Dietary fiber is non-digestible food components of the carbohydrate group, found in products such as cereals, fruits, and vegetables. A distinction is made between soluble and insoluble fiber. They are absolutely necessary for the human organism because among other things they support digestion.
What is fiber?
Dietary fiber is part of the food that the human body cannot digest. In fact, the body cannot use these non-digestible food components, so it excretes them. However, these plant substances are extremely important.
A distinction is made between soluble and insoluble fiber.
Most fruits, but also oats, barley, or legumes, contain water-soluble fiber. They swell in relation to the fluid and also increase bowel movements.
They also serve as food for certain intestinal bacteria. These process what cannot be digested in short-chain fatty acids, which in turn have a very beneficial effect on people’s health.
It also regulates blood sugar levels, reduces inflammation and the risk of a heart attack or diabetes.
These fibers are found in the bran of various types of cereals such as wheat, oats, barley, but also soybeans. In addition, they are contained in the outer layers of fruits, vegetables, and seeds, or nuts.
For example, it is cellulose, the main component of plant cells, and lignin, which serves as a support material in plants.
Water-insoluble fiber contributes mainly to increasing stool volume and stimulating intestinal peristalsis (bowel movement).
These substances also benefit the intestinal microbiome, which is the totality of all microorganisms in the digestive tract. They lower the pH of the intestinal environment and are particularly beneficial in the treatment of constipation in relation to irritable bowel syndrome (IBS).
Even the so-called resistant starch of rice, legumes, and potatoes cannot be broken down by human digestive enzymes, that is, they cannot be digested. Its function is similar to that of water-soluble fiber.
Oligosaccharides are carbohydrates that consist of several individual compound sugar molecules. Bifido and lactic-acid bacteria from the intestinal flora are promoted by them and, therefore, by all intestinal health.
As prebiotics , these fibers have a positive influence on the bacterial composition of our digestive tract.
They are found particularly in plants such as turnip, chicory, garlic, asparagus, onions, or soy. Pure oligosaccharide inulin is available in pharmacies and health food stores.
What does fiber do?
Fiber “dilutes” the energy content of food and, therefore, promotes the feeling of satiety. They also cause food to be chewed for longer and better and make blood sugar rise more slowly.
These are all good prerequisites for losing weight or staying slim.
While insoluble fiber can stimulate intestinal activity and relieve common problems such as constipation, soluble fiber plays an important role, especially for metabolism.
Because the fiber binds to bile acids so that they are excreted more and more, which in turn increases the production of new bile acids in the blood, so cholesterol is consumed.
In addition, fiber is said to help prevent type 2 diabetes, colon and prostate cancer.
In general, a diet high in fiber may include gastrointestinal disorders (for example, constipation, diverticulosis, colon cancer, hemorrhoids), metabolic disorders (for example, obesity, diabetes) and cardiovascular diseases (for example, hardening of the arteries, attack heart, high blood pressure).
A minimum daily intake of 30 grams of fiber for adults is recommended. For example, this corresponds to approximately 200 grams of cabbage, 200 grams of carrots, 100 grams of beets, 100 grams of legumes, or three slices of whole wheat bread.
The easiest way to achieve the need for fiber is to eat many fruits and vegetables, as well as integral variants of popular products such as pasta, bread, and rice.
However, as the quantity increases, one must proceed with caution. Those who eat too much fiber and are not used to it often suffer from flatulence. At the same time, it is important to drink enough water so that the fiber swells enough.
Dietary fiber ensures a healthy intestine
Part of the fiber is broken down into short chain fatty acids by bacteria located in the large intestine (fermentation).
The gases and fatty acids generated during fermentation make the stool softer and bulky. Among other things, this can help reduce hemorrhoid formation.
Accelerated emptying of the intestine after a diet rich in fiber prevents these bumps. Most of it is not digested to the colon.
Due to its water retention properties, the fiber in the food swells in the large intestine. The amount of stool becomes larger and softer.
Dietary fiber strengthens the intestinal flora
These carbohydrates strengthen the intestinal microbiome. They are the complete microorganisms of our digestive tract. These are mainly bacteria that are involved in digestion and do not harm us in any way.
Therefore, it is a great advantage to keep the intestinal flora balanced:
- Water-insoluble fiber guarantees a regulated pH in the intestine.
- Water-soluble fiber serves as food for these intestinal bacteria and becomes healthy fatty acids.
- Oligosaccharides as prebiotics promote healthy bifido and lactic acid bacteria in our intestines.
Dietary fiber prevents colon cancer
In 2005, a European-level study led by the international agency for cancer research showed that dietary fiber even supports cancer prevention.
