The human gastrointestinal tract houses a huge and complex community of bacteria - collectively known as the gut microbiota. This community of bacteria provides a number of benefits to our health including the regulation of the body's immune system.
Gut bacteria is crucial to health
Science is only starting to figure out just how beneficial the relationship is between our bodies and our gut bacteria but it is already very clear that it has a massive impact on our health, it affects many aspects of human physiology, from metabolism to cardiovascular system, the nervous system and immunity.
The immune system is an army of cells and molecules that protect us from disease by monitoring our body and responding to any foreign invaders they perceive as a threat, particularly infectious microbes. One key player in immune health is the gut - it is the largest immune organ in the body, accounting for 70% of the immune cells in the body.
Poor gut health impairs immunity
There is a continuous conversation happening between our immune system and our gut microbiota from the moment we are born. As we grow our microbiota shapes the development of our immune system, and our immune system shapes the composition of our microbiota. It is a symbiotic relationship. A healthy dialogue within this relationship supports protective responses against pathogens, promotes tolerance to harmless microbes and their products, and maintains the ability of our immune system to not react harmfully to our own body. Imbalances in the gut microbiota may dysregulate and impair our immune responses leading to the development of chronic inflammation and autoimmune issues. This is why it is so important to take good care of our gut health.
Gut microbes get most of their nutrients from our diet and help us digest much of the food we ingest therefore diet has a huge impact on the composition of gut microbiota and, consequently, on our immune system. A healthy microbiome is one that is diverse, containing a lot of different species. This is because each species of bacteria has its own role in immunity and health.
Modern diets, particularly those of the Western world, are characterised by an excessive intake of highly palatable energy-dense foods, including high levels of animal protein, saturated fats, simple sugars and salt, but low amounts of high-fibre plant based foods. This is exactly why western dietary patterns are being increasingly linked to immune dysfunctions.
You need to get the right balance
The right balance between good and bad bacteria within the gut is what we all should be aiming to achieve. We can do a number of things to help address an imbalance and restore health to the microbiota; this includes eating more resistant starch, avoiding sugar, eating more fermented foods and eating organic foods where possible, as these products are free from antibiotics and pesticides.
Taking probiotic supplements is another way you can support your gut health. Probiotics are “living microorganisms” that help restore balance in the intestinal microbiota by promoting the growth of good bacteria. Probiotics play a role in defining and maintaining the delicate balance between necessary and excessive defence mechanisms including innate and adaptive immune responses. The beneficial effects of probiotics have been demonstrated in many diseases.
Interest around the importance of gut health is growing and more people are becoming aware of the health benefits of probiotics, however less is known about the very important role of prebiotics. Prebiotics feed the good bacteria in your gut. The only way good bacteria can colonise and take over from the bad bacteria is if it's environment contains enough of the 'food' it needs to flourish. If you are considering a probiotic supplement, ensure that you take it alongside a supporting prebiotic.