The effect of dietary fiber on the human body

Cellulose is one of the most widely distributed and abundant polysaccharides in nature. It is the main structural component of plant cell walls and is usually combined with hemicellulose, pectin, and lignin in a way and to a degree that greatly influences the texture of foods of plant origin. In contrast, changes in the texture of plants at maturity and post-ripening are caused by changes in pectin substances.

I. Dietary fiber

Fiber is an important dietary fiber. Food fiber includes crude fiber, semi-crude fiber, and lignin.

Many types of high-purity dietary fiber extracted from natural foods (konjac, oats, buckwheat, apples, cactus, carrots, etc.) are generally used.

Human dietary fiber is mainly contained in vegetables and roughly processed cereals, which cannot be digested and absorbed, but has functions such as promoting intestinal peristalsis and facilitating fecal excretion.

Herbivores rely on symbiotic microorganisms in their digestive tract to break down cellulose so that it can be absorbed and used.

Second, the fiber-rich food

Although fiber can not be absorbed by the body, but has a good intestinal cleansing effect, and is suitable for IBS (irritable bowel syndrome) patients to eat healthy food.

The fiber content of common foods is as follows.

Wheat bran: 31%.

Grains: 4-10%, in descending order of wheat grain, barley, corn, buckwheat flour, barley flour, sorghum rice, and black rice.

Cereals: 8-9%.

Oatmeal: 5-6%

Potatoes, white potatoes, and other yams have about 3% fiber content.

Legumes: 6-15%, listed from most to least as soybeans, green beans, fava beans, kidney beans, peas, black beans, red pinto beans, and green beans.

Vegetables: bamboo shoots have the highest content, with dried bamboo shoots containing 30-40% cellulose and peppers over 40%.

The rest contains more fiber: fern, cauliflower, spinach, pumpkin, cabbage, and rape.

Mushrooms (dried): the highest cellulose content, including matsutake mushrooms with cellulose content close to 50%, more than 30% according to the ranking from most to least: hair mushroom, shiitake mushroom, silver fungus, wood ear. In addition, the fiber content of nori is also high, reaching 20%.

Nuts: 3-14%. 10% or more are: black sesame seeds, pine nuts, and almonds; below 10% are white sesame seeds, walnuts, hazelnuts, pecans, sunflower seeds, watermelon seeds, and peanut kernels.

Fruits: the most content is dried red fruits, with nearly 50% fiber content, followed by dried mulberries, cherries, sour dates, black dates, dates, small dates, pomegranates, apples, and duck pears.

Whether it is cereals, potatoes, or beans, generally speaking, the finer the processing, the less fiber content.

Various types of meat, eggs, dairy products, various oils, seafood, alcoholic beverages, and soft drinks do not contain fiber; the fiber content of various baby foods is extremely low.

Third, the intake of fiber

Foods without fiber include: chicken, duck, fish, meat, eggs, etc.; foods with a lot of fiber include: coarse grains, bran, vegetables, fruits, lentils, broad beans, and other legumes that are rich in fiber. Therefore, it is recommended that diabetic patients consume more fiber-rich foods such as beans and fresh vegetables as appropriate. At present, domestic plant fiber food, mostly made of rice bran, bran, wheat dregs, beet crumbs, pumpkin, corn peel and seaweed plants, etc., has a certain effect on reducing blood sugar and blood lipids.

⒈ physiological effects

The human digestive tract does not exist cellulase, which can not be decomposed and used as cellulose, food cellulose is a substance that is not easily digested and absorbed, in the past, it is considered "waste", but now it is considered to have an important role in protecting human health, prolonging life. Therefore, it is called the seventh nutrient.

The main physiological role of fiber is to absorb large amounts of water, increase the number of feces, promote intestinal peristalsis, speed up the excretion of feces, shorten the residence time of carcinogenic substances in the intestinal tract, and reduce the adverse stimulation of the intestinal tract, thus preventing the occurrence of intestinal cancer.

