Effects of fiber on the body

In the mouth the high fiber food that we have ingested has two actions: on the one hand stimulates saliva production, which already begins the degradation of the food through the enzymes it contains; secondly, it stimulates the production of juice by the stomach (gastric juice).

In his step through the esophagus no major changes occur:. This digestion will be enhanced later by the action of new enzymes manufactured by the pancreas and released into the intestine.

The stomach It has a function on the food as if it were a mixer, so that later the enzymes of the pancreas contact the maximum amount of food and it is easily absorbed through the wall of the intestine.

All the way from the mouth, fiber (insoluble) absorbs water. Since fiber is not degraded by enzymes in saliva or by enzymes in the pancreas and, in addition, it captures water, a structure is formed that fills the stomach, producing Feeling full, and that slows down (due to the effect of soluble fiber but not insoluble fiber) the gastric emptying of the food, with which the feeling of satiety is maintained for a longer time.

In the first sections of the small intestine, although they are not the only ones, food is absorbed. The fiber that accompanies these digested ("shredded") foods slows its absorption somewhat, which is important in the case of the sugar to be absorbed, as it prevents everything from being absorbed at once. This reduces the sugar spike that reaches the blood when we eat, very harmful both in healthy individuals and in diabetics.

Fiber types

The insoluble fibers they are little or not fermented by the action of the bacteria in the colon, they are not viscous (they have little capacity to form gels) and they are excreted practically whole in the feces.

The soluble fibers they ferment rapidly due to the action of colonic bacteria and are viscous. These physical characteristics, together with the ability or inability to retain water, are closely related to its physiological effects, but ... do we know what the effects of fiber are in the body?

Effects of fiber in the body: Decrease in cholesterol

On the other hand, fiber would be able to sequester bile acids (at least in part), limit the y of fatty acids in the intestine, and all this would lower blood cholesterol levels.

Fiber also modulates the rate at which food travels through the intestine as it is absorbed. Depending on the type of fiber ingested this would achieve an effect of more "movement" of the intestine (insoluble fiber) or less "movement" (soluble fiber).

In addition, the major or minor velocity of food through the digestive tract it would facilitate or hinder the contact of toxic substances on the wall of the intestine and colon, which in some cases would be the origin of tumors.

Fiber and its effects on the body: hemorrhoids, fissures and bleeding

We reach the colon, where the bacteria act on that fiber that our enzymes have not managed to break down. Fiber is attacked by bacteria in the colon, producing mainly short-chain fatty acids (acetic, propionic and butyric) and other substances such as carbon dioxide, hydrogen and methane (which are gases).

The acetic acid It is the only one of these acids that reaches the systemic circulation and can be used as a source of energy and in the formation of fat; propionic acid reaches the liver, where it could decrease cholesterol synthesis and thereby lower blood cholesterol levels. The butyric acid it is a good source of energy for the cells of the colon wall. Stool is made up of fiber and other undigested substances, cells in the intestinal wall that are lost, water, and bacteria from the colon. That of the stool is inversely related to the fermentation of fibers in the colon. The less fermentation ("destruction") of the fibers by colon bacteria, as with insoluble fibers, there is a increased water retention and a increased fecal volume. And vice versa.

Another aspect to take into account is that, the more mass "stored", that is, the more mass that reaches the colon, the more these stools stimulate the motility of the colon and, with this, the less constipation and less hard stools that pass through the anus (which improves hemorrhoids, fissures and bleeding from the anus).

But fiber can decrease the nutritional utilization of, particularly iron and calcium, due to an interaction in intestinal absorption. This is important in excessively high fiber diets but not in regular feedings.

The effects of fiber can negatively affect the body. To find out if you need a diet rich in fiber, consult your doctor, remember that MAPFRE has those with a wide medical staff of specialists in internal medicine and nutritionists.