The role of dietary fiber in the process of digestion
Last reviewed: 23.04.2024
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Rough "food" - this is just the vegetable dietary fiber. There are these fibers of both carbohydrate and non-carbohydrate nature. The first group includes cellulose (or fiber) and hemicellulose, and the second group includes pectin and lignin.
What are the food fibers built from?
All dietary fibers are natural polymers, that is, they consist of a chain of identical substances and compounds. So, for example, a link in the chain of cellulose is known to all glucose. In the chain of hemicellulose, the units are xylose and galactose, as well as sugars. Pectin, for example, is formed from galacturonic acid, and from phenylpropane (a natural polymer obtained from the bark of a tree) is a constituent of lignin.
A variety of dietary fiber can be contained in the biologically active substances of the body - vitamins, in mineral compounds and some other components of the body.
How does the dietary fiber affect the body?
When dietary fibers enter the body, they are slightly processed and slightly destroyed by the intestinal microflora. According to the results of the research, only 38% of cellulose, 35% of lignin and 56% of hemicellulose are digested and absorbed by the body. How well the product is digested depends not only on the chemical properties of the product, but also on the degree of its grinding. If you eat bran bran, then they are much worse than the bran of finer grinding. Even without grinding, food fibers can not bring too much energy into the body. So, from 100 g of such a product, the body can get no more than 400 calories.
If you regularly eat foods rich in dietary fiber, then due to this greatly increases the amount of feces and stimulates the work of the intestines. With a lack of the same dietary fiber in foods can lead to intestinal atony and constipation. The proof of this fact is that among rural residents and vegetarians who consume a lot of food of plant origin, feces are larger than urban residents and people who often consume meat.
Consumption of dietary fiber in the world
In the developed countries, consumption of plant foods has fallen by almost 90%. The development of the food industry and the introduction of technological innovations have done their job - now there is a huge amount of refined products. Thus, with the improvement of grinding technology, the amount of fiber in the flour has sharply decreased. Even in the last century, people consumed at least 15-20 grams of dietary fiber per day, but now this number has dropped significantly: in Germany, people consume no more than 5 grams, in the UK no more than 4-8 grams, with the United States about 8-11 grams, in Russia, 6-8 g of dietary fiber.
[What should you eat and what not?
Now it is believed that in order for the intestine to function properly, a person should consume at least 25 g of dietary fiber. But we naturally prefer to choose already refined, with a variety of flavor additives and seasonings, refined foods than useful natural products - vegetables, fruits, rye bread and coarse bread. This is the reason for such a common problem as constipation, because irrational nutrition is clearly not good.
Other properties of dietary fiber
In addition, that dietary fibers prevent the appearance of constipation and have a beneficial effect on the intestine, they have many more useful properties. Dietary fibers are able to improve the metabolism in the body, due to the effect on different systems of the body. They purify the intestines and remove toxins, as they possess sorption abilities. Dietary fiber can significantly reduce the likelihood of malignant tumors in the gastrointestinal tract.
If you regularly consume vegetable products of coarse grinding, you can reduce the concentration of glucose, cholesterol and triglycerides in the blood, and also reduce weight. It is for this reason that plant foods are indispensable in the diet of people suffering from diabetes, obesity, ischemic heart disease, atherosclerosis and a predisposition to these diseases.