Fiber in food – how much to consume and what benefits it offers?

If you want to improve your performance and health, you should consume enough fiber. Unfortunately, we live in a world that processes food and therefore it often deprives them not only of fiber but also of valuable nutrients such as vitamins and minerals. Therefore it is not easy to get enough fiber from diet and take all the benefits it offers.

In this article we will share what fiber is, what benefits it offers and we will have closer look at the signals of its lack. In addition we will find out how much fiber we should consume every day and we will give you tips how to increase its intake.

Fiber in food - how much to consume and what benefits it offers?

Fiber – what is really is?

Fiber is the term for the part of a food that in unchanged form passes through the digestive tract and is not subject to enzymatic cleavage or absorption. Our body can not digest it because we do not produce the necessary enzymes for it. In literature, the terms crude fiber or unusable carbohydrates are used. If we add hemicelluloses and pectin (both are polysaccharides) to this group, we call this extensive group of substances „dietary fiber“. Other, more or less known food ingredients, such as vegetable gums and mucilage are also called dietary fiber. They are all compound sugars.

There are two types of fiber: soluble and insoluble

Soluble fiber partially dissolves in water and turns into gel by cooling. It can also be digested and metabolized by bacteria in the colon. The result of this process is gas and short-chain fatty acids that can be absorbed by the body in small amounts. This kind of fiber is found in nuts, vegetables, legumes, cereals, fruits, oat flakes and seeds. According to researches, this soluble dietary fiber lowers the level of cholesterol and slows absorption of glucose which reduces sugar fluctuations in the blood.

dijetalna topljiva i netopljiva prehrambena vlakna

insoluble fiber does not dissolve in water and unchanged passes through the digestive tract. This increases the body’s ability to form the excrement and move it through the digestive system. If can be found in vegetables, grains, whole grain products, whey bran and seeds.

According to the researches, it speeds up the passage of food through the stomach and intestines and likely it reduces the risk of colon cancer and rectal cancer.


Vegetables, fruits and any vegetable product contain both soluble and insoluble fiber, but this ratio varies depending on the type and degree of ripeness of vegetables and fruits.

Since we do not produce the enzymes required for its break, tie fiber can enter the intestines unbroken. Once it reaches the colon, it acts as a food for beneficial bacteria. An increased amount of good intestinal bacteria improves functions of immune system and suppresses irritation and inflammation. And you want to feed these good bacteria so they can develop and prevent the bad ones from taking over your intestinal micro flora.

It is extremely important to have healthy bacterial balance in intestines. Many studies have shown the numerous benefits of maintaining healthy intestinal bacteria. In addition, disrupted bacterial balance (disbiosis) may change gene expression in the brain.

Gene expression is a complex process of expressing genetic information stored in DNA. The process of gene expression is not static but some dynamic changes may happen in it as a response to changes in the cellular environment.

Your intestinal bacteria also help to synthesize vitamins (B2, B5, B6, biotin and vitamin K). Vitamins B2 and B5 play a vital role in the production of ATP (adenosine triphosphate) which releases energy. Without these vitamins you can not perform well in the gym or on the playground.

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Fiber and its effects

Fiber has a positive effect on the time at which the intestinal wall is exposed to possible harmful substances in the diet because it accelerates the passage of digested food through the intestines. It also lowers the level of cholesterol, helps to fight obesity, prolongs satiety and helps diabetics to maintain more stable sugar levels. In addition, it affects the speed of nutrient absorption, increases the capacity of digested food, removes constipation and is an effective means for people suffering from hemorrhoids and gall bladder problems. It also positively affects the condition of the gums and the occurrence of dental caries.

Fiber in food - how much to consume and what benefits it offers?

Its most important abilities can be derived from English language:

• F – fullness

• I – Insulin control

• B – Beneficial bacteria

• E – Expectancy

• R – Regulation

Fiber and satiety

Fiber supports gastric saturation in two ways – it materializes food into a larger mass and slows digestion. Since the stomach is not interested in the number of calories taken but in the amount of food taken, the dietary fiber causes a feeling of fullness. In addition, dietary fiber belongs to carbohydrates and depending on the structure, it provides a small amount of energy (about 2 calories per gram, i.e. 8 kJ / g).

