The Gut Microbiome

1 Jul

Everything comes down to....

There is more and more evidence arising about how our gut bacteria not only is hugely influenced by what we eat, but more importantly - that our gut bacteria may be having huge influences on how we feel. Yes, that's right, whether we are happy, sad, anxious, depressed or otherwise 'not quite right'.

"Micro-organisms in our gut secrete a profound number of chemicals, and researchers... have found that among those chemicals are the same substances used by our neurons to communicate and regulate mood, like dopamine, serotonin and gamma-aminobutyric acid (GABA)." (Link)

There is also now a suggestion that the type of bacteria in our gut - can impact our weight - that different bacteria will help process food in different ways affecting the calorie component we eventually receive.

New evidence indicates that gut bacteria alter the way we store fat, how we balance levels of glucose in the blood, and how we respond to hormones that make us feel hungry or full. The wrong mix of microbes, it seems, can help set the stage for obesity and diabetes from the moment of birth. (How Gut Bacteria Help Make Us Fat and Think)

What is our gut?

Our gut (stomach, intestines but especially our large bowels) are full of micro-bacteria. In fact, it is suggested we can hold up to 2kg worth of gut bacteria. It lives in a fine balance of appropriate levels of so-called 'good' and 'bad' bacteria and where it resides is important - too much bacteria in the small intestine leads to SIBO (small intestinal bacterial overgrowth) and is known to cause bloating, gas, abdominal discomfort and food reactivity. It serves an amazing range of functions: from helping to synthesise and produce vitamins, helping to digest certain foods and most importantly it helps to support our immune function. While in utero we have very little bacteria, we begin accumulating bacteria the moment we are born - and if we are lucky - born vaginally. This initial coating of vaginal biota can impact our health for many years to come.

(The impact of our gut bacteria is best explained in the video by Scrubs - "Everything comes down to poo...." (Go and take a look now - it's worth a watch). And it seems that science is backing this little ditty up more and more.)

You transplant what??

The weirdest thing that has evolved from the discovery of the importance of our microbiome is faecal implants. Yep, you guessed correctly - transferring poop from one being to another. It not only helps treat all sorts of gut complaints, in animal studies, it also can change the behaviour in mice or monkeys. Ie the formally anxious mouse, becomes less anxious when implanted with a chilled-out mouse’s gut bacteria (from its poop). Faecal transplants have been used in humans also - mostly to treat symptoms of chronic diarrhoea (such as the bacteria clostridium diff.) and other bowel disorders (such as irritable bowel syndrome and colitis) but some transplants have been shown to improve the behaviour of autistic children with good results. (An example of that here.) There are more studies needed on autism as the results are mixed, but some research suggests autism may be related to disordered gut bacteria.

Unfortunately, we are not yet up to the point of being able to 'prescribe' a certain type of bacteria for treating mood symptoms, but there have been some promising studies (once again - mostly on animals) in treating some behaviours (such as anxiety) with specific microbacteria.

There is something we can do to ensure that our gut bacteria is up to scratch so to speak... and that has to do with what we eat.

Supporting our microbiome

To improve our gut bacteria - we need to consume 'pre-biotic' foods. These are the food that probiotic (bacteria) love to feed on. This includes high-fibre fruits and vegetables, and foods that contain inulin such as onions, leeks, garlic, oats and bananas. The more fibre the better - think kale, celery, broccoli (eg the salks of the broccoli). Polyphenols - the colours in fruits (such as berries), vegetables and some spices (eg turmeric) also seem to do wonders for our gut and immune system.

Ideally - we should also be consuming probiotic-containing foods. These are naturally fermented foods and include yogurt, naturally fermented vegetables such as Korean kimchi, sauerkraut, natural miso and pickled vegetables.

What to avoid to support a good gut microbiome

Avoid processed foods and simple carbohydrates which lack fibre, often lack colour and are devoid of nutrients - these are the worst for our microbes.

Antibiotics are one of the most damaging things to both the 'good' as well as the 'bad' bacteria in the gut and should be avoided unless absolutely necessary. In some individuals, it can take up to one year for the gut bacteria to return to its normal state. Unfortunately, hand sanitisers and anti-bacterial soaps and sprays kill all bacteria - good and bad - so are best avoided. (Washing your hands with soap and water does the trick!)

Other advice? Get a pet - they carry a range of bacteria which increase our own (the more variety we have - the better). Play in the dirt - soil is full of bacteria shown to have positive effects on our health - which may be one of the reasons why being in outdoor spaces has been shown to have beneficial effects on our health.

It only takes a few days of a change in diet to change the micro-bacteria in our gut - a few days for example of high sugar, low fibre eating can produce major changes in our gut microbes (for the worse) so any improvement you can make to support your microbiome is going to help you keep your gut healthy and may even help you feel mentally better :)

(For some fascinating research on this topic, check out the Human Food Project. The lengths people go to!)