You may think your gut’s only priority is to keep your digestive system happy and healthy, but its responsibilities actually extend far beyond that. You see, there’s a bustling ecosystem of bacteria and neural network functioning in your gut. It houses 100 million neurons, cultivating what researchers are now calling your ‘second brain’ i. This isn’t a ‘thinking’ brain as we know it – it doesn’t solve mathematical problems, write literature, or reason – yet data points to it having the power to influence mood and emotional wellbeing. Some studies even linking poor gut microbiome with anxiety and depression ii. It’s worth noting that gut health and your immune defences are intimately connected, too. In fact, 70 to 80 per cent of your immune tissue is located in the digestive tract. Clearly, then, adding more gut-friendly foods to your diet could benefit countless areas of wellbeing besides digestive health.
You need two lines of attack to properly nourish your gut: probiotic and prebiotic foods. Despite sounding similar, these buzzwords aren’t to be confused; they play very different roles in your gut. ‘Probiotics’ are bacteria that have similar credentials to the ‘good bacteria’ colonies already in your gut. ‘Prebiotics’, on the other hand, act as the fuel feeding these bacteria – think of them as probiotic fertiliser. Eating a balanced amount of both probiotics and prebiotics is the secret to keeping your gut fighting-fit all year round.
Probiotics
Embracing more of these probiotic-rich, fermented foods will bolster your gut health and support everything from weight loss and immunity, to emotional wellbeing and digestive health.
Miso
Sure – this fermented soybean-based paste may be high in sodium, but thanks to it containing the probiotic strain, A. oryza, it’s a magic bullet for your gut microbiome iii. In fact, miso is so darn good for gut health that Japanese people always start their day with a bowl to stimulate digestion. It packs impressive amounts of iron, calcium, magnesium and protein, too. Add a spoonful of miso paste to warming broths and soups. And for a mouth-wateringly moreish salmon marinade, combine miso with soy sauce, sesame oil and vinegar.
Kefir
A staple of Eastern European diets, kefir is another powerful weapon for gut health. Tart, sour and slightly ‘fizzy’, this fermented milk drink contains around 61 strains of yeasts and bacteria, making it an immensely diverse and rich probiotic source iv. Though you can now find bottles of kefir lining the dairy aisle of supermarkets and health food shops, it’s very easy to make your own batch at home. Vegan? Lactose-free? Don’t worry – you can still reap the benefits of kefir by swapping cows milk for coconut milk.
Kimchi
Kimchi, a delicacy in Korean cuisine, is a traditional dish of salted, fermented cabbage and radishes. Besides adding a kick to meals, this condiment bolsters the friendly bacteria in your gut, too. In fact, any probiotic made with cruciferous veggies, like cabbage and garlic, will support digestion and help the body eliminate toxins v. Added bonus: the rich fibre content in our probiotic pal may also regulate bowel movements and prevent constipation. You can enjoy kimchi on its own, mixed with brown rice, or in a classic Korean dish called ‘bibimbap’.
Sauerkraut
Sauerkraut is yet another probiotic powerhouse. Not only is this fermented cabbage dish abundant in calcium, potassium, and vitamin C and K, but it’s also jam-packed with beneficial bacteria to nourish your gut. Better still, sauerkraut contains powerful enzymes that help the body process food more easily, thereby improving the absorption of nutrients vi. A small serving of sauerkraut can seriously crank up the nutritional value and zing of any meal.
Apple cider vinegar
Made from fermented apple sugars, ACV is truly a ‘jack-of-all-trades’ in the wellness world, boasting impressive beauty and health credentials. The acetic acid in this kitchen staple works wonders for digestion. ACV has even been shown to lower the growth of the negative bacteria Staphylococcus aureus and Pseudomonas aeruginosa in the gut vii. Oh, and did we mention it boasts antimicrobial qualities, too? Just another noteworthy feature that bolsters gut microbiome and immune defences. ACV is the perfect way to spice up traditional salad dressings.
Kombucha
There’s good reason this fermented tea beverage is now being served on tap in many establishments – it’s brimming with powerful probiotics that bolster gut heath, digestion and inflammation viii. It’s also chock-full of immune-boosting antioxidants and B vitamins. Like kefir, you can brew you own kombucha at home. However, it’s only healthy when prepared properly; contaminated kombucha can trigger a host of health problems. Fortunately, there’s no shortage of tasty kombucha on the market. You may need to sample a few brands find your favourite.
