At first glance, the term "dietary fibre" may sound like something that burdens our bodies. But don't let the term mislead you. The truth is that fibre is extremely important for healthy digestion and elimination.
What is dietary fibre
Fibre is a special type of carbohydrate. More precisely, they are complex, (largely) indigestible carbohydrates that occur naturally in plant cells. This is why they are also known as fibres or plant fibres. Dietary fibre fulfils a variety of health-promoting functions in the body and is therefore an essential part of a healthy, balanced diet.
Dietary fibre: soluble and insoluble
A distinction is made between soluble and insoluble dietary fibre. This distinction is based on the solubility in water, which influences the properties and functions of the respective dietary fibres.
Pectins, inulin, plant mucilage and plant gums are soluble dietary fibres. They are also known as swelling agents as they store large amounts of water and swell in the intestine. This creates gel-like compounds that are largely broken down in the large intestine. Soluble fibre ensures regular bowel movements and excretion of toxins. Some soluble fibres are also prebiotics. This means that they serve as "food" for beneficial intestinal bacteria and thus contribute to a healthy intestinal flora.
The insoluble fibres include cellulose and its accompanying substance, hemicellulose. These fibres, also known as fillers, bind significantly less water and are hardly broken down by intestinal bacteria. As a result, they ensure a long-lasting feeling of satiety and stimulate intestinal activity, which in turn promotes digestion and elimination.1
Table: Soluble and insoluble dietary fibres
Soluble dietary fibre: Insoluble dietary fibre
Pectins: Cellulose
Inulin: Hemicellulose
Plant mucilage and plant gums
Foods rich in fibre: where to find fibre
Fibre is an indigestible, long-chain carbohydrate that is a component of plant cells. Accordingly, they are naturally found in all plant-based foods - above all in
- fruit
- vegetables
- wholemealcereal products
- legumes
- seeds and
- nuts
Fibre is a structural building block in plants and is usually found in the shells or edge layers. marginal layers. Therefore, wholemeal cereal products should be preferred and fruit and vegetables should not be peeled if possible (e.g. apples, cucumbers, etc.). As a general rule, whole, plant-based foods in as natural a form as possible are the best sources of fibre.
Most plant-based foods contain both soluble and insoluble fibre. However, the proportions can vary. Below is an overview of where you can find which fibre:
Table: Foods rich in fibre
Soluble fibre: Foods
Pectins: Unripe fruit, seeds & peel of apples, quinces & berries
Inulin: Chicory, Jerusalem artichokes, garlic, artichokes
Plant mucilage and plant gums: Algae, juices of tropical plants (e.g. acacia)
.e.g. acacia)Insoluble fibre: Food
Cellulose: Fruit, vegetables, pulses, wholegrain cereals
Hemicellulose: Fruit, vegetables, pulses, wholegrain cereals
Foods rich in fibre: gluten-free sources of fibre
Fibre is often associated with cereals. This is true, as the outer layers of cereals contain both soluble and insoluble fibre. Nevertheless, there is also a variety of gluten-free high-fibre foods. Nothing stands in the way of a high-fibre diet despite coeliac disease, wheat intolerance or other reasons for not eating gluten. Here are some examples of gluten-free foods with a high fibre content:
List - high-fibre, gluten-free foods
- Fruit
- Vegetables
- Wholemeal rice
- Quinoa
- Amaranth
- Millet
- Buckwheat
- Gluten-free rolled oats
- Seeds
- Nuts
In addition to the solid foods mentioned, liquid drinking meals play an increasingly important role in providing important nutrients. Our Saturo drinks, a form of liquid food, contain a balanced mix of soluble and insoluble fibre. These meal replacement shakes are particularly useful for people who have little time and still value a healthy diet.
Why do we need dietary fibre? Effects and functions
Fibre plays an important role in our metabolism and our overall state of health. The consumption of fibre has an immediate positive effect on digestion in particular. In the long term, however, a high-fibre diet has a number of other health-promoting effects, which are explained in more detail below.