The eating behavior of more than 500,000 Europeans was examined. An average of 30 to 35 g of fiber reduced the risk of developing colorectal cancer by 25% compared to those who only consumed 15 g.
The reason for these surprising numbers is that fiber accelerates stool excretion. This causes the substances that cause cancer to come into contact with the intestinal mucosa for a shorter time.
In this way, the triggers of diseases such as heavy metals or pesticide residues pass through the intestine without causing problems.
Dietary fiber keeps us healthy
Dietary fiber lowers cholesterol
The fiber, particularly soluble in water, fruit, grains, and legumes are attached to the bile acid in the intestine which thus is excreted.
Short-chain fatty acids, which are produced when the water-soluble fiber is processed, also prevent the production of LDL cholesterol in the liver. As a result, blood vessels remain free of deposits, do not contract, and the risk of having a heart attack is reduced.
This was also confirmed by a study conducted by the University of Marseille in France. Researchers analyzed the nutritional behavior of more than 12,000 subjects over several years.
The result: the consumption of at least 30 g of fiber per day reduced the risk of coronary heart disease by 34%. The risk of heart attack also decreased by 27%.
Dietary fiber reduces the risk of diabetes
The absorption of sugar (glucose) in the small intestine is slowed down by water-soluble fibers. This has a positive effect on the regulation of blood sugar levels since it keeps it constant for longer and does not rise or fall from one moment to another.
A low blood sugar level causes tiredness and weakness, so we must eat sugary foods or drinks quickly again.
If the sugar level remains at an optimal level for a longer period of time, we feel full for longer. Diabetics also benefit since inflammation agents cause the insulin level to increase more slowly.
Dietary fiber helps you lose weight
Due to its high fiber content, foods rich in it should be chewed longer. This allows us to perceive when the feeling of satiety arises and hunger disappears.
Because water-soluble fibers swell in the gastrointestinal tract, the portion feels larger and we feel satiated for longer. The fat and calorie content is also relatively low with a high fiber diet.
Dietary fiber lowers blood pressure
Several studies have confirmed that a diet high in fiber can have a positive effect on blood pressure. Study participants who consumed enough fiber developed less high blood pressure than those with lower consumption during the study period.
A team of researchers from the Max Delbrück Center for Molecular Medicine and the Charité Universitätsmedizin in Berlin discovered that propionic acid is formed during the digestive process of the fiber.
Among other things, this can relieve inflammation. It also inhibits auxiliary T cells of the immune system, which causes inflammation to raise blood pressure to unhealthy levels.
Dietary fiber protects teeth
The teeth also benefit from high fiber content. Foods rich in it should be chewed well since they can only be swallowed with enough saliva.
The chewing activity stimulates the gums and cleans the surfaces of the teeth.
Saliva rinses teeth and helps cushion harmful acids, which would otherwise attack tooth enamel and promote tooth decay.
As described above, plant foods provide large amounts of fiber. With a content of approximately 5 g, there is talk of food rich in it.
- Fruits, such as apples or pears.
- Vegetables, especially carrots, potatoes, and cabbage
- Integral products such as bread and pasta.
- Legumes (beans, lentils, etc.)
What fruits and vegetables contain a high fiber content?
- Pineapple can complement gastric juice and increase protein digestion.
- Chicory stimulates the metabolism due to the bitter substances it contains: store it in a cool, dark place, wash quickly and process it raw.
- Figs help with constipation. Soak the fruit in water or milk for a few hours before eating it.
- Cucumber stimulates bowel activity. Daily consumption helps with chronic constipation.
- Due to its good swelling capacity, oatmeal (as whole grains) is excellent for stomach and intestinal diseases. It tastes great in muesli or pancakes.
- Legumes (for example, peas, lentils, or soybeans) have an extremely high fiber content: cook gently, puree, and add “deflating spices,” such as caraway, ginger, or coriander.
- Carrots can almost completely replace laxatives: they are eaten raw or chopped.
- Flax seeds act as a mild digestive aid: before breakfast, sweeten a cup of warm milk with honey and add a tablespoon of freshly crushed flax seeds.
- Plums are a wonderful weapon in terms of digestion: always eat raw and supplement with fat (for example, with nuts).
- Rhubarb has a mild laxative effect due to the classic anthraquinone laxative active ingredients.
- Rye (as whole grain) stimulates digestive juices, promotes intestinal peristalsis, and is mainly a grain for baking.
- Sauerkraut is ideal for constipation: do not wash, just cook gently. It is also edible as a salad.
- Wheat (as whole grain): Your bran is an excellent source of fiber. Wholemeal flour can be processed in bread and pasta.
- Onions stimulate the digestive glands and improve intestinal flora; It is better to eat them raw.