Wondering what to eat to keep your gut healthy? Our nutritionist shares the best foods for gut health, plus answers to a range of gut health questions
Summary
19 gut health supporting foods
Adding a few ‘gut-friendly’ foods into your daily diet could introduce a whole host of beneficial bacteria into your gut...
29 of the best fermented foods and drinks
Food fermentation can have some pretty tasty (and healthy!) results. Here are nine of our favourite fermented foods...
3"Free from” foods for a happy gut
Keeping your gut healthy is important for everyone – but it might be even more so if you have allergies or intolerances…
What should you eat to keep your gut healthy? And can bacteria really be good for you? With the help of nutritionist Isabel Tarrant, and her MSc in Clinical and Public Health Nutrition, we tuck into the science of digestion and reveal some of the best foods for gut health.
“We have approximately 100 trillion live bacteria living inside of us – this equates to 2kg of our body weight,” she says. “These helpful bacteria thrive by feeding off the food we eat. So, food is essential not only to feed and fuel us, but also to feed and fuel our friendly gut bacteria.” We’ll also distil the facts on fermented foods, plus how to include them in your diet to work towards a healthy gut.
What foods help gut health?
Gut health foods aren’t a magic solution but consuming them often can help keep your microbiome at its strongest and most diverse. Adding a few into your daily diet could introduce a whole host of beneficial bacteria into your gut. Read on for our top gut health-supporting foods...
Avocado
Not just a food trend, they’re packed with gut-supporting nutrients, too. As well as being a source of 'good' fats, one avocado contains a whopping 13g fibre, helping you on the way to a happy gut.1 But it doesn’t end there. Research conducted by the University of Illinois from 2020 found that trial participants who ate an avocado every day had a more diverse gut microbiome, which helps to break down fibre and produce gut-healthy metabolites.2 Need recipe inspo? What about our avo and egg bagel for a lazy weekend brunch at home?
Lentils
As we mentioned before, legumes are a great way to help your gut. With approximately 15g fibre per cooked cup, lentils are a great way to increase your fibre intake and provide support to improve your gut health.3 Scientists have recognised that lentils are a source of prebiotic carbohydrates, which are ingredients that allow for change in the makeup or activity of the gut microflora.4,5
Black beans
Perfect in a chilli, curries and stews, black beans are another great gut health-supporting food. With roughly 15g fibre per cooked cup, you won’t want to skimp on them.6 One study from 2020 found that the resistant starch in black beans increased the level of Clostridia class bacteria, a potential type of bacteria for probiotic use.7
Oats
Porridge has remained a classic breakfast for years and for good reason. Oats are one of the best foods that can help digestion, as there's 5g fibre per 50g serving.8 But it’s not just any kind of fibre. The type that is found in oats is called soluble fibre, but specifically one called beta-glucan. This has been shown to support gut health by increasing the level of 'good' bacteria in the gut (Lactobacilli and Bifidobacteria).9,10
Popcorn
Everyone’s favourite cinema snack is actually healthier than you might think. Who knew popcorn could be one of the best foods for gut health? Although – just to be clear – we’re not talking about the kind covered in butter, sugar and salt. Pure, air-popped popcorn without any added sugar, fats or chemicals contains an impressive 14.5g fibre per 100g.11
Chia seeds
Hailed as a superfood, chia seeds have become super popular in the health industry. We've particularly been enjoying them added to sweet desserts like this vibrant chia seed pudding. One of the main benefits they have to offer is their fibre content. In a 25g serving (or just under two tablespoons), there is approximately 8.6g fibre.12 Specifically, the fibre in chia seeds is also a soluble fibre. This means that it feeds the gut bacteria, helping it to work at its best.13
Almonds
As well as boasting 6.9g fibre in two servings (46 almonds), they’ve also been shown to have prebiotic effects on the gut.14 Scientists have observed that almonds can improve the microbiota profile and change intestinal bacterial activity.15
Garlic
The key to most delicious meals, garlic isn’t just good for the tastebuds – it’s potentially good for the gut, too. Some studies have shown garlic to help with the growth of bifidobacteria in the gut.16
Onions
Equally as important in cooking as garlic, onions also offer more bang for your buck than you might think. They’re a source of inulin (a type of fibre) and fructooligosaccharides (FOS – because we might need to shorten this one), which help to strengthen the gut flora.17,18
What vegan and vegetarian gut health foods are there?
