By “fiber” we define all compounds of plant origin that are not digested. It is found only in vegetables, it is not present in foods of animal origin.
There are two types of fiber, soluble and insoluble fibers.
Soluble fibers
These are the gums, pectins, mucilages, algal polysaccharides and beta-glucans. They form a large-volume gel in the small intestine, which retains water, slows digestion, decreases postprandial glycemia and reduces insulin production. They perform a probiotic action on the bacterial flora. They are found in legumes, fresh fruits (especially plums and berries), oats and oat bran, vegetables such as carrots, potatoes, onions, sweet potatoes.
Insoluble fibers
These are the long fibers, such as cellulose and lignin. They hold more water than soluble fibers, especially in the large intestine. They cause an increase in fecal weight, in the speed of transit and intestinal emptying, thus regularizing the intestine. They are found in all whole grains, green leafy vegetables, dried fruits, bran and seeds, especially flax seeds.
We sometimes hear fiber referred to as an “anti-nutrient” because fiber intake can lead to a decrease in mineral assimilation; foods that are higher in fiber are also very high in minerals. It has been verified that problems in assimilation occur only if fiber is taken not from food, but artificially, in the form of bran powder or tablets, methods used by those who do not consume enough plant foods.
Fiber is an essential component of the daily diet and its limited intake can have negative health consequences.
Regular fiber intake, on the other hand, produces positive short-term and long-term effects:
increased sense of satiety, which allows you to take less food and not exceed calories;
intestinal regulation;
decrease in the exposure time of the cells of the intestinal mucosa to harmful substances contained in food;
in the case of soluble fibers, creation of a protective film on the inner surface of the mucosa of the digestive tract;
stabilization of postprandial glycemia;
reduction of the risk of formation of diverticula and hemorrhoids;
improvement of the composition of the intestinal bacterial flora (with a greater presence of “good” bacteria);
reduction of cholesterol levels in the blood;
decrease in the risk of vascular diseases;
decrease in the risk of certain types of cancer (colon, breast, prostate).
A good fiber intake is, ultimately, fundamental to human health.
In young children (up to 2 years of age), fiber intake must be limited, especially because if children eat too much fiber, the sense of satiety comes too soon, with the risk that they do not eat enough, not taking in all the nutrients needed for their growth and development.
Another aspect is the “sponge effect”, due to insoluble fibres, which cause an increase in the volume of food: children’s intestines have a very small diameter and fibre slows down transit, instead of helping it as it does in adults. This gives rise to the so-called “paradoxical constipation”, with various associated symptoms: digestive disorders, gaseous colic, slow growth, lack of appetite.
For this reason it is necessary to apply the following measures during weaning:
Vegetables: initially use only broth, then pureed vegetables.
Cereals: if in flour, use those with a fiber content of less than 4 grams per 100 grams, or sift the whole grain flour, the grains should be cooked and then passed through a vegetable mill.
Legumes: use peeled ones, or whole ones mashed or peeled by hand once cooked.
In general, fruits and vegetables should be limited in order to favor the consumption of more caloric foods.
It is important, slowly over time, to increase the quantity of fibers: adding to vegetable broth a little bit of puree, to creams of cereals and defibrated legumes a little bit of the fibers that have been removed.
Graduality is essential and must be based on the individual response of the child: if you notice a decrease in the frequency of evacuation or even the appearance of constipation, it is necessary to stop.