We need fibre for a healthy digestive system. It’s often described as being like a natural scrubbing brush because it cleans our insides and keeps waste moving smoothly through the body.
There’s also mounting evidence to suggest that fibre may lower the risk of heart disease, stroke, bowel cancer, and type 2 diabetes. Plus, because it can’t be broken down by the body and remains intact as it passes through our intestines, fibre can keep us fuller for longer.
When it comes to getting enough fibre, many of us will think of cereals such as Weetabix, Fruit ‘n’ Fibre, and Shredded Wheat, which are regularly promoted for their high-fibre content. But what other foods are there?
The NHS advises that it’s best to get fibre from a variety of sources to build as balanced a diet as possible.
Below, we’ll take a look at more fibre-containing foods – as well as delving deeper into what fibre is and its benefits.
What is fibre?
American doctor and grain manufacturer, J.H. Kellogg, was one of the first to recognise the importance of fibre after he developed an interest in wheat bran. His research confirmed its positive impact on patients with colitis and constipation.
Since then, multiple studies and reports on the effects of fibre have reinforced its role in gut health.
So what exactly is fibre?
Fibre (sometimes known as roughage or bulk) is a complex carbohydrate that occurs naturally in plant foods, and can’t be digested or absorbed by the body.
While there are various different types of dietary fibre, the main ones we need for a healthy digestive system are soluble and insoluble fibre.
Soluble fibre
Soluble fibre attracts and dissolves in water, forming a gel-like substance (similar to what happens when you mix oats and water). It collects bile, cholesterol, hormones, and metabolic waste products as it moves through the intestines (scooping them up like a net) to help rid them from the body.
Soluble fibre also slows digestion and the rate at which you can absorb sugar from the foods you eat. This helps to prevent blood sugar spikes – something which is particularly important when it comes to managing diabetes.
When soluble fibre reaches the large intestine (or colon), it’s fermented by healthy gut bacteria to produce short-chain fatty acids, which feed and nourish the gut microbiome. We receive a very small number of calories from this process (roughly two calories per gram).
Insoluble fibre
Insoluble fibre doesn’t dissolve in water and remains more or less unchanged as it moves through the intestine. It adds bulk to our stools to make them easier to pass and prevents constipation.
Insoluble fibre contains no calories because it can’t be digested so it doesn’t get broken down into energy.
What are the benefits of fibre?
While fibre might not receive as much attention for its nutritional value as many other foods, it still has plenty of other impressive benefits.
We’ve already mentioned that fibre can clean out our insides and keep our bowel movements regular. But what else can it do?
Dietary fibre can help with weight loss and maintenance
Fibre-rich foods tend to be lower in calories. However, because we digest them more slowly than simple starches and sugars, they help to keep us fuller for longer – meaning we’re likely to eat less. It makes sense then, that research has found dietary fibre to be a healthy tool for weight loss and maintenance.
For example, this study compared the eating habits of two groups of people; one group was considered obese and the other was classified as being normal weight. It was found that the normal weight group ate more fibre than the obese group.
A different study looked at four groups of people who were each on a different calorie-restricted diet. Each group was asked to exercise for 90 minutes a week while increasing their fibre intake at intervals. Interestingly, all groups lost the same amount of weight, regardless of which calorie-restricted diet they were on – suggesting that increasing your fibre intake can help you lose weight.
Dietary fibre can reduce inflammation and boost good gut bacteria
An estimated 70-80% of our immune cells live in the gut microbiome, and what we eat and drink directly affects these cells.
For example, some foods – such as processed and red meat, and refined carbohydrates like bread and pastries – can trigger an inflammatory immune response in the gut, which can then disrupt the balance of good and bad bacteria.
Research suggests that having too many bad bacteria in your gut can lead to conditions such as Crohn’s disease, ulcerative colitis, and irritable bowel syndrome (IBS).
In an interview with the National Gaucher Foundation, clinical nutritionist Lori Bard, says, “You can think of it as a bacteria community. The community includes good guys, bad guys, and indifferent guys. And in our body, these bacteria rule the school,” Bard explains. “Ultimately, the health of our microbiome determines our overall health.”
Therefore, increasing our fibre intake can help to nourish healthy gut bacteria and keep their numbers strong so they can keep bad bacteria in check.
Dietary fibre can lower the risk of type 2 diabetes and blood pressure
Recent research suggests that a diet high in fibre could significantly improve the health of people with type 2 diabetes and high blood pressure, and lower the risk of these conditions developing in the first place.
