What is dietary fibre?
There is a lot of talk about the importance of eating fibre because of all the health benefits they bring, but what is dietary fibre.
Dietary fibre is the part of the plant that can’t be digested by our enzymes nor absorbed in the small intestine which means that it reaches the large colon intact.
Categorisation of dietary fibre
There are different types of dietary fibres and they’re often categorised by their different characteristics and the most common way is to do this by their solubility.
Soluble – Dissolve in water and are gel forming. These types of fibres have a good effect on lowering blood sugar levels and are often fermented in the gut. Found in fruit, legumes, oats, barley and vegetables.
Insoluble fibre – Does not dissolve in water and basically stay intact from when they enter the mouth to all the way out. These types of fibre help to add bulk to the stools and can promote regularity. Found mainly in whole grains but also in vegetables and fruits.
Categorising fibre by its solubility is not really practical as it doesn’t always reflect the properties of a certain type of dietary fibre.
That’s why fibres are more often being categorised by their fermentation properties and viscosity.
Fermentability– To what extent the fibres are being fermented (digested, broken down) by the bacterias in your gut. Fermentable fibres promotes the growth of good bacterias in the gut.
Viscous – This means how gel-forming the fibre is. This can slow down the transit and the digestion of the food, which can help to keep you fuller for longer and also keep your blood sugar levels balanced.
Generally, soluble fibres are viscous and fermentable, but there are also insoluble fibre that are fermentable and viscous, which is why categorising on solubility is not always relevant!
For example, chia seeds contain soluble fibres but mainly insoluble fibre and it’s highly viscous (gel-forming) as many of you may know if you’ve ever made a chia pudding!
Most foods you eat you eat though contain a mixture of these types of fibre and both of them are beneficial to us!
Benefits of eating dietary fibre
- Promotes a healthy microbiota – Eating fibres promotes the growth of good bacterias in our gut that can have health promoting effects
- Supports the immune system – A healthy gut microbiota can help to protect the body against harmful pathogens and and help with the regulation of the immune system.
- Balance blood sugar levels – As fibres are not digested, they will not affect the blood sugar despite being a carbohydrate. Also, soluble fibres can also slow down transit time which will make the slow down the release of glucose and prevent sudden blood sugar spikes.
- Weight management – As it can slow down transit time of the food you eat it can keep you feeling full for longer, which in turn can prevent overeating and excessive snacking
- Prevent constipation – By adding bulk to the stool it will promote regularity and helps to eliminates harmful compounds and pathogens which may have protective effects against cancer.
How much dietary fibre do you need?
These days unfortunately, most people don’t eat enough fibre. Each country has different recommendations for fibre intake, but aiming to eat around 25-35 grams of dietary fibre a day is a good target to try and reach!
Dietary fibre are found in plant based foods such as fruit, berries, root vegetables, potatoes, leafy greens, whole grains (think whole spelt, whole oats, barley) and pulses and beans, so essentially by eating more fruit and veg, more whole grains (and less refined flour, cakes, biscuits etc )
How to increase fibre intake
Just try and squeeze in vegetables whenever possible, snack on fruit and nuts and use whole grains when possible and upping your dietary fibre intake should not be impossible!
- Eat more vegetables!
- Snack on fruit, berries and nuts
- Eat whole grains and minimise refined grains
- Increase your intake of pulses and beans
- Eat the skin on fruit, vegetables and potatoes
Examples of fibre rich meals
- 1 portion of porridge (oatmeal) (5 grams) + 1 pear (5 grams) = 10 grams
- This lentil and cabbage stir fry has over 10 grams of fibre per portion!
- This raspberry ice cream provided you with over 10 grams of fibre per portion!!!
- And this sweet potato rosti has around 12 grams of fibre per portion!
- A portion of this lentil bolognese with courgetti (zoodles) brings close to 12 gram of fibre!
Most foods rich in fibre are generally very nutritious as they’re rich in vitamins, minerals and antioxidants, so we should eat more of them anyway!
Psst! One downside to eating dietary fibre is that it can increase flatulence, as when bacterias are feasting on the fibres, they produce carbon dioxide as a result which can, quite bluntly said make you fart. If you’re not used to eating fibre rich foods, take it easy and up your fibre intake gradually when you start to prevent any discomfort and drink plenty of fluids. Also, if you’re suffering from IBS, IBD or any gastrointestinal disease, always consult with a nutritionist or dietitian before you start eating more fibre!