classify
Dietary fiber is a kind of carbohydrate that human body can't digest. According to the solubility in water, it can be divided into two basic types: water-soluble fiber and water-insoluble fiber. Cellulose, hemicellulose and lignin are three common water-insoluble fibers, which exist in plant cell walls. Pectin and gum are both water-soluble fibers and exist in non-fibrous substances in nature. Common foods, such as barley, beans, carrots, oranges, flax, oats, oat bran, etc., are rich in water-soluble fiber, which can slow down digestion and expel cholesterol as quickly as possible, so that blood sugar and cholesterol in the blood can be controlled beyond the ideal level, and it can also help diabetic patients reduce insulin and triglycerides.
Water-insoluble fibers include cellulose, lignin and some semi-fibers, as well as wheat bran, corn husk, celery, peel and root vegetables from food. Insoluble fiber can reduce the risk of intestinal cancer, prevent constipation and diverticulitis by absorbing toxic substances in food, and reduce toxins discharged by digestive tract bacteria. Most plants contain water-soluble and water-insoluble fibers, so a balanced intake of water-soluble and water-insoluble fibers in the diet can obtain different benefits.
Daily intake standard
The daily intake of dietary fiber recommended by relevant international organizations is 30-40g per person per day recommended by American Cancer Society and 30g per person per day recommended by European Committee for Homogeneous Food Science.
What food contains the most dietary fiber?
Brown rice and embryo polished rice, as well as miscellaneous grains such as corn, millet, barley, wheat bran and wheat flour (the material of black bread); In addition, there are many dietary fibers in root vegetables and seaweed, such as burdock, carrot, mung bean, red bean, pea, potato and Undaria pinnatifida.
Dietary fiber is a plant component, and plant food is a natural food source of dietary fiber. Vegetables, fruits, coarse grains, beans and bacteria and algae are rich in dietary fiber. The content of dietary fiber in some common food raw materials is: Chinese cabbage 0 .7%, white radish 0 .8%, water spinach 1. Zizania latifolia 1. 1%, leek 1. 1%, garlic sprout 65438. 2. Soybean 1%, Bitter Melon 1. 1%, Ginger 1 .4%, 1. 4% of strawberry, 1. Apple 2 %, 65438+ fresh jujube and jujube 0 .6%.
6.7%, Chinese yam 0 .9%, millet 1. 6%, corn flour 1 .8%, mung bean 4 .2%, Tricholoma matsutake 6 .9%, tremella fuciformis 2 .6%, auricularia auricula 7 .0% and kelp 9 .8%. With the deepening of people's understanding of the relationship between dietary fiber and human health, some high-fiber foods are increasingly favored, and the proportion of bacteria, algae, fruits and vegetables in the dietary structure is gradually increasing. In modern food industry, rice bran, wheat bran, rye, oats, bean dregs and other raw materials rich in dietary fiber are processed through a series of processes to produce corresponding dietary fiber products, which can not only be developed into direct oral dietary fiber products, but also be used as food additives, such as adding to fermented foods such as yogurt, bread and other baked goods as quality improvers and dietary fiber enhancers.
Among many local dishes, some dishes are famous for their vegetarian dishes, rich in dietary fiber and local characteristics, and then become local famous dishes. Traditional famous dishes rich in dietary fiber include "Dictyophora edulis stuffed with snowflakes", "Jade Jade Jade Ring", "Colorful shredded chicken" and "Tri-colored turtle". Su cuisine includes steamed scallops with onion, fried chicken with taro, stewed tofu with mushrooms and bamboo shoots, and jade tendon. There are some famous dishes in hubei cuisine, such as "preserved pork and vegetable moss", "roasted bacon with wormwood", "stewed ribs with lotus root" and "steamed three times in Mianyang", as well as "stewed silver carp with moldy bean dregs" and "roasted pork belly with moldy bean dregs". Shandong cuisine includes "onion and sea cucumber", "shepherd's purse fish roll", "three-silk wrapped fish" and "fried leek". Sichuan cuisine includes fish-flavored shredded pork, boiled cabbage, boiled pork slices and cowpea powder.
profit
Keep the digestive system healthy
boost one's immune system
Lowering cholesterol and hypertension
Reduce insulin and triglycerides
◇ Relaxation, diuresis, clearing intestine and invigorating stomach
Prevent cardiovascular diseases, cancer, diabetes and other diseases.
Balance hormones in the body and reduce hormone-related cancers.
efficacy
First, prevention and treatment of constipation: a large amount of dietary fiber can promote intestinal peristalsis and reduce the residence time of food in the intestine, and the water in it is not easy to be absorbed. On the other hand, dietary fiber is fermented by bacteria in the large intestine, which directly absorbs the water in the fiber, softens the stool and has a laxative effect.
Second, it is beneficial to lose weight: most obese people are related to increased calorie intake or decreased physical activity in food. Increasing the dietary fiber content in the diet can reduce the intake of heat energy, reduce the digestion and absorption of nutrients in the intestine, and finally make the body fat consumption play a role in losing weight.
Third, prevention of colon cancer and rectal cancer: The occurrence of these two cancers is mainly related to the long stay time of carcinogens in the intestine and the long contact time with the intestinal wall. Increasing the content of dietary fiber can reduce the concentration of carcinogen, and dietary fiber can stimulate intestinal peristalsis, which greatly shortens the contact time between carcinogen and intestinal wall. Scholars agree that a long-term diet high in animal protein and insufficient fiber intake are the important causes of these two cancers.
