What are fibers and what role do they play in nutrition?
Fibers have long been considered unimportant for the body.
That this is not true, has only become clear later. For fibers are an indispensable element for a balanced and healthy nutrition.
What types of fibers are there?
Fibers are among the carbohydrates and can be divided into insoluble and soluble fibers due to their different properties.
Insoluble fibers (the majority of fibers)
- Cellulose: Wheat bran, whole grain products, vegetables
- Hemicellulose: Cereal grains, oats, rye, barley, legumes, fruits, vegetables
- Lignin: Corn, lignified vegetables
- Chitin: Mushrooms, articulate animals
Soluble fibers (types of sugar, starch – can be digested by enzymes in the large intestine)
- Pectin: Apples, quinces, pears, fruit, vegetables, legumes
- Marine-algae extracts – agar agar, carrageen: algae
- Seed mucilage: Locust bean gum, guar gum, linseeds, psyllium, chia seeds
- Natural gum, acacia gum: Vegetables, bark from different acacia
- Fructosans: Onions, leek, asparagus
- B-glucans: Oats, rye, barley, mushrooms
- Resistant starch: Glucose; starch granules difficult to attack
How do fibers work?
Fibers have a variety of different properties depending on the category.
They stimulate chewing
Due to fiber structure, especially of cellulose and lignin, the food has to be chewed more intensively, which also stimulates the saliva flow. This supports tooth cleaning and neutralizes microbially formed acids, which has positive effects on dental health. The increased chewing effort also slows down food intake and triggers satiety stimuli, which usually means that less food is eaten overall.
Water binding, swelling properties, long-lasting saturation:
The water-binding and swelling properties increase the viscosity, i. e. the fluidity and volume of the stomach content. This delays the emptying of the stomach, which leads to longer satiety.
Swelling types of fiber delay the passage time of chyme through the small intestine, while fiber-like and water-insoluble fibers as well as the mucous substances speed up the passage time. This is why fibers are so appropriate to regulate intestinal disorders, such as constipation, and to improve bowel movements overall.
Positive effect on blood sugar and insulin levels:
Some gel-forming dietary fibers hinder enzymes during digestion, so that glucose can be absorbed more poorly, flows more slowly into the blood and thus blood sugar and insulin levels rise less.
Binding cholesterol and environmental toxins
Some dietary fibers, such as pectin, have the ability to bind to environmental toxins or even excess cholesterol and eliminate them from the body. This can reduce fat absorption, lower blood cholesterol, and decrease the deposit of toxic heavy metals and other pollutants.
Promote microflora and lower pH value
Due to the structural properties of dietary fiber, the multiplication of preferable colon bacteria is promoted and undesirable germs are lowered, among other things, by lowering the pH value. Thus, the microflora of the intestine is strengthened and can better protect against nutrition-related diseases.
Use in the food industry
Some of the listed dietary fibers look familiar to us from convenience foods and various processed foods, as their use is widespread in the food industry.
The food industry particularly appreciates the water-binding and gel-forming properties of a wide variety of dietary fibers (locust bean gum, guar gum or carrageen, xanthan and alginates) and likes to use them as stabilizers and thickeners.
Just as popular, however, are the water-soluble dietary fibers oligofructose and inulin, which have a slight sweetness and give some low-fat products a creamy consistency. However, some of these dietary fibers, which are extracted or produced by chemical processes, are suspected of promoting diseases. Such as carrageen, which is suspected of being carcinogenic and therefore banned in infant food.
How much fiber should be eaten daily?
The German Society for Nutrition (DGE) recommends an amount of 30g of dietary fiber per day. Metabolic Balance also recommends this amount and takes it into account when creating personalized nutrition plans.
To meet one’s daily requirement of 30g of fiber, nutrition must include plenty of fruits and vegetables, as well as whole grains and legumes. For example, 3 slices of whole meal bread, 250g of vegetables, 300g of fruit and 200g of potatoes can cover the daily requirement.
Exclusively isolated fiber in the form of psyllium, chia seeds or wheat bran cannot replace fiber-rich foods. However, these can be added as a useful supplement to nutrition, e.g. in cereals (psyllium husks). Be aware: After ingesting isolated fiber such as psyllium husks, chia seeds or wheat bran, in any case drink 1-2 large glasses of water. Only then the dietary fiber can swell properly and develop its positive effect. If this is not taken into account, among other things, constipation can occur, as the dietary fiber pulls the required water from the intestinal content.
What happens if too little fiber is eaten?
If too little dietary fiber is ingested, this can lead to various negative effects:
- Changes in the intestinal wall and intestinal mucosa
- Obesity, cardiovascular diseases, diabetes type 2
- Tumors in the colon and rectum
As mentioned at the beginning, the assumption that fiber is unimportant and does not benefit our health can be clearly refuted. A sufficient daily intake of fiber is essential for a balanced and healthy nutrition. This cannot only treat nutrition-related diseases, such as constipation, but also, above all, do something for your health in a preventive way.
Those who eat according to their individual Metabolic Balance nutrition plan can be sure that they consume the recommended amount of 30g of dietary fiber per day. With the balanced ratio of proteins to carbohydrates in the form of fruit and vegetables, as well as the many starchy foods such as whole meal rye bread, oatmeal, potatoes or wild rice, as they prevail in the personalized Metabolic Balance nutrition plans, nothing stands in the way of a fiber-rich, balanced, healthy and preventive nutrition.