Yoghurt
As a fermented food, yoghurt naturally contains tons of probiotic cultures that support your digestive tract. But while traditional yoghurt is great for your gut, Greek yoghurt takes the biscuit. You see, this thick, creamy treat is loaded with the potent probiotics Lactobacillus casei and Lactobacillus acidophilus ix. Yoghurt is the perfect canvas for seeds, nuts, fresh fruit or even a little granola. Plus, it’s extremely satiating, making it a great option for breakfast or as an afternoon snack. You need to become an ingredient sleuth when shopping for yoghurt – watch out for anything with hidden preservatives or added sugar.
Tempeh
A delicious, nutrient-dense alternative to meat, this soybean protein is crammed with probiotics to nourish your gut, as well as support digestion x. But that’s not all – tempeh serves up a healthy amount of polyunsaturated and monounsaturated fats, too. It also comes with the added bonus of being immensely protein-rich, meaning it will leave you feeling satisfied and full. Enjoy tempeh in stir-fries or with healthy grains, like quinoa or brown rice.
Prebiotics
To unlock the full gut-boosting potential of these probiotic powerhouses, you need to eat prebiotic foods, too. Think of them as probiotic’s vitally important energy source.
Chicory root
Chicory root is an abundant source of prebiotics. In fact, roughly 47% of chicory root fibre comes from the prebiotic fibre, inulin. Its noteworthy prebiotic qualities feed friendly gut bacteria, improve digestion and may provide some relief from constipation xi. You won’t usually find chicory root in its raw form, but you can certainly find it ground up, ready to inject some spice into your meals and baked goods.
Jerusalem artichokes
Otherwise known as the ‘earth’s apple’, Jerusalem artichokes offer a host of benefits for gut health. This rich prebiotic not only fuels the friendly bacteria in your colon, but it strengthens your immune system, too xii. It delivers around 2 grams of dietary fibre per 100 grams – of which, 76% comes from inulin. Enjoy Jerusalem artichokes in soups, salads or roasted with plenty of garlic and rosemary.
Garlic
Besides adding a burst of flavour to dishes, this pungent bulb acts as a potent prebiotic in your gut, promoting the growth of the beneficial bacteria Bifidobacteria xiii. Around 11% of the fibre content in garlic stems from the prebiotic inulin, while 6% comes from a naturally occurring prebiotic called fructooligosaccharides (FOS). To optimise garlic’s prebiotic capital, it’s best eaten raw. A good reason to put up with garlic breath, right?
Onions
This versatile veggie doesn’t just take pride of place in soups, stews, and sauces; its impressive prebiotic properties also work wonders for your gut health. Like its cousin, garlic, FOS makes up around 6% of its total fibre content, while inulin accounts for 10%. FOS supports the gut flora, immune system, digestion and provides fuel for your microbiome xiv. When in doubt, throw in an onion – it makes an appetising addition to almost any meal.
Leeks
As a member of the onion family, leeks contain 16% of inulin, which positively impacts the growth of good bacteria in your gut xv. Alongside this, leeks are abundant in flavonoids – compounds that reinforce your body’s response to free radical damage – and vitamin K, which supports the health of your heart and bones. Leeks are superstars in pasta, savoury pies and soups. Give ‘em a whirl and enjoy their sweet, earthy tones.
Asparagus
Not only do these tall, regal fellas mark the beginning of summer, but they also pack a punch to gut health. Though their inulin content is only around 2-3 grams per 100 grams, they still do a good job at feeding the friendly bacteria in your gut. Their rich antioxidant and fibre credentials are thought to offer anti-inflammatory support, too xvi. Munch on these verdant veggies raw, or grill them with a good squeeze of lemon before serving.
References:
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Keri
Keri Filtness has worked in the Nutrition Industry for 19 years. She is regularly called upon for her professional comments on health and nutrition related news. Her opinions have been featured by BBC3, Prima, Vitality, The Mirror, Woman’s Own and Cycling Weekly, amongst others. She has also worked one to one with journalists, analysing their diets and health concerns and recommending changes and additions, where appropriate.
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