome may reduce anxiety and depression
Most people have heard of Helicobacter pylorii, the bacteria responsible for the formation of ulcers. Others more recently identified are E. coli, Serratia marcescens and Candida tropicalis – a threesome found in higher concentrations in the guts of people with Crohn’s disease. While it’s early stages yet, this discovery holds out the promise of more effective treatments for a disease which is both debilitating and painful.
There is also some ongoing research into the possibility that some members of the Chlostridia family may play a role in disorders such as Autism Spectrum Disorder. Much more research is needed before this is confirmed but it highlights the importance of having a healthy gut microbiome for both your physical and psychological health.
Probiotics are a well-known in the general community. We drink probiotic yoghurt drinks, we eat yoghurt that’s full of Lactobacillis and Bifida bacteria and we pop probiotic capsules in ever-increasing numbers. However, these are just the tip of the probiotic iceberg.
Becoming increasingly popular and mainstream are the fermented probiotics such as kombucha, kefir (water and milk varieties), and fermented vegies such as sauerkraut and kimchi. These contain a variety of bacteria and some, like kefir, contain beneficial yeasts too.
These ‘good guys’ set up a symbiotic relationship with us whereby we feed them and they help us digest our food, produce protective compounds and generally keep us healthy. The take-home message? The greater the variety of bacteria in our guts, the healthier we will be.
So what about pre-biotics?
You’ve probably heard of the term prebiotics. Note the “pre” not the “pro” at the front. These are non-digestible components of food that stimulate the growth of the ‘friendly’ bacteria in the large bowel. The best studied is inulin (fructo-oligo-fructose or FOS), which is a type of carbohydrate that we can’t metabolise. It’s found in chicory root and in lesser amounts in Jerusalem artichokes, onion, leeks, garlic, rye and banana. It acts as ‘food’ for the ‘friendly’ bacteria that happily reside in our large intestine and it activates their growth. They love it. It’s often added to foods as a soluble fibre (think yoghurts, liquid breakfasts etc).
Inulin can often be found added to foods to provide a food source for the probiotic bacteria during storage and is usually just listed as ‘fibre’ on the Ingredient List. Natural prebiotics are found in almost all high-fibre foods but especially in onions, garlic, legumes, asparagus and whole grains, particularly rye.
Another prebiotic is resistant starch and Catherine wrote a post on this on the Foodwatch website which you can read here.
Among the benefits of resistant starch is the fact that it provides a food for the good gut bacteria, the by-products of which are protective of the cells in your gut and can help prevent against colon cancer. The CSIRO has produced a video animation about this called The Hungry Microbiome – well worth a look.
Research from Spain published in Clinical Nutrition studied the effects of inulin and resistant starch in rats. The research indicates that there may be synergistic effects that produce better results than either one shows in on its own.
Three things really.
First we want to limit the amount of bad bacteria we ingest. That means making sure we wash our hand before and after preparing food and eating, and ensuring we follow food safety guidelines. We wrote about this in the July 2017 edition of the Foodwatch Newsletter which you can find here.
Secondly, we want to increase the diversity of the good bacteria in our guts by eating a fibre-rich diet full of the prebiotic foods that the ‘good guys’ love plus we need to introduce probiotic foods into our diet to enrich the gut microbiome. These include yoghurts, kefir, kombucha, kimchi, sauerkraut, miso, tempeh and other fermented foods.
The third thing is to take it slowly. Don’t suddenly go from a low-fibre diet to a high-fibre one overnight. You’ll end up with bloating and stomach pains. Make the change gradually. The same goes for the probiotic foods. Don’t suddenly start consuming vast quantities of them or you could end up with bloating and diarrhoea.
Time to repeat the Foodwatch mantra – moderation, moderation, moderation. If you make changes to your diet slowly you should start to improve the health of your gut microbiome and your overall health without any unpleasant side effects.
Thanks to Munaiba Khan, a retired naturopath with an interest in nutrition.