Fiber and insulin control

The benefits of slow digestion are increased insulin sensitivity and glucose control in blood. Eating high-fiber foods slows the entry of nutrients into the blood. For example, slower release of glucose into the blood allows insulin to be more efficiently distributed. Whatever your goals are, increased insulin sensitivity creates the right conditions for a good body composition.

Fiber and insulin control

Consume fiber, get rid of harmful substances

Fiber helps normal excrement so you need to consume enough fiber. Your intestines push undigested foods along muscle contractions, and if your excrement are okay, it moves more easily in your intestines.

The reason why you go to the toilet is because your body gets rid of harmful substances. If you allow the waste to rest in your digestive system for too long, you will begin to reabsorb these pollutants. A body that is burdened with re-absorption of pollutants does not have the capacity to get rid of new pollutants entering the system. This means that pollutants continue to accumulate in your body, which can lead to numerous health problems.

Pollutants in excrement are reflected by some of the following problems:

• fatigue

• nervousness

• stomach and intestinal problems

• poor nutrient absorption

• skin issues • endocrine disorders

• headache

• arthritis

• lower back pain

• sciatica (inflammation of the sciatic muscle)

• allergies

• asthma

• cardiac arrhythmia

• pathological changes in the breasts

Fiber in food - how much to consume and what benefits it offers?

How much fiber to consume?

Eating fiber is important not only for health, good excrement and regular toilet visits, but also for your performance. Women are recommended to consume about 25 grams of fiber a day, men to eat 38 grams. The recommended ratio of soluble and insoluble fiber is 3: 1.

However, the recommended daily fiber intake is different in some countries (for example, in Denmark 20-30 grams per day or in Greece 15-20 grams per day), depending on the analytical method used to determine it. 

For example, Hadza – an indigenous tribe from Tanzania, consumes 100 – 300 grams of fiber per day. In Slovak Republic the average intake is about 12 grams of fiber per day, while less than 25 grams of fiber is taken up by about 98% of the population. We should not exceed the recommended daily dose, more than 60 grams per day is considered as a risky intake. This could lead to nutrient absorption disorders.

The best sources of fiber

Eat fiber-rich foods. In general, you should consume raw fruits, vegetables and legumes. They keep the fiber unbroken while cooking degrades its content. Many experts recommend consuming fiber in the form of raw fruits and vegetables in every meal.

The best sources of fiber
The best sources of fiber

The main source of insoluble fiber are mainly cereals, whole grain bakery products – such as bread, pastries, pasta and oat flakes. It is also present in the skin of apples, pears, grapes and potatoes.

Soluble fiber is likely to be found in fruits and vegetables. For example, in citrus fruits, bananas, apples, pears, currants, carrots or cabbage. In the form of edible gum it occurs in beans, oats and barley. In the form of slime it is found in flax seeds and seaweed.

Fiber in food - how much to consume and what benefits it offers?

Important source of dietary fiber in our diet are also other legumes – peas, soy, lentils and chickpeas. It is also found in nuts, poppy seeds and dried fruits.

With fiber-rich foods you should increase also fluid intake to avoid constipation. 

To ensure varied daily fiber intake, here are few tips how to quickly and easily supplement it:

  1. Try to eat more fruits instead of drinking fruit juices.
  2. Do not forget to consume vegetables – whether cooked or raw.
  3. Instead of white flour pastries, try 100% wholemeal bread.
  4. Change white rice to brown. You can also eat jasmine rice.
  5. If possible, add legumes to your meal – for example to salad, soup, or main course.
  6. If you have trouble receiving fiber from foods, use available dietary supplements.
Fiber in food - how much to consume and what benefits it offers?

If you are not able to consume enough fiber from food, try dietary supplements such as psyllium to supplement your intake. Freshly ground flax is also great, especially for people with more sensitive intestines. Pectin is more expensive fiber supplement solution, but is an excellent alternative for smokers or former smokers as it helps bind and pull heavy metals such as mercury from the body.

