Why is dietary fibre important?

Dietary fibre is found naturally in plant foods and forms an important part of a healthy, balanced diet. Unlike many other carbohydrates, fibre isn't completely digested in the small intestine and instead continues into the large intestine.

Different types of fibre have different properties and are found across foods including wholegrains, fruit, vegetables, beans, pulses, nuts and seeds. Eating a varied range of these foods can help you work towards the recommended daily fibre intake while providing other important nutrients as part of your diet.

What is Dietary Fibre?

Dietary fibre, often referred to as roughage, is found in the cell walls of plant-based foods. It's a type of carbohydrate that the body can't digest, meaning it passes through the digestive system relatively intact(1). Rather than being digested and absorbed like many other carbohydrates, fibre continues through the digestive tract, where different types of fibre have different properties and roles.

Soluble and Insoluble Fibre

Fibre is commonly divided into two main types: soluble and insoluble. Both have different properties and are found in a variety of plant-based foods.

Soluble fibre dissolves in water to form a gel-like substance and can help lower blood cholesterol and glucose levels. Sources of soluble fibre include oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium(6).

Insoluble fibre increases stool bulk and helps food pass more quickly through the stomach and intestines, supporting regular bowel movements. Sources include whole wheat flour, wheat bran, nuts, beans and vegetables such as cauliflower, green beans and potatoes(6).

Fibre as Part of a Healthy Diet

Fibre plays an important role in a healthy, balanced diet, with different types of fibre having different properties. It can increase the weight and size of stools while helping to soften them, which can help reduce constipation. Soluble fibre absorbs water and adds bulk, which may also help to firm loose stools(6).

High-fibre foods can also be more filling because they tend to be digested more slowly than lower-fibre foods. This may help you feel satisfied for longer and could support the management of overall food intake(5). Many naturally fibre-rich foods, including fruit, vegetables, wholegrains, beans, pulses, nuts and seeds, also provide a range of other nutrients.

Research has also explored the relationship between fibre intake and metabolic and cardiovascular health. Soluble fibre may slow glucose absorption and help improve blood glucose levels(9), while adequate fibre intake may contribute to heart health, including through its effects on low-density lipoprotein (LDL) cholesterol(10).

Looking at longer-term health outcomes, studies have found associations between higher fibre intake and a lower risk of cardiovascular disease, certain cancers and all-cause mortality(11). These findings support the importance of including a varied range of fibre-rich foods as part of a healthy, balanced diet.

Top Ten FAQs - Fibre

What is dietary fibre?

Dietary fibre is a type of carbohydrate found naturally in plant foods that isn't completely digested by the body. Instead, it passes through the digestive system relatively intact(1).

How much fibre should I eat per day?

The NHS recommends that adults aim for around 30g of fibre per day. However, average fibre intake in the UK is lower than the recommended amount, so many adults may benefit from including more fibre-rich foods in their diet(2).

What is the difference between soluble and insoluble fibre?

Soluble fibre dissolves in water and can form a gel-like substance, while insoluble fibre does not dissolve in water in the same way and helps food move through the digestive system(3).

Which foods are high in fibre?

Good sources of dietary fibre include fruit, vegetables, wholegrains, beans and other pulses, nuts and seeds(4).

What is fibremaxxing?

Fibremaxxing is a term that has become popular for deliberately making fibre-rich foods a greater part of your diet. Rather than simply trying to consume as much fibre as possible, a balanced approach means working towards the recommended daily intake using a varied range of fibre sources.

Can increasing fibre cause bloating?

Increasing fibre intake too quickly can cause temporary digestive symptoms such as bloating, gas or diarrhoea. It's best to increase your intake gradually and drink plenty of fluids while your digestive system adjusts(6).

How can I add more fibre to my diet?

Small changes throughout the day can help increase your fibre intake. Try choosing wholegrain bread, pasta or cereals, eating more fruit and vegetables, and adding beans, lentils, chickpeas, nuts or seeds to meals and snacks.

Why is it important to drink water when increasing fibre?

Adequate fluid intake is important when increasing the amount of fibre in your diet. Fibre absorbs water as it moves through the digestive system, so increasing fibre gradually and drinking plenty of fluids can help your digestive system adjust(6).

Should I increase my fibre intake gradually?

Yes. If your current diet is relatively low in fibre, increasing your intake gradually gives your digestive system time to adjust and may help reduce temporary symptoms such as bloating, gas or diarrhoea(6).

Can fibre supplements help increase my fibre intake?

Fibre-rich foods should form an important part of a varied, balanced diet because they also provide a range of other nutrients. Fibre supplements can provide an additional source of fibre for people looking to increase their daily intake(8).

How Much Fibre Do You Need?

The NHS recommends that adults aim for around 30g of fibre per day. However, the average UK adult consumes only around 18g per day, meaning many people may not be reaching the recommended daily amount(2).

Incorporating Fibre into Your Diet

Increasing your fibre intake doesn't have to mean completely changing the way you eat. Simple changes throughout the day can help you include a greater variety of fibre-rich foods and gradually work towards the recommended daily intake.

At breakfast, choosing wholegrain cereals or porridge can provide more fibre, while swapping white bread, pasta and rice for wholegrain varieties is another straightforward way to increase your intake. When baking, whole-wheat flour can be used in place of some or all of the white flour, with nuts and seeds providing another way to add fibre.

