Table of contents
1 What is dietary fiber?
Dietary fiber: Soluble and insoluble Table: Soluble and insoluble dietary fibers
2 Fiber-rich foods: Where can you find fiber?
Table: High-fiber foods High-fiber foods: Gluten-free sources of fiber
3 What do you need fiber for? Effects and functions
Dietary fiber stimulates digestion Dietary fiber prevents bowel cancer Dietary fiber reduces the risk of breast cancer Dietary fiber strengthens the immune system Dietary fiber against civilization diseases Dietary fiber increases life expectancy
4 High-fiber diet
How much fiber should you eat per day? Gradually increase your fiber intake Chew high-fiber foods well Drink enough when eating a high-fiber diet
5 Low fiber diet
When fiber should be avoided Low-fiber diet: Not recommended in the long term Low-fiber diet: Be careful with the following low-fiber foods
6 Conclusion

At first glance, the term "fiber" may sound like something that puts a strain on our bodies. But don't let the term mislead you. The truth is that fiber is extremely important for healthy digestion and elimination.

What is dietary fiber?

Dietary fiber 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 fibers or plant fibers. Dietary fiber fulfills a variety of health-promoting functions in the body and is therefore an essential part of a healthy, balanced diet.

Dietary fiber: Soluble and insoluble

A distinction is made between soluble and insoluble dietary fibers. This distinction is based on the Solubility in waterwhich influences the properties and functions of the respective dietary fibers.

Pectins, inulin as well as plant mucilage and plant gums are soluble dietary fibers. They are also known as swelling agents as they store large amounts of water and swell up in the intestine. This creates gel-like compounds that are largely broken down in the large intestine. Soluble fiber ensures regular bowel movements and elimination of toxins. Some soluble fibers are also prebiotics. This means that they serve as "food" for beneficial intestinal bacteria and thus contribute to a healthy intestinal flora.

To the insoluble dietary fibers include cellulose and its accompanying substance, hemicellulose. These fibers, also known as fillers, bind considerably less water and are hardly broken down by intestinal bacteria. As a result, they ensure a long-lasting feeling of satiety and a stimulated intestinal activitywhich in turn promotes digestion and elimination.1

Table: Soluble and insoluble dietary fibers

Soluble dietary fiber Insoluble dietary fibers
Pectins Cellulose
inulin hemicellulose
Plant mucilage and plant gum

Fiber-rich foods: Where can you find fiber?

Dietary fibers are indigestible, long-chain carbohydrates that are components of plant cells. Accordingly, they are naturally found in all plant foods - especially in

  • fruit 
  • vegetables
  • Whole grain cereal products
  • legumes
  • seeds and 
  • nuts

Dietary fibers are structural building blocks in plants, mostly in the shells resp. edge layers concentrated. Therefore, whole grain cereal products should be preferred and fruit and vegetables should not be peeled if possible (e.g. apples, cucumbers, etc.). As a general rule: Wholesome, plant-based foods in as natural a form as possible are the best sources of fiber.

Most plant-based foods contain both soluble and insoluble fiber. However, the proportions can vary. Below is an overview of where you can find which fiber:

Table: High-fiber foods

Soluble dietary fiber Foods
Pectins Unripe fruit, seeds & peel of apples, quinces & berries
inulin Chicory, Jerusalem artichokes, garlic, artichokes
Plant mucilage and plant gum Algae, tropical plant juices (e.g. acacia)
Insoluble fiber Foods
Cellulose Fruit, vegetables, pulses, wholegrain cereals
Hemicellulose Fruit, vegetables, pulses, wholegrain cereals

High-fiber foods: Gluten-free sources of fiber

Dietary fiber is often associated with cereals. This is correct, as the outer layers of cereals contain both soluble and insoluble fiber. However, there is also a variety of gluten-free foods rich in fiber. Nothing stands in the way of a high-fiber diet despite coeliac disease, wheat intolerance or other reasons for not eating gluten. Here are some examples of gluten-free foods with a high fiber content:

List - high-fiber, gluten-free foods

  • Fruit
  • vegetables
  • Whole grain rice
  • Quinoa
  • Amaranth
  • Millet
  • Buckwheat
  • Gluten-free rolled oats
  • seeds
  • Nuts

In addition to the solid foods mentioned above, complete liquid meals are playing an increasingly important role in providing us with important nutrients. Our Saturo-drinks, a form of liquid foodcontain a balanced mixture of soluble and insoluble fiber. These meal replacement shakes are particularly useful for people who have little time and still attach importance to a healthy diet.