You’re in luck when it comes to finding vegan foods that benefit your gut – there are plenty out there including:
- many fermented vegetables – like kimchi and sauerkraut
- fermented soy products, like tempeh and tofu
- kefir traditionally uses dairy milk but it’s possible to make it with your plant-based milk of choice (and you’ll find water kefir readily available)
- kombucha
If you’re vegetarian, you can enjoy milk kefir as well as other probiotic dairy products like live yoghurt and buttermilk. Miso paste is vegan on its own but be sure to check any pre-made miso soups as they traditionally contain fish.
Gluten-free foods for gut health
Lentils and black beans are both gluten-free, as well as being a great source of fibre, protein and encouraging health gut function. While they don’t contain any gluten themselves, always check the packaging to make sure the product you’re eating is labelled gluten-free (as traces can sometimes occur from cross-contamination).
Kefir is made from kefir grains but these aren’t actually grains at all. Made traditionally, kefir is gluten-free – but, again, check the packaging for any additives or flavourings containing gluten. Avocados are also a delicious and versatile gluten-free option that’s good for your gut.
What foods can negatively impact your gut?
Unless you’re sensitive to specific foods, you shouldn’t feel you have to cut anything out entirely for the sake of your gut health. The old rule is true: everything in moderation. However, there are some groups of foods that can have a negative impact on your gut microbiome, so it may be worth considering your intake if you’re looking to keep your gut health on top form...
Studies show that a high intake of sugar suppresses the growth of positive bacteria.22 As a result, you may expect a negative impact on your microbiome composition.
Common sweeteners, such as saccharin, aspartame and sorbitol, can prevent the growth of friendly bacteria in the gut.23 This can cause negative harmful bacteria to thrive.
Gut health FAQs
Fermented foods and drinks are made through a controlled fermentation process, where beneficial microorganisms, such as bacteria or yeast, naturally transform the ingredients.24,25 Interest in fermented foods has grown because of their potential health benefits, particularly for gut health. Some fermented foods contain live beneficial microorganisms and natural compounds produced during fermentation, which may help support a healthy gut microbiome by nourishing and working alongside the beneficial microbes that naturally live in your gut.24
Scientists are continuing to investigate whether fermented foods can help manage specific digestive symptoms, such as bloating, constipation and general GI wellbeing. While some studies have shown promising results,26 more high-quality research is needed before firm conclusions can be made.
Naturally fermented pickled foods (made with salt rather than vinegar) may contain live beneficial bacteria that may help support a healthy gut microbiome.27 In one 12-week study, women who ate traditional fermented pickles every day showed positive changes in their gut microbiome, and some types of fermented pickles were also linked to improvements in certain markers of inflammation. However, this was a single study in a specific population, so more research is needed to understand whether these benefits apply more broadly. Most supermarket pickles may not contain live microorganisms and aren’t typically expected to provide the same potential health benefits as naturally fermented pickles.
Not necessarily. Spicy food isn't harmful for everyone – and many people can enjoy it as part of a healthy, balanced diet without any digestive problems.28 However, if it triggers heartburn, stomach pain or diarrhoea, it's a good idea to eat less of it.28 If you have conditions like acid reflux or irritable bowel syndrome (IBS), spicy foods may make your symptoms worse, so it may be best to avoid them.28 There is no need to completely avoid spicy foods if you tolerate them well. Listen to your body and choose the level of spice which feels comfortable for you.
The final say
As early as our weeks in the womb, our gut microbiome has started to take shape. And by the time we’re earth side, the most important contributor to gut health is our diet. There are so many benefits to a happy tummy, especially since 90% of the ‘happy hormone’ serotonin is produced there. So, when it comes to rustling up your next recipe plan, why not consider putting a few of these gut-friendly and fermented foods on your plate?
Hungry for more? Here are seven ways to keep your gut healthy.
Disclaimer – This article provides informational advice and is not a substitute for medical care. Working with experts for accuracy, we take great care to ensure the information is up-to-date and relevant. However, you should always consult your GP or healthcare professional before using supplements or alternative products, particularly if you have medical conditions or are under supervision.
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