According to Greek physician Hippocrates, “All disease begins in the gut”, yet it’s taken 2,000 years for modern science to wake up to its importance. In fact, current research is uncovering links between the state of our intestines and almost all other aspects of our health: the influence of our gut over how we think and feel is so extensive, some scientists call it the ‘second brain’.
The gut ‘microbiome’ is the collective word for the trillions of microscopic organisms within the small and large intestines of the human gastrointestinal tract (GIT), mainly bacteria and fungi. We have a very close association with these microbiota. Some 70-80% of our immune system is located in our gut; bacteria forms a physical barrier that covers the gut wall, helping to prevent viruses and other illness-causing microbes from entering the body. More than that, this bacteria also stimulates the lymph system that lives within the gut wall to produce lymphocytes (the white blood cells that fight infections) - just one of the reasons they are key for our health and the prevention of chronic disease.
“A healthy balance of bacteria may help to better manage inflammation in the body,” says nutritional therapist Eve Kalinik. “Current research suggests a link between the state of the microbiome and inflammatory disorders such as diabetes and heart disease, as well as autoimmune conditions such as rheumatoid arthritis. I believe the current interest in gut health has been forced on us by an exponential rise in these complaints.”
But it’s not just inflammatory and autoimmune disorders that our microbiome influences. Recent studies have shown that, alongside our genes, out-of-whack gut microbiota can also contribute to colorectal cancer (bowel cancer). “Colorectal cancer is a huge burden in the UK, and is mostly preventable,” says Dr Lisa Das, consultant gastroenterologist at OneWelbeck clinic in Marylebone. “There is a genetic role in the development of colorectal cancer, and I believe a dysbiotic microbiome [the scientific term for microbial imbalance] also plays a role. Specifically what and how to manage or alter this, however, is still under investigation.”
Mental health is also increasingly in the picture. Not only is some 90% of the ‘happy hormone’ serotonin manufactured in the gut, but an overgrowth of unfriendly bacteria, such as Klebsiella, may release chemicals that prevent our brain from using the serotonin we have already made. “In the same way that when we feel stressed in our mind, it affects our gut,” says GP and Doctor in the House presenter Dr Rangan Chatterjee. “We are also discovering that when our gut is unhappy it can send messages to our brain, via the vagus nerve. It is a two-way conversation.” The research around how the gut-brain dialogue works is still in early stages, but specialists are exploring the hypothesis that an imbalance in bacteria could actually lead to anxiety and depression.
But how can you tell if your gut is in a bad place? “Obvious issues are gas and irregular bowel movements,” says Kalinik. “But things like low mood, disturbed concentration, dull skin, food cravings, poor immunity and low energy could be other things to look out for.” Many of us may, she says, have become so used to living with the more minor complaints such as bloating, we don’t realise these can be fixed. Or, for that matter, that they may be symptoms of a greater problem.
Clearly, we should be taking better care of our microbiome. The good news is that small lifestyle changes can make a tremendous difference to the gut - and, in turn, to the rest of our wellbeing. “We need to become more respectful of the process of eating,” advises nutritional therapist Peter Cox, emphasising the value of sitting down to eat and chewing food well. “We need to avoid processed foods and sugar, or excessive coffee and alcohol, and look to diversify our diets. Most of us struggle to eat a wide range of foods. Aim for seven vegetables a day, including leafy greens like kale and spinach, bitter herbs such as endive, radicchio and rocket (which are nutrient-dense, and stimulate the liver to produce digestive bile).”
Foods containing non-digestible natural fibre - aka prebiotics - have a particular benefit, as the fibre stimulates the growth of beneficial bacterial. Such foods include leeks, garlic and onions, plus oats. Fermented foods such as sauerkraut, kimchi and natural ‘live’ yoghurts are also ideal. And what about probiotics - products that actually contain strains of beneficial bacteria? Take them, but do your research - many probiotics fail to deliver their bacterial load to the gut as too often they are killed by the digestive process. One that has been proven by a recent study, undertaken by Professor Simon Gaisford at University College London, to deliver bacteria to the gut alive and thriving is Symprove, a water-like drink in which four bacteria are suspended (£79 for four weeks; symprove.com). Symprove has consistently impressive clinical trials when used for IBS and IBD - and also in patients with recurring infections such as e.Coli.
“When you have an effective probiotic,” explains Gaisford, “the new bacteria that reaches the gut can lower the resting pH of the gut to a point where pathogens - such as e.Coli or MRSA - cannot survive.” According to a study Gaisford published last year in the International Journal of Pharmaceutics, probiotics can also raise the levels of butyrate - a fantastically health-promoting short-chain fatty acid, which is critical in reducing inflammation (with knock-on benefits to almost all aspects of wellbeing). “This basically means that taking an effective probiotic can make a healthy person healthier.”
Sadly, though, supplements are not a silver bullet. Lifestyle will also have a significant impact - in particular whether you exercise enough, get sufficient sleep and take time to relax. “One of the most important ways to manage gut bacteria is managing stress, so consider meditation,” says Kalinik. Also, ditch the midnight munchies. “Eating late is asking your gut to work late. Fasting overnight for 12 hours, so having nothing later than 8pm or earlier than 8am, seems to have a positive effect on the microbiome, giving your body proper time to rest and digest.”
For some of us, more radical action may be needed. In such cases, Cox and Kalinik both use stool analysis. These cost from around £270 and can give a comprehensive snapshot of issues such as yeast overgrowth and parasites, which can then receive targeted treatment. They both caution against cheaper home-testing, as the value of the test lies in the expert interpretation. So for those wanting to collect samples in the privacy of their own home, opt for a test that allows you to send samples off for professional analysis.
For individuals with really severe conditions, for example when a bacterium called Clostridium difficile (C. difficile) dominates the bowels, resulting in life-threatening extreme diarrhoea, tummy cramps, fever and infection, a faecal microbiota transplant (FMT) can be undertaken. This involves a healthy person’s stool being implanted into the colon of someone who is unwell, the idea being to improve their microbiome.
Already used at Guy’s and St Thomas’s for C. difficile, private clinics are also introducing FMT, with research showing it can improve IBS and ulcerative colitis symptoms, encourage weight loss and decrease depression, among other things. One such clinic is the Taymount Clinic in Hitchin, the first specialised clinic in the world, with over 2,500 clients completing a ten-day Gut Flora Transplant programme to-date. A pioneer in digestive health, the clinic only transplants microbial cells and uses ten donors per client to increase microbial diversity.
But if you feel your gut is out of whack, start by making those food and lifestyle tweaks, which are often enough, according to Chatterjee. So next time you’re out for dinner and you see kimchi on the menu, remember: go with your gut.
Original article published in Allbright Magazine, in January, 2020