Fruit and vegetables can make useful fibre-rich snacks, while nuts, nut butters and hummus can provide additional fibre alongside other nutrients. Beans, lentils and chickpeas can also be incorporated into meals such as soups, stews, curries and salads, helping to increase both the amount and variety of fibre in your diet.

Alternative ingredients such as chickpea or almond flour can also be used in some recipes to increase fibre intake. Making several small changes across your meals and snacks can be a more manageable approach than trying to dramatically increase your fibre intake all at once.

Increasing Fibre Gradually

If you're increasing the amount of fibre in your diet, it's best to do so gradually. A sudden increase can cause temporary digestive symptoms such as bloating, gas or diarrhoea. Drinking plenty of fluids is also important, as fibre absorbs water as it moves through the digestive system(6).

Giving your body time to adjust can make increasing your fibre intake more comfortable and easier to maintain over the longer term.

What Is Fibremaxxing?

Fibremaxxing is a term that has become popular on social media for deliberately increasing the amount of fibre in your diet and making fibre-rich foods a greater priority in everyday meals. While the name is relatively new, the principle behind it isn't: UK guidance already recommends that adults aim for around 30g of fibre per day as part of a healthy, balanced diet.

Rather than focusing on a single food or type of fibre, a balanced approach to fibremaxxing means including a variety of fibre sources throughout the day. Wholegrains, fruit, vegetables, beans, pulses, nuts and seeds can all contribute towards your daily intake, while also providing different types of dietary fibre.

The aim shouldn't be to consume as much fibre as possible. If your current intake is relatively low, suddenly increasing it significantly may lead to bloating, gas or changes in bowel habits. Increasing fibre gradually and drinking plenty of fluids gives your digestive system time to adjust(6).

For people who find it difficult to reach their fibre target through food alone, a fibre supplement can provide an additional source of dietary fibre. Supplements should complement rather than replace a varied, balanced diet.

Fibremaxxing with a varied diet

A practical approach doesn't require every meal to be exceptionally high in fibre. Instead, fibre can be spread throughout the day. Choosing a wholegrain breakfast, including fruit or vegetables with meals, adding beans or pulses where appropriate and choosing nuts or seeds as part of snacks can all contribute towards your overall intake.

Looking at your diet as a whole can also help you include a broader range of fibre sources rather than relying heavily on one ingredient. As we've explored above, different foods contain different types of fibre, so variety remains important.

The Bigger Picture

Fibre is an important part of a healthy, balanced diet, and variety matters. Wholegrains, fruit, vegetables, beans, pulses, nuts and seeds can all contribute different types and amounts of fibre to your daily intake.

For many people, small changes across meals and snacks can make it easier to work towards the recommended 30g of fibre per day. Where diet alone doesn't provide enough, a fibre supplement can offer a convenient way to increase daily intake alongside a varied, balanced diet.

If you're looking for an easy way to add more fibre to your routine, Lily & Loaf Super Fibre provides 11.7g of fibre per daily serving from seven different fibre sources, including apple fibre, psyllium husk, FOS, inulin, guar gum, oat bran and acacia gum.

Fibre: A Comprehensive Guide

References

  1. Barber TM, Kabisch S, Pfeiffer AFH, Weickert MO. The Health Benefits of Dietary Fibre. Nutrients. 2020;12(10):3209. doi:10.3390/nu12103209
  2. National Health Service. How to get more fibre into your diet.
  3. Guan ZW, Yu EZ, Feng Q. Soluble Dietary Fiber, One of the Most Important Nutrients for the Gut Microbiota. Molecules. 2021;26(22):6802. doi:10.3390/molecules26226802
  4. Dietary Guidelines for Americans. Food Sources of Dietary Fiber.
  5. Kelly RK, Calhoun J, Hanus A, Payne-Foster P, Stout R, Sherman BW. Increased dietary fiber is associated with weight loss among Full Plate Living program participants. Front Nutr. 2023;10:1110748. doi:10.3389/fnut.2023.1110748
  6. Ioniță-Mîndrican CB, Ziani K, Mititelu M, et al. Therapeutic Benefits and Dietary Restrictions of Fiber Intake: A State of the Art Review. Nutrients. 2022;14(13):2641. doi:10.3390/nu14132641
  7. Better Health Channel. Dietary fibre.
  8. McRorie JW Jr. Evidence-Based Approach to Fiber Supplements and Clinically Meaningful Health Benefits, Part 1: What to Look for and How to Recommend an Effective Fiber Therapy. Nutr Today. 2015;50(2):82-89. doi:10.1097/NT.0000000000000082
  9. McRae MP. Dietary Fiber Intake and Type 2 Diabetes Mellitus: An Umbrella Review of Meta-analyses. J Chiropr Med. 2018;17(1):44-53. doi:10.1016/j.jcm.2017.11.002
  10. McRae MP. Dietary Fiber Is Beneficial for the Prevention of Cardiovascular Disease: An Umbrella Review of Meta-analyses. J Chiropr Med. 2017;16(4):289-299. doi:10.1016/j.jcm.2017.05.005
  11. Xu X, Zhang J, Zhang Y, Qi H, Wang P. Associations between dietary fiber intake and mortality from all causes, cardiovascular disease and cancer: a prospective study. J Transl Med. 2022;20(1):344. doi:10.1186/s12967-022-03558-6

This guide has been fact-checked by Brittany Lubeck, a Registered Dietitian Nutritionist with expertise in Clinical Nutrition. The information provided is based on current scientific research and regulatory guidelines.