Fiber and its benefits

If you will take enough fiber from your diet every day, it will help your health. Fiber supports good bacterial balance in the digestive tract and helps to eliminate toxins from the intestines regularly. If you do not have a regular excrement, then you certainly need more fiber and probably also water. In addition, sufficient fiber intake will also help to get more energy, your performance and your health.


[1] Hill, M J, Intestinal flora and endogenous vitamin synthesis, European Journal of Cancer Prevention – https://pubmed.ncbi.nlm.nih.gov/9167138/

[2] Hoban, A. E., et al., Regulation of prefrontal cortex myelination by the microbiota – https://www.nature.com/articles/tp201642

[3] Jensen, B. Dr. Jensen’s Guide to Better Bowel Care – https://www.amazon.com/Jensens-Guide-Better-Bowel-Care/dp/0895295849?ie=UTF8&*Version*=1&*entries*=0

[4] Anderson JW, Baird P, Davis RH Jr, Ferreri S, Knudtson M, Koraym A, Waters V, Williams CL., Health Benefits of dietary fiber – https://pubmed.ncbi.nlm.nih.gov/19335713/

[5] KOHOUT, P., CHOCENSKÁ, E. Průzkum příjmu vlákniny v České republice. Výživa a potraviny, 62, 2007, č.5, s.129.

[6] SLUKOVÁ, M., RAKOVÁ, L. Vláknina potravy a cereální výrobky. Výživa a potraviny, 2010, č.5, s.131-133.

[7] AACC Report „Report of the Dietary Fiber Definition Committee to the Board of Directors of the American Assotiation of Cereal Chemists, Submitted January 10, 2001“: Cereal Foods World 46, 2001, p. 112 – 126.

[8] Hejda, J.: Vláknina pro zdravé a nemocné. Praha, SPV, 1994, 36 s.

[9] Kajaba, I. a kol.: Odporúčané výživové dávky pre obyvateľstvo SR. Vestník MZ SR, 45, čiastka 7 – 8, zo dňa 28.04.1997.

[10] Krkošková, B. – Kováč, M.: Metódy analýzy vlákniny v potravinách a overenie vybranej metódy v laboratórnych podmienkach. Štúdia. VÚP, Bratislava, 2001, 14 s.

[11] Miko, M. – Janíček, I. – Kajaba, I.: Základy výživy. STU Bratislava, 1996, 132 s.

[12] Petríková, D.: Fibertec Systém E – stanovenie potravinovej vlákniny. Bulletin, roč. IV, č. 2, Bratislava, 2000, 4 s.

[13] Salvini, S. – Parpinel, M. et al.: Banca Dati di Composizione Degli Alimenti per Studi Epidemiologici in Italia. Milano, 1998, 958 p.

[14] Smrčinová, H. – Ouhrabková, J.: Závěrečná zpráva projektu EP9025 „Vláknina potravy a potravinářských produktů“, VÚP Praha, 2001, 23 s.

[15] STN 56 0031 Poľnohospodárske a potravinárske výrobky. Stanovenie potravinovej vlákniny. Bratislava, SÚTN, 1999.

[16] Štatistický úrad SR: Spotreba potravín v SR (definitívne údaje) Bratislava, 2002, 20s.

[17] Štiková, O. a kol.: Stanovení výživových doporučených dávek pro průmerného obyvatele SR a optimalizační výpočty doporučených dávek potravin. Praha, VÚZE/ Bratislava, VÚP, 1998, 13 s.

[18] Trichopoulou, A.: European Journal of Clinical Nutrition, Vol. 44, No. 2, 1990, p. 3 –125.

[19] Vestník MPSR, ročník XXXIV, 15. júl 2002. Čiastka 14, 74.: Výnos MPSR z 24. júna 2002 č. 1519/2002-100. Príloha č. 2: Stanovenie množstva vlákniny v potravinách enzymaticko-gravimetrickou metódou.