In one study, 200 people with diabetes and hypertension (average age 50) ate 38g of fibre a day for six months and saw a 15% reduction in systolic blood pressure and a 28% reduction in fasting blood sugar.
A review of several studies also found that across a sixteen-meta analysis comparing the highest versus lowest fibre intake, there was a significant reduction in the relative risk of type 2 diabetes with the greatest benefit coming from cereal fibres.
Dietary fibre can lower the risk of heart disease
A high-fibre diet has been linked to a lower risk of heart disease and stroke. Scientists believe this is due to its ability to lower cholesterol and blood pressure and help us maintain a healthy weight.
This review revealed that soluble fibre (particularly beta-glucan and psyllium) lowers the risk of heart disease the most.
Dietary fibre may reduce the risk of developing bowel cancer
Mounting research suggests that eating a high-fibre diet could help to reduce the risk of bowel cancer – as well as breast, ovary, endometrial, and stomach cancer. In fact, Cancer Research has emphasised that 28% of bowel cancer cases in the UK are caused by eating too little fibre.
The main suggestion for reasons why is that a high-fibre diet encourages more regular bowel movements, meaning that harmful chemicals spend less time in our bodies.
Plus, when fibre combines with healthy gut bacteria, it forms a short-chain fatty acid called butyrate, which supports a healthy digestive system so that the development of tumours is less likely.
As we know, fibre can also help us to maintain a healthy weight – and according to Cancer Research, 11% of bowel cancer cases are caused by being overweight or obese.
Dietary fibre has been linked to a longer life
One study looking into the effects of a high-fibre diet on longevity found that people who eat more fibre had a 23% lower risk of dying from any cause, compared to those who ate little or no fibre.
Other research has also revealed that for every 10g increase of fibre per day, your risk of mortality could reduce by 10%.
Dietary fibre can improve bone health
Inflammation in the body can be harmful to our bones – increasing the risk of fractures. So it makes sense that fibre’s anti-inflammatory properties would make it a great advocate for healthy bones.
In fact, scientists have found that people who eat a high-fibre diet have lower levels of C-reactive protein (CRP) – an inflammatory marker linked to diseases like rheumatoid arthritis, heart disease, and diabetes.
Studies have also shown that soluble fibre can help us better absorb bone-boosting minerals, like calcium, in the gut.
10 easy ways to add more fibre to your diet
Government guidelines say that adults should eat 30g of fibre per day – though most adults only eat around 20g, on average.
There are no specific recommendations on how much we need for each type of fibre. Instead, experts say that we should focus on the total amount of fibre we consume each day.
If you’re concerned you’re not getting enough fibre, you might want to try some of the following tips…
1. Switch to whole grain versions of staples like bread, pasta, and rice
Whole grains are much higher in fibre than refined grains. This is because whole grains contain the entire grain; made up of bran, germ, and endosperm. The bran is the fibre-rich part – but this is removed from refined grains (along with the germ) during the milling process.
Therefore, it’s better to choose whole grain or granary bread over white bread; whole wheat pasta over regular pasta; and brown rice, wild rice, bulgar wheat, and barley over white rice.
2. Swap juice for whole fruits and vegetables
Though juice can contain plenty of vitamins and minerals, even the cold-pressed and unpasteurised versions are stripped of fibre during the juicing process. What’s left is a concentration of carbs; specifically sugar.
Vegetable juices contain less sugar than fruit juices. But they still don’t contain as much fibre as the complete vegetable.
While juices can be enjoyed in moderation as part of a healthy diet, it’s better to eat whole fruits and vegetables for maximum nutritional benefits.
3. Eat popcorn
Popcorn is a whole grain, which means it’s high in fibre. Plus, it can be prepared quickly and makes for a great snack. It’s estimated that 100g of popped popcorn contains a huge 15g of fibre (half the recommended daily intake).
Popcorn is also rich in magnesium (which supports muscle and nerve function, and energy production), manganese (which helps the body to form blood clotting factors, connective tissue, bones, and sex hormones), and phosphorus (needed for growth, maintenance, and repair of tissues).
Making your own popcorn at home is one of the healthiest ways to enjoy it, as cinema and shop-bought varieties tend to be full of fat and sugar. Before you get poppin’, you might want to check out these healthy popcorn recipes from Eating Well.