What do you need fiber for? Effects and functions

Dietary fiber plays an important role in our metabolism and our overall state of health. The consumption of dietary fiber has an immediate positive effect on digestion. In the long term, however, a high-fiber diet has a variety of other health-promoting effects, which are explained in more detail below.

Dietary fiber stimulates digestion

Soluble fiber ensures regular bowel movements and increased stool volume. This stimulates the so-called "intestinal transit time" is shortened. This means that with a high-fiber diet, our food remains in our digestive tract for a shorter time, is processed and excreted more quickly. This prevents constipation and the resulting health problems such as diaphragmatic hernia, varicose veins and hemorrhoids. In addition, soluble fiber binds toxinssuch as heavy metals or excess cholesterol and ensure that they are eliminated. elimination. In addition prebiotic fiber serve as food for beneficial intestinal bacteria and thus influence our intestinal flora positively2

Insoluble fiber is hardly broken down by the intestinal bacteria. Therefore, they pass through our intestinal tract largely undigested and ensure a persistent feeling of satiety. They also stimulate the intestinal activity and thus promote our digestion and elimination. As insoluble fiber is not digested, it is completely excreted. This has a positive effect on the quantity and consistency of our stools.3

Functions of soluble fiber: digestion & excretion

Soluble fiber ensures

  • regular bowel movements
  • Shortened "intestinal transit time"
  • Binding & excretion of toxins in the intestine 
  • Increased formation of positive intestinal bacteria

Functions of insoluble fiber: intestine & feeling of satiety

Insoluble fibers provide for

  • a lasting feeling of satiety
  • Improved intestinal activity & elimination
  • improved stool quantity & consistency

Dietary fiber prevents colon cancer

Due to the shortened intestinal transit time with a high-fiber diet minimizes deposits and inflammation in the digestive tract. Fibre can therefore help to prevent bowel cancer and other bowel diseases.4

Dietary fiber reduces the risk of breast cancer

Several studies have also linked a high-fiber 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

Dietary fiber strengthens the immune system

The connection between our immune system and our digestion has now been scientifically proven many times over.678 One healthy intestinal flora and regular elimination contribute to a strong immune system. system. Fibre is therefore also essential for our immune system.9

Dietary fiber against civilization diseases

In addition to the benefits mentioned above, a sufficient intake of fiber also reduces the risk of Type 2 diabetes, heart disease, strokes and obesity.10 One reason for this is that dietary fiber helps to regulate blood sugar and cholesterol levels. This in turn leads to a reduction in the diseases mentioned. A balanced, high-fiber diet and a healthy lifestyle can largely prevent these diseases of civilization.

Dietary fiber increases life expectancy

In general, it has been found that people who eat a high-fiber diet live longer. Due to its positive influence on digestion and the immune system, its general health-promoting effect and its preventive properties, dietary fiber is a natural elixir of life. A diet rich in fiber not only increases life expectancy, but also ensures more healthy years of life.11

High-fiber diet: what you need to know

Are you convinced that you should include more fiber in your diet, but you're not sure what to look out for? No problem! We explain everything you need to know about a high-fiber diet.

How much fiber should you eat per day?

First of all, of course, there is the question of the recommended daily intake of fiber. The general recommendation is Minimum of 30 g of fiber per day.12 There is no upper limit - in fact, there is no such thing as an overdose of fiber. Diets that are used specifically to cure diseases such as bowel cancer, type 2 diabetes or heart problems even provide for 60 - 85 g of fiber per day. 13

Gradually increase fiber content

As with any change, we also recommend not going from zero to one hundred from one day to the next when it comes to fiber. This can overload your digestive system and lead to abdominal pain and bloating. Increase the amount of fiber in your diet graduallyso that your body can get used to it. For example, start by switching all cereal products (bread, pasta, etc.) to whole grains.