Fibre stimulates digestion
Soluble fibre ensures regular bowel movements and increased stool volume. This shortens the so-called "intestinal transit time". This means that with a high-fibre diet, our food remains in our digestive tract for a shorter time, is processed more quickly and excreted again. This prevents constipation and the resulting health problems such as diaphragmatic hernia, varicose veins and haemorrhoids. Soluble fibre also binds toxins, such as heavy metals or excess cholesterol, and ensures their excretion. In addition, prebiotic fibres serve as food for beneficial intestinal bacteria and thus have a positive influence on our intestinal flora.2
Insoluble fibres are hardly broken down by the intestinal bacteria. They therefore pass through our intestinal tract largely undigested and ensure a lasting feeling of satiety. They also stimulate intestinal activity and thus promote our digestion and excretion. As insoluble fibre is not digested, it is completely excreted. This has a positive effect on the quantity and consistency of our stools.[<[sup>3
Functions of soluble dietary fibre: Digestion & elimination
Soluble fibre ensures
- regular bowel movements
- shortened "intestinal transit time"
- binding & elimination of toxins in the intestine
- increased formation of positive intestinal bacteria
Functions of insoluble fibre: Bowel & satiety
Insoluble fibre provides
- persistent feeling of satiety
- improved bowel function & elimination
- improved stool quantity &texture
Fibre prevents bowel cancer
Due to the shortened intestinal transit time with a high-fibre diet, deposits and inflammation in the digestive tract are minimised. Fibre can therefore help to prevent bowel cancer and other bowel diseases.4
Fibre reduces the risk of breast cancer
Several studies have also linked a high-fibre diet with a lower risk of developing breast cancer. For every 20 g of fibre intake per day, a reduced risk of breast cancer of up to 15% was found.5
Fibre strengthens the immune system
The connection between our immune system and our digestion has now been scientifically proven several times.[<[sup>678 A healthy intestinal flora and regular elimination contribute to a strong immune system. Fibre is therefore also essential for our immune defence.[<[sup>9
Fibre against lifestyle diseases
In addition to the benefits mentioned, a sufficient fibre intake also reduces the risk of type 2 diabetes, heart disease, strokes and obesity.10 One of the reasons for this is that fibre helps to regulate blood sugar and cholesterol levels. This in turn leads to a reduction in the diseases mentioned. A balanced, high-fibre diet and a healthy lifestyle can largely prevent these lifestyle diseases.
Fibre increases life expectancy
In general, it has been found that people who eat a high-fibre diet live longer. Due to its positive influence on digestion and the immune system, its general health-promoting effect and its preventive properties, fibre is a natural elixir of life. A diet rich in fibre not only increases life expectancy, but also ensures more healthy years of life.11
Fibre-rich diet: what you need to know
Are you convinced that you should include more fibre in your diet, but aren't sure what to look out for? No problem! We explain everything you need to know about a high-fibre diet.
How much fibre should you eat per day?
First of all, of course, there is the question of the recommended daily intake of fibre. The general recommendation is a minimum of 30 g of fibre per day.12There is no upper limit - there is de facto no such thing as an overdose of fibre. Diets that are specifically used to cure diseases such as bowel cancer, type 2 diabetes or heart problems even include 60 - 85 g of fibre per day. 13
Increase fibre gradually
As with any change, we recommend not going from zero to one hundred from one day to the next. This can overload your digestive system and lead to abdominal pain and bloating. Increase the amount of fibre in your diet gradually so that your body can get used to it. For example, start by switching all cereal products (bread, pasta, etc.) to whole grains.
Chew high-fibre foods well
It is also particularly important to chew well when eating a high-fibre diet. Fibre is not or only partially digested in the intestine. It is therefore all the more important to break it down in the mouth and lay the foundation for ensuring that your digestive tract is not overloaded.
Drink enough when eating a high-fibre diet
As fibre binds water in the intestine, you should also increase your fluid intake along with the amount of fibre in your diet. Drink an extra glass of water around 15 minutes before eating to prepare your digestive system for the fibre intake
.Low-fibre diet: preferably without fibre in exceptional cases
For healthy people, fibre is an essential part of a balanced diet and has a variety of health-promoting effects. Nevertheless, there are also situations in which fibre should be temporarily avoided.
When fibre should be avoided
As already mentioned, fibre stimulates intestinal activity, digestion and elimination. This is generally positive, but can lead to additional stress in the case of acute illnesses or inflammation of the digestive tract. You should therefore avoid fibre in the following cases in the short term:
- acute gastrointestinal inflammation
- before a colonoscopy
- after certain operations
It is important to note that you should only temporarily switch to a low-fibre diet. Once the inflammation has calmed down or the operation is over, fibre is once again beneficial to ensure your long-term health and a functioning digestive system. Only in acute cases, when your body is overloaded, should you eat a low-fibre diet in the short term.1415
You should focus primarily on a light diet. Here are a few examples of a low-fibre, light diet:
List of low-fibre foods (light diet)
- Vegetables with a high water content, e.g. courgettes, tomatoes, tomatoes, tomatoes and vegetables. Courgettes, tomatoes, leaf lettuce, cucumbers (peeled, without seeds)
- Potatoes (cooked, peeled)
- White rice
- Applesauce (without skin)16
Low-fibre diet: Not recommended in the long term
With the exceptions just mentioned, a low-fibre diet is not recommended in the long term and for healthy people. The main reason for this is that our body deposits toxins (e.g. lead, mercury or excess cholesterol) in the digestive system to be excreted from there with the help of fibre. However, if we do not consume enough fibre, these toxins remain in the body and can lead to a variety of problems. This is one of the reasons why an insufficient intake of fibre is associated with an increased risk of cancer of the digestive tract.