4. Choose high-fibre breakfast cereals
Breakfast cereals are well-known for their high-fibre qualities – however, not all cereals are created equal.
Options such as Special K, Cheerios, and Cornflakes contain low amounts of fibre, while cereals like wheat bran (9.8g fibre per 40g), bran flakes (7.3g per 40g), and shredded wheat pillows (4.6g per 40g) are the most fibre-rich.
Like popcorn, cereals can also be loaded with fat and sugar so it’s important to check ingredients carefully. Health experts recommend steering clear of cereals which list the following in the first three ingredients: sugar, corn syrup, brown rice syrup, maltose, fructose, glucose, maltose, dextrose, and maltose.
5. Eat the skin of fruits and vegetables
Research suggests that unpeeled fruits and veggies may contain significantly higher amounts of fibre than those without peel. Fruit and vegetable peels also tend to have more vitamins, minerals, and antioxidants than the flesh.
It’s always best to wash fruit and vegetables before eating them, whether they’ve been peeled or not, to rinse off any dirt, bacteria, and pesticides. It’s also worth being aware of which peels are considered safe to eat.
Kiwis, potatoes, carrots, and courgettes have edible, fibre-rich skins; while avocado, melon, and tropical fruit (like papaya and lychee) have inedible skins. You can find out more about the benefits of eating fruit and vegetable skins and which to eat in this article from Healthline.
6. Experiment with different ways to use beans and lentils
Lentils and beans are some of the most highly nutritious foods out there – with fibre being one of their most abundant ingredients.
Lentils contain roughly 15.6g of fibre per cooked cup, while haricot beans contain 19.1g of fibre, and black beans contain 15g.
You can add lentils and beans to soups, stews, and salads. Or, for more delicious ways to eat them, check out this article by Cookie and Kate, which includes recipes for everything from Lebanese lemon-parsley bean salad to spiced vegan lentil soup.
7. Eat chia seeds
Chia seeds may be tiny but they’re a leading source of fibre, with 28g of chia seeds containing close to 10g of the good stuff. They’re also packed with omega-3 fatty acids, antioxidants, and minerals.
Another great thing about these mighty seeds is that they’re incredibly versatile. They can be added to salmon to form a crusty coating, turned into a chia pudding, or sprinkled on porridge.
Our article, 7 health benefits of chia seeds and how to use them, has plenty more ideas.
8. Add a portion of veg to every meal, and eat it first
Most of us know that we should be eating at least five portions of fruit and vegetables a day but this can be easier said than done. Often, veggies are also an afterthought on our plates – something we eat towards the end of our meal if we’re not too full.
For this reason, it can help to add vegetables to every meal and eat them first, to make sure you get enough of them. One study showed that when people ate a salad before their meal, they ate 23% more veggies than those who were given salad along with their main meal.
Some of the most fibre-rich vegetables you might want to include in your meals are potatoes (including sweet potatoes), aubergines, carrots, and avocados.
9. Use berries as a topper for cereal and yoghurt
Berries like strawberries, raspberries, blueberries, and blackberries are low in calories and high in fibre – and they make the perfect, tasty topper for cereal and yoghurt.
To give you an idea, one cup (144g) of whole strawberries provides 3g of fibre. So while they may not provide the bulk of your daily intake of fibre, they can certainly help to boost your intake.
Another fruit that’s high in fibre, which adds a wonderful, tropical flavour to porridge and yoghurts is passion fruit. Passion fruit contains a whopping 25g of fibre per cup.
10. Snack on fruit, nuts, and seeds
As well as eating more fibrous meals, you can also top up your fibre intake by carrying fibre-rich snacks with you. Things like fruits, nuts, and seeds are easy to eat on the go and will generally keep you satisfied for longer in between meals than sugary or processed foods.
Apples, pears, oranges, bananas, and berries make excellent high-fibre snacks, as do almonds, chestnuts, and pumpkin seeds.
Final thoughts…
Fibre makes up an essential part of a healthy diet. Not only does it protect and support our gut but it may also reduce our risk of developing type 2 diabetes, heart disease, and certain cancers.
If you think you might not be eating enough fibre, then hopefully some of the diet tips in this article will be useful. Many of the foods mentioned here also offer far more than a good dose of fibre – they also provide important vitamins, minerals, and antioxidants – so by eating them, you’ll be improving your overall health too.
For more healthy diet tips, you might want to visit the diet and nutrition section of our website. Here, you’ll find articles on other important nutrients, like vitamin D and magnesium.