Fourth, the prevention and treatment of hemorrhoids: the occurrence of hemorrhoids is caused by long-term blood stasis caused by constipation. Because of the laxative effect of dietary fiber, it can reduce the pressure around the anus and make the blood smooth, thus playing a role in preventing and treating hemorrhoids.
5. Reduce blood lipid and prevent coronary heart disease: Because some components in dietary fiber, such as gum, can be combined with cholesterol, lignin can be combined with cholic acid, so that it can be directly discharged from feces, thus consuming cholesterol in the body to supplement cholesterol consumed in bile, thus reducing cholesterol, thus having the effect of preventing coronary heart disease.
Sixth, improve the symptoms of diabetes: pectin in dietary fiber can prolong the residence time of food in the intestine, reduce the absorption rate of glucose, so that blood sugar will not rise sharply after meals, which is conducive to the improvement of diabetes. In recent years, some scholars have shown that dietary fiber has the function of lowering blood sugar. Experiments show that 26 grams of edible corn husk (containing 9 1.2% fiber) or soybean husk (containing 86.7% fiber) is added to the diet every day. Results After 28-30 days, the glucose tolerance was obviously improved. Therefore, increasing dietary fiber in diabetic diet for a long time can reduce insulin demand and control postprandial metabolism, which should be used as an auxiliary measure for diabetes treatment.
Seven, improve the function of the mouth and teeth: Modern people have fewer and fewer opportunities to use oral muscles and teeth because food is more delicate and softer. Therefore, tooth loss and dental caries are becoming more and more common. Increasing the cellulose in the diet will naturally increase the chances of chewing with oral muscles and teeth. In the long run, the oral cavity will be healthy and its function will be improved.
Eight, prevention and treatment of gallstones: the formation of gallstones is related to the high content of bile cholesterol, because dietary fiber can bind cholesterol and promote bile secretion and circulation. Therefore, the formation of gallstones can be prevented. Some people add 20-30 grams of bran fiber to patients every day, and after one month, gallstones can be found to shrink, which is related to smooth bile.
Prevention of female breast cancer: According to epidemiological investigation results, the occurrence of breast cancer is related to the intake of high fat, high sugar, high meat and low dietary fiber. Because too much fat in the body will promote the synthesis of some hormones, form an imbalance between hormones, and lead to an increase in hormone levels in the breast.
Dietary fiber and human health
Dietary fiber refers to the sum of edible plant components, carbohydrates and similar substances that can resist digestion and absorption of human small intestine and can be fermented partially or completely in human large intestine, including polysaccharides, oligosaccharides, lignin and related plant substances. In daily life, people tend to confuse dietary fiber, crude fiber and cellulose. Crude fiber is only a part of dietary fiber, which refers to the residue left by plant tissues after being treated with a certain concentration of acid, alkali, alcohol, ether and other reagents for a certain period of time at a certain temperature. Its main components are cellulose and lignin. Cellulose is only a part of crude fiber, which is a single compound and a linear compound with glucose linked by β- 1 4 glycosidic bond. It can be seen that the amount of dietary fiber is more than crude fiber and cellulose. Crude fiber is the most common component in dietary fiber, and cellulose is the main component of dietary fiber.
Physiological Function of Dietary Fiber Although dietary fiber cannot be digested and absorbed by human body, it plays an important physiological role in the body and is an essential nutrient for maintaining human health. Dietary fiber is known as "intestinal cleaner" because of its outstanding role in preventing gastrointestinal diseases and maintaining gastrointestinal health. 1) The water absorption and swelling properties of dietary fiber are beneficial to increase the volume of chyme, stimulate the peristalsis of gastrointestinal tract, soften feces, prevent constipation, promote defecation and increase defecation times, play a role in drainage, reduce the retention time of feces in intestinal tract and the contact between harmful substances in feces and intestinal tract, and keep intestinal tract clean, thus reducing and preventing gastrointestinal diseases. 2) Dietary fiber can inhibit the absorption of cholesterol and prevent hyperlipidemia and hypertension. 3) Dietary fiber can delay and reduce the absorption of harmful substances such as heavy metals, and alleviate and prevent the toxic effects of harmful chemicals on human body. 4) Dietary fiber can improve intestinal flora, maintain microecological balance in vivo, and is beneficial to the synthesis of some nutrients. 5) Water-soluble dietary fiber has a strong water absorption and expansion performance, which expands after water absorption, and its volume and weight increase by/kloc-0 ~15 times, which can not only increase people's satiety, but also reduce the absorption of fat in food, reduce the calorie ratio of fat in diet, relatively control and reduce the total dietary energy, and avoid excessive accumulation of fat in the body caused by excessive heat energy, which can not only solve the problem of satiety, but also achieve the goal of. 6) Scientific research has found that soluble dietary fiber has the best effect in controlling the sharp rise of postprandial blood sugar and improving glucose tolerance. Dietary fiber can delay the absorption of glucose, delay the digestion of digestible sugars such as starch, avoid the sharp rise of postprandial blood sugar, enhance the sensitivity of dietary fiber to insulin, directly affect the function of islet A cells, improve the regulation of insulin in blood, improve the degree of glucose tolerance of human body, and be beneficial to the treatment and rehabilitation of diabetes. Studies have shown that a diet with sufficient dietary fiber content has special effects in preventing and treating diabetes.