Dietary fibre refers to the parts of plant-based foods that we cannot digest, sometimes referred to as ‘roughage’ or ‘bulk’. Fibre can be found in foods that come from plants – think starchy carbohydrates, fruits, vegetables and lentils. Animal products, such as meat, fish, cheese and fats, do not contain any fibre. Research shows that most adults are not eating enough fibre each day; the average adult consumes 20g per day, but recommended guidelines are 30g a day for both adult men and women.
Fibre is probably best known for its role in regulating bowel movements, but what other effects does it have on our bodies? Senior physiologist Stephanie and associate nutritionist (ANutr) Gina explore the types of fibre and all the reasons to increase your intake below!
There are different types of fibre that all have a role to play in keeping us healthy. It is important to consider where you are getting them from within your diet, or what you can do to increase the amount you consume.
Insoluble fibre is what we typically think of as ‘fibre’; it helps keep everything moving through our gut and adds bulk to stools. Without this type of fibre, we can have difficulties with bowel movement, commonly constipation and diarrhoea. Insoluble fibre is found in wheat bran, whole grains and vegetables.
Soluble fibre dissolves in water to form a gel in the gut; it helps to keep stools soft and has also been linked to helping lower cholesterol levels. It also plays an import role in helping our bodies absorb nutrients from foods, making sure that those minerals and vitamins aren’t going to waste! Soluble fibre is found in foods such as nuts, seeds, beans, lentils and some fruits and vegetables.
Resistant fibre cannot be broken down by the small intestine, but ferments in the large intestine to form fatty acids that keep the gut healthy.
Greater dietary fibre intake isn’t just advised for healthy transport of food through the gut, it is also associated with lower risk of cardiovascular disease, coronary heart disease, diabetes and some types of cancer.
As the body cannot break down most fibre, it passes straight through the intestines to the bowels where it is then fermented by bacteria. As a result, lots of gases are produced and these are what play an important role in our body. It therefore isn’t uncommon to experience mild bloating after increasing fibre in your diet, eating food rich in fibre or if you eat quickly.
Fibre can help to regulate blood pressure and cholesterol, making it a possible key to better heart health. The process fibre goes through in the body requires bile acids that are partly created by cholesterol, meaning the more fibre we eat the more cholesterol the body uses to process it, helping to lower our bad (LDL) cholesterol levels.
Fibre has also been linked to regulating blood sugar; research has shown that lower blood sugar levels are found in those with high fibre consumption. The impact has been associated mainly to soluble fibre sources and its ability to slow the absorption of sugar to the blood stream.
Research, although mixed, has also linked higher fibre consumption as a preventative factor in colorectal cancer; however, the National Cancer Institute has not found a reduction in risk.
New research also links fibre with increased life expectancy, reduction in food allergies and asthma.
Not only is fibre great for our health, the foods that contain fibre can be beneficial in other ways. Complex carbohydrates, such as wholegrain breads and pastas, oats and quinoa, are packed full of fibre and promote feelings of fulness, due to their slow release of energy. This can be great when looking to manage weight or improve our energy levels throughout the day.
Think about what higher fibre options you can build into your diet by incorporating our fibre champions below.
Looking at food labels?
If you are interested in understanding the best fibre-boosting value foods, take a look at nutritional information on packaging. For an item to be considered a source of fibre it needs to contain 3g of fibre per 100g. A high in fibre item has 6g of fibre per 100g.