Chew high-fiber foods well

It is also particularly important to eat a high-fiber diet, chew well to chew. Fiber is not or only partially digested in the intestine. This makes it all the more important to break it down in the mouth and lays the foundation for ensuring that your digestive tract is not overwhelmed.

Drink enough when eating a high-fiber diet

As fiber binds water in the intestine, you should also increase the amount of fiber in your diet together with your fluid intake increase your fluid intake. Drink an extra glass of water about 15 minutes before eating to prepare your digestive system for the fiber intake.

Low-fiber diet: In exceptional cases, preferably without fiber

For healthy people, fiber is an essential part of a balanced diet and has a variety of health-promoting effects. Nevertheless, there are also situations in which fiber should be temporarily avoided.

When fiber should be avoided

As already mentioned, dietary fiber stimulates intestinal activity, digestion and elimination. This is generally positive, but can in the case of acute illnesses or inflammation of the digestive tract lead to additional stress. You should therefore avoid dietary fiber in the short term in the following cases:

  • acute gastrointestinal inflammation
  • before a colonoscopy
  • after certain operations

It is important that you only temporarily switch to a low-fiber light diet. Once the inflammation has calmed down or the procedure is over, fiber is beneficial again 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 light food. Here are a few examples of low-fiber light diet:

List of low-fiber foods (light diet)

  • Vegetables with a high water content, e.g. zucchinis, tomatoes, leaf lettuce, cucumbers (peeled, without seeds)
  • Potatoes (cooked, peeled)
  • White rice
  • apple sauce (without skin)16

Low-fiber diet: not recommended in the long term

With the exceptions just mentioned, a low-fiber diet is not recommended for healthy people in the long term. 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 fiber. However, if we do not consume enough fiber, 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 fiber is associated with an increased risk of Cancer of the digestive tract is associated with an increased risk of digestive tract cancer.

In addition, a low-fiber diet is associated with constipation, digestive problems and a weakened immune system associated with this. A large number of diseases of civilization (e.g. obesity, heart attacks, strokes, type 2 diabetes) are also caused by a lack of dietary fiber.17

Low-fiber diet: Be careful with the following low-fiber foods

Dietary fiber is naturally found mainly in plant-based foods. Therefore animal productsespecially fish, meat and eggs, are not sources of health-promoting dietary fiber. Dairy products contain minimal amounts of fiber, but are still classified as low in fiber. These products should therefore in smaller quantities and in combination with wholesome, plant-based foods. be consumed.

Also strong industrially processed products (junk food, sweets, etc.) and processed flour (= white flour; consists only of the inner part of the grain - the fiber-rich outer layers are removed before grinding) are low in fiber and provide hardly any other valuable nutrients. You should therefore avoid these products as much as possible and only in exceptional cases enjoy18

List of low-fiber foods (not suitable as a light diet)

  • Meat
  • Fish
  • Eggs
  • Dairy products
  • sweets
  • Desserts made from white flour
  • Soft drinks
  • Junk food

Conclusion: Dietary fiber promotes digestion and prevents diseases

A balanced diet is characterized by an optimal ratio of proteins, fats and carbohydrates and a high density of micronutrients: at least 30 g of fiber daily.

Foods rich in fiber should make up the majority of your diet. As dietary fiber is a component of plant cells, it is also known as fiber and is found in almost exclusively in plant-based foods found almost exclusively in plant foods. We have summarized the most important sources of fibre for you here:

List of high-fiber foods

  • Fruit
  • Vegetables
  • Whole grain cereals
  • "Pseudocereals" (such as millet, quinoa and buckwheat)
  • Pulses
  • nuts
  • seeds

A large number of bodily processes are improved by a high-fiber diet: bowel movements, digestion, the development of positive intestinal flora and the elimination of toxins are the most important of these. Fiber is also said to have health-promoting and preventive effects.

Health-promoting and disease-preventing effects of dietary fiber

  • Dietary fiber prevents colon cancer
  • Dietary fiber reduces the risk of breast cancer
  • Dietary fiber strengthens the immune system
  • Dietary fiber prevents lifestyle diseases such as type 2 diabetes, heart disease, strokes and obesity
  • Dietary fiber increases life expectancy

A high-fiber diet therefore pays off. It is important that you gradually increase the amount of fiber in your diet, chew well and drink enough fluids.

