Gut instinct: the key to your health and wellbeing

The secret to ageing well could rest within your gut, which scientists now know plays a crucial role in important body systems, including immunity, metabolism and even how happy we can feel. Here’s how to maximise your gut health so everything else ticks along nicely.

Hippocrates gave us the heads up around 320BC when he said all disease begins in the gut. If only we’d taken his word for it. The good news is that science has caught up, and we now know that our gut microbiome – a term that describes the trillions of bacteria and microbes that live there – plays a crucial role in our health and sense of well-being. “The depth of the microbiota is hard to fathom,” says Will Bulsiewicz MD, a gastroenterologist and author of an excellent new book called Fiber Fueled. “The numbers are so astronomical … and it’s a wondrous magical community with amazing healing powers.” Even better, it’s possible to change the health of your gut with your next mouthful.

In the dark

Given the power the gut wields, it’s a wonder GPs don’t bang on about it constantly. Dr Bulsiewicz says that’s because this discovery is relatively new. We have known microbes live inside us for a long time (since 1683, to be exact), but our gut microbiome has resisted scientific breakthroughs because most of our microbes don’t survive on a petri-dish. Then in the early 2000s, researchers figured out how to sequence their DNA, and we started to learn.

“As recently as 10 years ago, there weren’t many research papers on the gut at all,” says Dr Beth Steels, a biochemical nutritionist. “Now, they are pouring in, and we’re constantly learning about the influence of our gut and how we can optimise it.” Researchers, looking at everything from obesity to depression and even Alzheimer’s, are connecting the dots between our gut and disease. Today, there’s little doubt left in the scientiftic community that our gut microbiome is the command centre for health in our body, including our immunity, hormonal balance, cognition and moods.

Trouble down below

There are many ways modern life makes it hard to optimise gut health. “Lack of variety in the average diet means that for many people, their microbiomes might be far less diverse than is ideal,” says Dr Steels. The excessive consumption of meat, alcohol and refined sugars deplete gut flora; as does the overuse of antibiotics, fad diets and stressful lifestyles. As for the ways this might play out in how you’re feeling on a daily basis, it could be intestinal (think bloating, constipation, gas) or extra-intestinal (anything from skin breakouts and weight gain to fatigue and difficulty concentrating have been attributed to an unhealthy gut microbiome).

They are what you eat

Put simply, your food is their food.

The catch is that not every microbe eats the same food. “Each dietary choice you make will empower a specific group of microbes, while others will languish,” says Dr Bulsiewicz. But they procreate so quickly it doesn’t take days or even weeks to change your microbes, it only takes one bite.

Once your microbes have worked through the food you’ve eaten, they mould our food into compounds that travel to every part of the body, reducing inflammation and promoting good health in countless ways. “The good bacteria keep your bad bacteria in check too,” explains Dr Bulsiewicz. “They multiply so often that the unhealthy kind don’t have space to grow.” Conversely, unhealthy foods create a chain reaction that has the opposite effect, creating compounds that lead to inflammation.

Friends in low places

Eating more fibre is the number one thing you can do for your gut. “Fibre is the heart and soul of true gut healing ... which leads to better health in everything from your cardiovascular systems to your brain and hormone health,” says Dr Bulsiewicz. More specifically, that means eating fibre-rich plants including fruit, veggies, wholegrains, beans and legumes (also known as soluble fibre or prebiotics, which describe foods or supplements that promote the growth of beneficial micro-organisms). “The single greatest predictor of a healthy gut microbiome is the diversity of plants in your diet.”

In one of the most diverse studies of microbes and microbiomes of the industrialised world, it was discovered the greatest predictor of a healthy gut was the consumption of 30 different plants in a given week (that includes grains and legumes). “This really goes back to the message you’ve heard many times before,” says Dr Steels. “And that is, eat as many whole and unprocessed foods as possible.”

For most people, this needs to be a conscious decision, given that research shows nearly 60 per cent of all calories humans obtain from plants come from rice, maize and wheat. “When you maximise plant-based diversity, you choose foods that nourish and sustain your optimal health rather than foods that zap your energy and beat up your gut microbiota,” says Dr Bulsiewicz.

In a pickle

You’ve likely heard the wellbeing buzzword “probiotics”. This simply describes live micro-organisms that benefit the body when consumed. They are found throughout our system (including the gut, lungs and vagina), the supplement aisle of your local chemist, and most importantly, fermented foods.

“Every single culture in human history has fermented food as part of their food tradition,” says Dr Bulsiewicz. There’s sauerkraut from Germany, kvass from Russia and kimchi from Korea, to name a few. “Sadly we have let go of our traditional foods in exchange for hyper-sterile, chemical-laden conventional foods offered up by our food industry.” A better idea: eat more fermented foods, which also include miso, sourdough bread and kombucha too. “Fermentation is one of the rare examples of food processing that actually makes our food even healthier,” says Dr Bulsiewicz, noting they can improve insulin sensitivity, improve fullness after meals to promote weight loss and lower blood pressure and cholesterol.

“At the end of the day, if you start making food choices with your gut microbiome in mind, research tells us you will be healthier, happier, and protect your body from a number of degenerative diseases,” says Dr Steels. “The world is changing from only focusing on this part of our body when we’re in discomfort, to one where this is a priority for anyone who wants to be healthy and well.” Pass the porridge, please.