Dietary fibre is recognised as a valuable part of our diet with benefits to our health, however, most people worldwide are consuming less fibre than recommended. So what exactly is fibre? Where can we find it? And how can we ensure we are getting enough in our diet? 

What is dietary fibre?

Dietary fibre is not a specific food but rather a group of carbohydrates naturally found in plants - the edible part of plants. Unlike other carbohydrates, dietary fibre cannot be fully digested in our gut and is either completely or partially broken down by bacteria in our large intestine, helping our bowels function efficiently.

Dietary fibre is found in foods that come from plants, fruits, vegetables, whole grains, beans and pulses.

What are the benefits of fibre?

First and foremost fibre helps keep our digestive system healthy and normalises bowel movement, by bulking up and softening our stools by retaining water, which makes them easier and faster to pass, and prevents constipation.

On top of that, eating a diet that is high in fibre can help: 

• Feel fuller for longer - fibre-rich foods tend to be nutrient-dense and lower in calories which helps us feel fuller for longer - by slowing down digestion - and in turn, helps us maintain a healthy weight.

• Maintain good oral health - foods rich in fibre require longer chewing, which stimulates our saliva production and cleanses our teeth.

• Improve gut health - fibre can help increase the amount and diversity of gut microbiota - the good bacteria in our gut - by promoting an environment that is favourable to them. Our gut microbiota can ferment fibre and produce short-chain fatty acids which provide energy to our gut, help our immune system, and provide other health benefits such as the gut-brain axis - interactions between our intestines and our brain - which plays a role in mental health.

• Reduce the risk of disease - a high fibre diet has been shown to reduce the risk of heart disease - cardiovascular disease and coronary heart disease - , type 2 diabetes, and some cancers - bowel cancer and pancreatic cancer. This is because fibre and the short-chain fatty acids produced by our gut microbiota slow down the absorption of carbohydrates and lipids such as cholesterol, effectively balancing our blood sugar and lowering our blood cholesterol.

Other important nutrients such as vitamins, minerals and bioactive plant compounds are found in fibre-rich foods adding to the health benefits of a diet high in fibre.

How much fibre?

Most countries recommend for adults aged 17 years and over to consume 25-35g of fibre a day:

• 25-32g a day for women

• 30-35g a day for men

A fibre intake of 25g per day will keep our bowels functioning properly, whereas more than 25g per day helps reduce the risk of cardiovascular disease, type 2 diabetes and improve weight management.

Where to get fibre from?

Dietary fibre is found in plant-based foods including:

• Fruits - pears, strawberries, raspberries, figs, apples with skin, oranges, and dried fruits.

• Vegetables - peas, broccoli, carrots, corn, green beans, peppers and potatoes with skin.

• Nuts & seeds - almonds, chia seeds, pistachios, sunflower seeds, peanuts, and sesame.

• Pulses - lentils, chickpeas, beans, and split peas.

• Grains - oats, quinoa, buckwheat, wholewheat or bran cereals, wholewheat pasta, bread and rice.

When you read food labels, check for the grams of fibre per serving or per 100g:

• Source of fibre - at least 3g of fibre per 100g

• High in fibre - at least 6g of fibre per 100g

Tips to include more fibre in our diet

With all the health benefits fibre has to offer, there are many ways we can increase our fibre intake. It is important to get fibre from a variety of sources, the key is diversity.

Here are a few ways we can add more fibre to our meals everyday:

1. Choose a high fibre breakfast - opt for a higher-fibre breakfast cereal, wholemeal bread or porridge oats. Also add chia seeds or fruits to oats, smoothies or yoghurts.

2. Aim to meet 5-a-day (or more) of fruit and vegetables - keep frozen fruit and vegetables so you are never without and always ready to add them to dishes (e.g. pasta sauces, curries, risotto, chillies) or blend into a smoothie. Frozen fruit and vegetables have the same nutrients as fresh, are convenient and have a longer shelf life.

3. Keep the skin on - keeping the skin on fruit, vegetables and potatoes increases our fibre intake - and saves time not having to peel. Make sure to wash them carefully.

4. Cook with wholegrain - go for wholewheat pasta, quinoa, brown rice or buckwheat as part of meals.

5. Add beans and pulses to meals - add beans, lentils, chickpeas to any salads, curries, bolognese and stews or as a meat alternative.

6. Choose fibre-rich foods for snacks - choose fruit, nuts, seeds or even plain popcorn to snack on between meals.

When increasing our fibre intake we need to ensure we build up our intake slowly and drink plenty of fluids to avoid gastrointestinal symptoms - bloating and gas - and allow the fibre to do its job properly.

What’s the take-home?

1. ​​Dietary fibre has a lot of health benefits ranging from normalising our bowel movements and improving our gut health to reducing the risk of diseases such as cardiovascular diseases, type 2 diabetes and some cancers.

2. There are many sources of dietary fibre - fruit, vegetables, whole grains, beans and pulses - and many ways to incorporate more fibre in our meals. The key is diversity and colour.

3. A gradual increase of fibre in our diets, combined with plenty of fluids is the best way to avoid bloating and gas, and ensure our gut is adjusting to the higher intake.

Check out these other Nutrition & Lifestyle posts…

References

1. European Commission. Health Promotion and Disease Prevention Knowledge Gateway. Dietary Fibre | Knowledge for policy. 2019. Retrieved February 4, 2022, from https://knowledge4policy.ec.europa.eu/health-promotion-knowledge-gateway/dietary-fibre_en 

2. European Food Safety Authority. Scientific opinion on dietary reference values for carbohydrates and dietary fibre. EFSA Journal. 2010; 8(3). https://doi.org/10.2903/j.efsa.2010.1462 

3. Stephen AM, Champ M, Cloran SJ, Fleith M, van Lieshout L, Mejborn H, Burley VJ. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health. Nutrition Research Reviews. 2017, 1–42. doi:10.1017/s095442241700004x 

4. Barber TM, Kabisch S, Pfeiffer AFH, Weickert MO. The Health Benefits of Dietary Fibre. Nutrients. 2020;12(10):3209. Published 2020 Oct 21. doi:10.3390/nu12103209

5. Shortt C, Hasselwander O, Meynier A, Nauta A, Fernández EN, Putz P, Rowland I, Swann J, Türk J, Vermeiren J, Antoine J-M. Systematic review of the effects of the intestinal microbiota on selected nutrients and non-nutrients. European Journal of Nutrition. 2018, 57(1):25-49. doi:10.1007/s00394-017-1546-4 

6. European Comission. Food Safety - Nutrition Claims. Retrieved February 4, 2022, fromhttps://ec.europa.eu/food/safety/labelling-and-nutrition/nutrition-and-health-claims/nutrition-claims_en