FAQs: A summary of the most important facts about dietary fiber

What is dietary fiber?

Dietary fibers are indigestible, complex carbohydrates. 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 fiber?

Soluble fiberare 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 fiberon the other hand arecompletely indigestible. They serve as a filler in the intestine, provide a lasting feeling of satiety and stimulate digestion.

Why do we need dietary fiber?

Dietary fiber provides a good digestionpromote intestinal activity and elimination and have the following effects prevent the following diseases:

  • breast cancer
  • colon cancer
  • Heart disease
  • Stroke
  • Diabetes
  • Obesity

How much fiber should you eat per day?

To benefit from the health-promoting effects of fiber, you should consume at least 30 g of fiber per day. This is how you can cover your daily fiber 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 tablespoons)19

Is it possible to eat too much fiber?

Not in a natural way. However, caution is advised with high-fiber food supplements. If you have been on a low-fiber diet for a long time, a sudden, extreme increase can initially lead to digestive problems. To avoid this, you shouldfiber contentin your dietincrease gradually. This will allow your digestive system to slowly get used to the change. As fiber binds water, you should also avoidsufficient fluid intakemake sure you drink enough.

What are high-fiber foods?

Dietary fibers are in all plant-based foods. Particularly rich in fiber are:

  • Fruit
  • vegetables
  • Whole grain cereals
  • "Pseudocereals" (such as millet, quinoa or buckwheat)
  • Pulses
  • nuts
  • seeds

Are high-fiber foods healthy?

Yes.Dietary fiber is naturally found inwholesome, plant-based foodsfound in whole plant foods. These also contain a variety of other health-promoting substances such asvitamins, minerals and secondary plant substances. These foods therefore form the basis of a balanced diet.

What are low-fiber foods?

Animal products, highly processed foods and junk food contain little or no fiber. Low-fiber foods include:

  • Meat
  • fish
  • Eggs
  • Dairy products
  • sweets
  • Flour-based desserts
  • Soft drinks
  • Junk food

Sbalitelný obsah

Sources

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  3. Reischl, A. & Weidlinger, A. (2018). Ernährung: bewusst, aktuell, lebensnah (2nd edition). Linz: TRAUNER Verlag.
  4. Kaczmarczyk, M. M., Miller, M. J., & Freund, G. G. (2012). The health benefits of dietary fiber: beyond the usual suspects of type 2 diabetes mellitus, cardiovascular disease and colon cancer. Metabolism, 61(8), 1058-1066.
  5. Greger, M., & Stone, G. (2016). How not to die: discover the foods scientifically proven to prevent and reverse disease. Pan Macmillan.
  6. Broderick, N. A. (2015). A common origin for immunity and digestion. Frontiers in immunology, 6, 72.
  7. Korver, D. R. (2006). Overview of the immune dynamics of the digestive system. Journal of Applied poultry research, 15(1), 123-135.
  8. Korver, D. R. (2006). Overview of the immune dynamics of the digestive system. Journal of Applied poultry research, 15(1), 123-135.
  9. Brestoff, J. R., & Artis, D. (2013). Commensal bacteria at the interface of host metabolism and the immune system. Nature immunology, 14(7), 676-684.
  10. Slavin, J. (2013). Fiber and prebiotics: mechanisms and health benefits. Nutrients, 5(4), 1417-1435.
  11. A. Parnell, J., & A. Reimer, R. (2012). Prebiotic fiber modulation of the gut microbiota improves risk factors for obesity and the metabolic syndrome. Gut microbes, 3(1), 29-34.
  12. Greger, M., & Stone, G. (2016). How not to die: discover the foods scientifically proven to prevent and reverse disease. Pan Macmillan.
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  15. Liedenbaum, M. H., Denters, M. J., de Vries, A. H., van Ravesteijn, V. F., Bipat, S., Vos, F. M., ... & Stoker, J. (2010). Low-fiber diet in limited bowel preparation for CT colonography: Influence on image quality and patient acceptance. American Journal of Roentgenology, 195(1), W31-W37.
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