In addition, a low-fibre diet is associated with constipation, digestive problems and a weakened immune system. A large number of civilisation diseases (e.g. obesity, heart attacks, strokes, type 2 diabetes) are also caused by a lack of fibre.17
Low-fibre diet: be careful with the following low-fibre foods
Fibre is naturally found mainly in plant-based foods. This means that animal products, especially fish, meat and eggs, are not sources of health-promoting fibre. Dairy products contain minimal amounts of fibre, but are still classified as low in fibre. These products should therefore be consumed in smaller quantities and in combination with wholesome, plant-based foods.
Heavily industrially processed products (junk food, sweets, etc.) and extracted flour (= white flour; consists only of the inner part of the grain - the fibre-rich outer layers are removed before grinding) are also low in fibre and provide hardly any other valuable nutrients. You should therefore avoid these products as much as possible and only enjoy them in exceptional cases.[<[sup>18
List of low-fibre foods (not suitable as a light diet)
- Meat
- Fish
- Eggs
- Dairy products
- Sweets
- White flour desserts
- Soft drinks
- Junk food
Conclusion: Dietary fibre promotes digestion and prevents diseases
In addition to an optimal ratio of protein, fats and carbohydrates and a high density of micronutrients, a balanced diet is characterised by one thing in particular: at least 30 g of fibre every day.
Foods rich in fibre should make up the majority of your diet. As fibre is a component of plant cells, it is also known as roughage and is found almost exclusively in plant foods. We have summarised the most important sources of fibre for you here:
List of high-fibre foods
- Fruit
- Vegetables
- Whole grains
- "Pseudograins" (such as millet, quinoa and buckwheat)
- Pulses
- Nuts
- Seeds
A variety of bodily processes are improved by a high-fibre diet: Bowel movements, digestion, building positive gut flora and eliminating toxins are the most important of these. Fibre is also said to have health-promoting and preventative effects.
Health-promoting and disease-preventing effects of dietary fibre
- Fibre prevents bowel cancer
- Fibre reduces the risk of breast cancer
- Fibre strengthens the immune system
- Fibre prevents lifestyle diseases such as type 2 diabetes, heart disease, strokes and obesity
- Fibre increases life expectancy
A high-fibre diet therefore pays off. It is important that you gradually increase the amount of fibre in your diet, chew well and drink plenty of fluids
FAQs: The most important facts about fibre summarised
What is dietary fibre?
Fibre is an indigestible, complex carbohydrate. They are a natural component of plant cells and an essential part of a healthy, balanced diet.
What is the difference between soluble and insoluble fibre?
Soluble dietary fibres are soluble in water and therefore (at least partially) digestible. They are largely broken down by the intestinal bacteria and thus serve as "food" for positive intestinal bacteria.Insoluble dietary fibres, on the other hand, arecompletely indigestible. They act as a filler in the gut, ensure a lasting feeling of fullness and stimulate digestion.
Why do we need fibre?
Fibre ensures good digestion, promotes intestinal activity and elimination and has a preventive effect on the following diseases:
- Breast cancer
- Intestinal cancer
- Heart disease
- Stroke
- Diabetes
- Obesity
How much fibre should you consume per day?
In order to benefit from the health-promoting effects of fibre, you should consume at least 30 g of fibre per day. You can cover your daily fibre requirement, for example:
100 g wholemeal bread (approx. 2 slices)
+ 300 g fruit (approx. 3 pieces)
+ 300 g vegetables (approx. 3 fist-sized portions)
+ 250 g potatoes (approx. 4 pcs)
+ 60 g muesli mix (approx. 4 tbsp)19
Is it possible to eat too much fibre?
Naturally not. However, caution is advised with high-fibre food supplements. If you have been on a low-fibre diet for a long time, a sudden, extreme increase can initially lead to digestive problems. To avoid this, you should gradually increase thefibre content in your diet. This will allow your digestive system to slowly get used to the change. As fibre binds water, you should also make sure youhave a sufficient fluid intake.
#ERROR!
Fibre is contained in all plant-based foods. Particularly rich in fibre are:
- Fruit
- Vegetables
- Whole grains
- "Pseudograins" (such as millet, quinoa or buckwheat)
- Pulses
- Nuts
- Seeds
Are high-fibre foods healthy?
Yes, fibre is naturally found in wholesome, plant-based foods. These also contain a variety of other health-promoting substances such asvitamins, minerals and phytochemicals. These foods therefore form the basis of a balanced diet.
What are low-fibre foods?
Animal products, highly processed foods and junk food contain little or no fibre. Low-fibre foods include:
- Meat
- Fish
- Eggs
- Dairy products
- Sweets
- Flour-based desserts
- Soft drinks
- Junk food
What is the best fibre for the gut?
The best sources of fibre for healthy intestinal flora include resistant starch from wholegrain products, green bananas or cooked potatoes, pectins from apples, carrots or citrus fruits, beta-glucans from oats and barley and inulin from chicory, leeks or asparagus. Fermentable oligosaccharides from pulses and linseed as well as cellulose and lignin from wholemeal products, nuts and seeds are also considered to be particularly beneficial for the gut. It is best to eat a varied mix of different fibre sources to optimally support the gut microbiome.
You might also be interested in this
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