28 Feb 2022 • 5 min read
What foods are good for gut health? Can bacteria really be good for you?
In this article, we delve into the science of digestion and reveal 9 of the best foods and drinks for gut health, including a few extra tips and tricks for maintaining a healthy gut.
The gut is a nine-metre-long tube that starts at the mouth, moves from the oesophagus to the stomach, through the small and large intestines, and ends at the back passage.
It’s where digestion takes place, and this involves three important processes:
Within the gut exists a thriving community of bacteria. As well as aiding digestion, they provide essential support for immune functioning, your skin, and brain health.
“We have approximately 100 trillion live bacteria living inside of us – this equates to 2kg of our body weight,” says Eliza Glynn, Holland & Barrett nutritionist.
“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.”
“Diversity in our gut bacteria is just as important as the number. The more species we have, the more health benefits we are likely to experience.
We need to make sure we’re fuelling all the helpful bacteria by eating a diet full of a variety of different foods.
Each species will feed off something different – and they can be just as picky as we are when it comes to their food.”
That’s why foods to improve gut health are so important to consider, but how does what happens in our gut impact on our overall health and wellness?
A staggering 70% of our immune cells are in our gut.1
As a result, problems in your gastrointestinal tract can make you more susceptible to feeling run down or picking up illnesses.
“Friendly bacteria produce metabolites, such as short-chain fatty acids. They play a crucial role in regulating T cells – the key peace-keeper cells of our immune system,” says Eliza.
“Moreover, our gut bacteria produce compounds which support the healthy functioning of white blood cells, known as macrophages. They are key for fighting off infections and harmful germs.”
Handpicked content: The expert guide to understanding immunity.
The health of your gut microbiome impacts cognitive function and mood. This is down to a two-way relationship between the gut and the brain known as the gut-brain axis.
“Bacteria in the gut modulates the activity of various chemicals in the brain, known as neurotransmitters. For example, it’s estimated that 90% of the ‘happy hormone’, serotonin, is made in the gut,” Eliza explains.
“Research shows that individuals suffering from anxiety, depression and autism tend to have a greater imbalance in their gut, with more negative bacteria than positive, compared to healthy individuals.”
Handpicked content: How the brain and the gut are connected
There’s a strong relationship between the composition of your gut bacteria and sleep quality.
“Imbalances in the gut microbiome are associated with increased risk of sleep disturbances and poorer sleep quality,” says Eliza.
“This is due to the interaction between gut bacteria and the regulation of sleep hormones.”
Gut bacteria produce compounds known as short-chain fatty acids (SCFAs), which influence the production of the hormones responsible for the feeling of hunger and fullness.
“Individuals with a healthy gut bacteria composition tend to also produce more SCFAs, which leads to reduced hunger and increased fullness,” Eliza says. “This has a direct impact on eating habits and weight.
Research shows a striking difference between the gut bacteria of overweight and lean individuals.”
Wellness benefits of a healthy gut may include:
It’s estimated that at any one time, about 4 in 10 people have at least one problematic digestive symptom.2
These symptoms typically come in the following ways:
Leaky gut syndrome, also known as “leaking gut syndrome,” is when our gut lining - normally a tight barrier that controls which nutrients are absorbed into the bloodstream - develops gaps that may allow partially digested food or toxins to get through.3
Symptoms of leaky gut syndrome may include:
Leaky gut syndrome can be treated or managed with a careful diet.
A good diet for leaky gut syndrome includes many of the same recommendations as those looking to improve their gut health more generally, with a selection of foods and drinks that are high in prebiotics and probiotics.
We’re going into these next, so get ready to take notes.
Read on to find out more about the best foods for a healthy gut...
High-fibre foods help to feed gut bacteria, allowing them to thrive and grow, important for improving and maintaining a healthy gut.4
Some nutritionist recommendations include:
The different phytochemicals found in coloured fruits and vegetables can help to encourage the production and stability of a diverse range of positive bacteria in your gut, reducing inflammation and creating a positive environment for gut health.5
“Plant-based diets are often better for the gut microbiome as they are naturally higher in fibre and phytochemicals,” says Holland & Barrett nutritionist, Eliza Glynn.
Prebiotic foods such as garlic, onion, chickpeas, beans, artichoke, bananas, leeks, milled flaxseeds (can be sprinkled on cereal, porridge, or added to foods), and oat bran (can be used to thicken soups and stews instead of corn-starch) are special fibres which good gut bacteria love to feed on.6
They’re “pre” biotic as they are not made up of live bacteria, but rather help to feed your microbiome’s existing bacteria.
If you’re struggling to get enough prebiotic foods into your diet, inulin powder can be added to sweeter foods or breakfasts as a helping hand.
You might like: Inulin Powder 200g (Vegan)
Sauerkraut is a national dish of Germany, made by fermenting finely cut raw cabbage in multiple lactic acid bacteria.
It is filled with good bacteria and has been proven to reduce inflammation.7
However, some studies have seen participants suffer from diarrhoea if eating sauerkraut too regularly.
Kimchi is like Korea’s version of sauerkraut.
This side dish is made of salted and fermented vegetables, such as cabbage, radish, spring onions, garlic, ginger, and various seasonings.
As it is also fermented in lactic acid bacteria, it has been proven to support gut health.8
Sauerkraut and Kimchi not to your taste? Try sourdough bread as a gentler way of getting beneficial bacteria into your diet.
Miso is another fermented product, this time made by fermenting soybeans.
Not only does it help to support your microbiome by being packed with good bacteria, but it also helps your gut to produce vitamins K and B12, helping your body to heal and regulate metabolism and energy.9
Kefir is a fermented milk drink that has a similar consistency to runny yoghurt.
