Dietary fibre: an essential component of a balanced diet

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A balanced diet is vital for health and well-being. What this means is consuming a variety of foods in the right amounts to provide the body with all the nutrients it needs – carbohydrates, proteins, fats, vitamins, and minerals. Another very important component of a balanced diet is fibre, which is unfortunately often neglected.

Fibre is a type of carbohydrate that the human body is unable to digest. But even though we do not digest fibre, it plays a key role in maintaining digestive health, and indeed the health of the body as a whole. Fibre is found in a wide variety of foods, including fruit, vegetables, wholegrain cereals, and legumes.

There are two main types of fibre:

. Soluble fibre: soluble in water, it forms a gel-like substance that slows down digestion and the absorption of sugar. It can be broken down by “good” bacteria.

. Insoluble fibre: not soluble in water, it increases the volume of the stool, making bowel movements easier.

Another, more helpful way of classifying fibre is into fermentable and non-fermentable, indicating whether or not it can be used by beneficial gut bacteria.

In brief, fibre is indigestible carbohydrate derived from plant-based foods. Most foods contain both soluble and insoluble fibre.

There is a growing body of evidence that consuming sufficient fibre can benefit digestion and reduce the risk of chronic non-communicable diseases. Many of these benefits are mediated by the intestinal microbiota – the millions of bacteria found in the digestive tract.

Although fibre is very important, most people do not consume enough of it in their diet.

Ensuring the recommended daily fibre intake is essential for health. While the European Food Safety Authority (EFSA) recommends at least 25 grams of fibre per day for adults, most of Europe’s population does not meet these recommendations. According to research, the average daily intake for adult men in Europe is 18 to 24 grams, and for women 16 to 20 grams (1).

Fibre feeds beneficial gut bacteria

The intestine contains between 500 and 1,000 different species of bacteria, which together make up about 38 trillion cells. These intestinal bacteria are also called the gut microflora or gut microbiota (2,3). The relationship between the “good” bacteria and the body is one of mutual benefit.

We provide nourishment, shelter, and a safe environment for the bacteria, and in return they carry out tasks that the human body is unable to do on its own.

Of the many types of bacteria, some are key to various aspects of health, including weight management, blood sugar level regulation, immune system function, and even brain function.

But what does this have to do with fibre?

Like any other organism, bacteria must feed to obtain the energy they need to survive and function. The problem is that most of the carbohydrates, proteins, and fats are absorbed into the bloodstream before they reach the large intestine, leaving little for the gut microbiota. This is where fibre comes in. Since human cells do not have the enzymes to digest fibre, it enters the large intestine relatively intact.

In contrast, intestinal bacteria are equipped with enzymes to digest many types of fibre.

This is the main reason why fibre is essential for health. It is food for the beneficial gut bacteria and acts as a prebiotic. In this way, it stimulates the growth of “good” gut bacteria, which in turn can have a number of positive health effects (4).

The role of fibre in digestive health

Fibre has many positive effects on the digestive tract:

. Regulation of digestion: fibre increases stool volume and facilitates bowel movements, preventing constipation (5).

. Maintaining a healthy gut microflora: fibre is nourishment for beneficial gut bacteria, which are vital for the health of the digestive system and the body as a whole.

. Reducing the risk of colon cancer: fibre shortens the time it takes food to pass through the gut, reducing the exposure of the intestinal mucosa to carcinogens (6).

Role of fibre in overall health

In addition to the digestive tract, fibre is also important for health in general:

. Blood sugar regulation: soluble fibre slows down the absorption of sugar, preventing a sudden spike in blood sugar levels after a meal (7).

. Reduction of the risk of cardiovascular disease: fibre lowers blood cholesterol levels and thus reduces the risk of heart disease and stroke (8).

. Weight control: fibre provides a feeling of satiety, which helps to reduce calorie intake and makes it easier to maintain a healthy weight (9).

Conclusion:

Fibre is an essential part of a healthy diet. It has many positive effects on our health, from improving digestion and regulating blood sugar levels to reducing the risk of chronic diseases.

Although it is often overlooked, fibre plays a key role in maintaining health and preventing disease. It is therefore important to ensure adequate fibre intake by eating a varied diet rich in fruit, vegetables, wholegrain cereals, and legumes.

Including fibre in your day-to-day diet can significantly improve your quality of life and help you stay healthy.

Sources:

Stephen AM, Champ MM-J, Cloran SJ, et al. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health. Nutrition Research Reviews. 2017;30(2):149-190. doi:10.1017/S095442241700004X
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Martin O. Weickert, Andreas F.H. Pfeiffer. Metabolic Effects of Dietary Fiber Consumption and Prevention of Diabetes. The Journal of Nutrition, Volume 138, Issue 3, 2008, Pages 439-442, ISSN 0022-3166, https://doi.org/10.1093/jn/138.3.439. https://www.sciencedirect.com/science/article/pii/S0022316622095670?via%3Dihub
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