It can be hard to imagine how the health of our gut can impact organs outside of our digestive tract, let alone our overall health. There is mounting scientific evidence demonstrating how the gut microbiome and other organs interact. An unbalanced gut microbiome has been linked to over 70 conditions. Everyone can benefit from looking after their gut.
Your gut is home to trillions of microorganisms collectively known as the gut microbiota. This includes good and bad bacteria, viruses, and fungi. The vast majority of microbiota is found in the caecum, a pouch that forms the first part of the large intestine.
One of the critical responsibilities of the gut microbiota is to break down the fibre we consume from plant-based foods. The digestive enzymes and hydrochloric acid in our digestive tracts are not strong enough to break down roughage from fruits, vegetables, nuts, seeds, and grains. The various species of bacteria that reside within our gut can ferment this fibre making digestion more comfortable.
The fermentation also provides a beneficial by-product called short-chain fatty acids. These by-products have many benefits, including improving nutrient absorption, providing energy for the cells of the digestive tract, supporting the integrity of the gut barrier, preventing the entry of harmful pathogens into the bloodstream, reducing inflammation, and helping to regulate appetite.
Our immunity is also tightly regulated via the gut. Our digestive tract is the most popular gateway into the body. Therefore 70% of immune tissue lives within our gut. The front-line defence consists of our intestinal wall, which acts as a physical barrier to foreign invaders, and the second-line protection is the immune system. This system involves a high-level network of cells, tissues, and organs that work together to fight off invaders.
An area of research that is particularly exciting is the link between gut health and brain health.
In the SMILES trial, participants who consumed a diet rich in fibre, fruits, vegetables, legumes, whole grains, and healthy fats experienced a significant reduction in their depressive symptoms, and 30% of the dietary intervention group achieved complete remission of their depression.
Another Australian study, The Gut Feelings trial, investigated the impact of a high prebiotic diet on mental health. The results showed that the group receiving the high prebiotic meal experienced a moderate improvement in psychological distress compared to the placebo group.
Sounds good but scratching your head, how can you improve your gut and overall health?
There are many ways to enhance your gut health, starting with your diet and increasing plant diversity. To support specific beneficial microbes within your gut, include more prebiotic-rich foods. Naturally occurring prebiotics in food is the best way to nourish your gut microbiome
Some of the best sources of prebiotics include almonds, cashews, legumes, brussels sprouts, asparagus, onions, and garlic. If you have a sensitive stomach, consider choosing low FODMAP options such as rolled oats, canned red kidney beans, or firm bananas.
Incorporating fermented foods into your diet can provide health benefits and unique flavour profiles. It's important to note that not all fermented foods impact our health positively or contain live microbes. Alcohol; we are looking at you.
However, the benefits of fermented foods can extend beyond the live microbes. For example, the microbes in sourdough bread die off during baking. But when compared to non-fermented whole wheat bread, it was shown to have a better response on participants' blood sugars.
Microbes, also known as probiotics, found in refrigerated products like yoghurt and kefir are more likely to benefit our health. Changing the balance of bacteria within the gut microbiome only takes twenty-four hours.
Remember, every bite of food can alter your gut bacteria :)
By Chelsea McCallum
Chelsea is an Accredited Practising Dietitian with expertise in Irritable Bowel Syndrome and the founder of The IBS Relief Program, a completely digital solution helping IBS sufferers from all over the world.
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