It is made from kefir grains and is incredibly popular for its versatility and ability to aid digestion, reduce inflammation, and even strengthen bones as a source of calcium.
These antioxidants are found in certain plant foods, including berries, purple carrots, spinach, grapes and dark chocolate.
Black rice and dark beans are another good source and it’s the polyphenols that give black rice and beans their colour.
Selected dried fruit, such as raisins, are also high in polyphenols as the drying process concentrates polyphenol content.
As a large amount of polyphenols are only broken down and absorbed once they reach your large intestine, they help gut bacteria to produce compounds that support immune functioning, brain health, and digestion.
You might like: Holland & Barrett Black Rice 500g
If you may not be getting enough good bacteria through your diet, you can choose to take probiotic supplements with a variety of bacterial strains and a high potency of bacteria.
You might like our: Holland & Barrett Live Friendly Bacteria 20 Billion 60 Capsules
Read on to find out more about the best drinks for a healthy gut...
Green tea is often recommended to aid digestion and promote gut health, and there’s a reason for this.
According to a review of studies linking green tea to a healthy gut, green tea can “influence the gut microbiota by either stimulating the growth of specific species or by hindering the development of detrimental ones.”10
“White tea can be an alternative to green tea, as this can be an acquired taste. White tea is more mellow and some people may prefer it to the bitterness of green tea.
However, intakes of both should be limited due to caffeine content.
Coffee alternatives such as these are a good source of polyphenols and prebiotics as most are sourced from chicory or rye,” suggests Holland & Barrett nutritionist, Alexander Thomson.
Remember how the good bacteria in kefir can support our gut health? Well, it’s as simple as swapping milk with kefir in your favourite milkshakes and smoothies.
Fruit and vegetable smoothies are packed with all kinds of nutrients and vitamins, so blending a few of your favourites together for an on-the-go smoothie is perfect, especially as they help to keep the bacteria in your gut diverse, important for gut health.
Even if it’s not your favourite pre-meal habit, the lactic acid bacteria within apple cider vinegar is believed to promote healthy levels of beneficial gut bacteria, aiding digestion and reducing the risk of bloating.
Fermented soybean milk, which offers an alternative to dairy for those who are vegan or lactose-intolerant, promotes the growth of good bacteria such as Bifidobacteria and lactobacilli with its high protein and fibre contents.11
In the same way that polyphenol-rich foods support your gut health, a glass of red wine - also high in polyphenols—has been shown to increase levels of beneficial bacteria.12
Miso soup contains all the goodness of miso paste used in food to create a warming broth filled with flavour and good bacteria, specifically a probiotic named oryzae, which supports a healthy gut.13
Superfood powders take all the superfoods for gut health and turn them into convenient powders that can be blended with drinks, smoothies, soups, and more.
In this way, they help you to easily increase the good bacteria supporting your microbiome.
You might like our: Bioglan Digestive Boost 70g
Similar to probiotic supplements and powders, a probiotic drink could be your shortcut to a healthier gut.
If you find yourself struggling to increase your beneficial bacteria via the prebiotic and probiotic options in your diet, this could support your ongoing health goals.
Here’s the good news! As you’ll have probably noticed if you’re vegetarian or vegan, pretty much all the best recommendations of food and drink for gut health happen to be naturally suitable for you.
Although vegans will want to avoid dairy-based options, such as kefir, there are many dairy-free yoghurts available and soy-based or coconut kefir products are becoming more available every day.
Chew slowly - If you chew too quickly, food spends more time in your stomach, potentially increasing your risk of indigestion and heartburn.14 Additionally, eating quickly while talking may mean you swallow air and increase your chances of bloating and wind.15
Controlled portion sizes - Overeating only leads to discomfort and lethargy, neither of which will have your gut or your mind feeling healthy. By controlling your portion sizes, you can get the energy you need to stay active throughout the day—proven to improve gut health16—without the temptation of an afternoon nap.
Eat 3-4 hours before you go to bed - In a 2003 study, it was found that stomach gas reduced more quickly when participants were upright compared to laying on their backs.17 Make sure you leave enough time between your evening meal and bedtime for your gut to digest.
Read on to find out about the four worst foods for your gut...
Alcohol strips the gut of positive bacteria and promotes the growth of negative microbial species. This results in an imbalance in gut bacteria that can have a negative impact on immune functioning, digestion, sleep, mood, and weight.
Studies show that a high intake of sugar suppresses the growth of positive bacteria. As a result, you can expect a negative impact on your microbiome composition.
Natural sugar substitutes from our nutritionists: “Xylitol or coconut nectar can be used in the place of sugar and reduce effect on gut health without losing the sweetness.
Expert tips on reducing sugar: “Snack on dried fruit to satisfy the sugar craving and lower sugar intake simultaneously. Added benefits include high fibre and polyphenols.”
Common sweeteners, such as saccharin, aspartame, and sorbitol, can prevent the growth of friendly bacteria in the gut. This can cause negative harmful bacteria to thrive.
“Protein from a meat-based diet negatively affects your gut’s microbiome.
Good and varied plant sources of protein ensure intake of all essential amino acids, while plant-based protein sources typically also provide good levels of fibre,” says Eliza.
Put simply, the healthy, friendly bacteria in your gut need a constant supply of nutrients to multiply and flourish.
By eating a wide variety of whole, unprocessed foods, including fibre, prebiotics, probiotics, and a wide range of fruit and vegetables, you’re choosing the right food and drink for gut health.
The advice in this article is for information only and should not replace medical care. Please check with your GP or healthcare professional before trying any supplements, treatments or remedies. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle.
Last updated: 28 February 2022