①It helps E. coli in the intestine to synthesize many kinds of vitamins.

②The small specific gravity and a large volume of cellulose occupy more space in the gastrointestinal tract, which makes people feel full and is good for weight loss.

③The large volume of fiber can stimulate the gastrointestinal tract after eating, resulting in increased secretion of digestive juices and enhanced peristalsis of the gastrointestinal tract, which can prevent and control constipation in diabetes.

④High fiber diet can slow down the absorption of sugar by delaying gastric emptying, changing intestinal transit time, and forming a gel of soluble fiber in the intestine. It can also enhance glucose metabolism by reducing the secretion of intestinal hormones such as gastrin or glucagon, reducing stimulation of pancreatic B cells, reducing insulin release, and increasing the sensitivity of peripheral insulin receptors.

⑤ High-fiber diet can increase insulin receptor binding on monocytes in type I diabetic patients, thus saving insulin requirement. Therefore, diabetic patients eating a high-fiber diet can not only improve hyperglycemia, reduce the application dose of insulin and oral hypoglycemic drugs, is conducive to weight loss, and can also prevent and control constipation, hemorrhoids, and other diseases.

⒉ Fiber and physical health

Not all carbohydrates can be digested and converted into glucose. The carbohydrates that are difficult to digest are called fiber. It is an integral part of a healthy diet, and fiber (i.e., dietary fiber) in food plays an important role in human health. Eating foods high in fiber can reduce the likelihood of bowel cancer, diabetes and diverticular disease. It is also less likely to cause constipation.

Fiber is often thought of as "coarse grass," but this is not the case, as fiber absorbs water. Therefore, it can make food residues swell and loosen up, making it easier to pass through the digestive tract.

The risk of infection is reduced because the residue stays in the body for a shorter period; also, when some foods, especially meat, are spoiled, they can produce carcinogens and cause cellular mutations, and the reduced residence time of the residue in the body reduces the likelihood of this.

Regular meat eaters have a diet low in fiber, which increases the time food spends in the intestine to 24-72 hours, during which time some foods may spoil. So if you like to eat meat, then you must make sure that your diet also contains a lot of fiber.

There are many types of fiber, some of which are proteins rather than carbohydrates.

Some types of fiber, such as those found in oats, are called "soluble fiber," and they combine with sugar molecules to slow the absorption of carbohydrates. In this way, they ca,n help keep blood sugar levels stable.

Some fibers are much more absorbent than other types of fibers. Wheat fiber can swell up to 10 times its original volume in water, while the glucomannan fiber in Japanese konjac can swell up to 100 times its original volume in water.

Because fiber expands food and slows the release of energy from sugars, highly absorbent fiber can help control appetite and help maintain proper weight.

The ideal intake of fiber is no less than 35 grams per day. With proper food choices, it is easy to meet this standard without the need for additional supplementation.

In summary, it is best to obtain fiber from a large variety of food sources, including oats, lentils, fava beans, plant seeds, fruits, and raw or lightly cooked vegetables. Most of the fiber in vegetables is destroyed during the cooking process, so vegetables are best eaten raw.

ðŸ™' The main functions of dietary fiber

(1) Treatment of diabetes

A high-fiber diet not only reduces the intake of sugar but also regulates insulin secretion so that blood sugar and insulin maintain a normal physiological requirement. Diabetes is a common endocrine metabolic disorder, which is a widespread metabolic disorder caused by the absolute or relative insufficiency of insulin secreted by the human pancreas, mainly because sugar cannot be used by the body and is excreted from the urine. Food cellulose can form a gel due to water absorption, slowing down the absorption of glucose and cholesterol by the intestinal mucosa, slowing down the rise of blood sugar, reducing the need for insulin, and maintaining a more desirable level of blood sugar and insulin. The fiber in food can also increase the feeling of satiety and control the intake of sugary foods, which is conducive to alleviating diabetes.

(2) Prevention of atherosclerosis

One of the causes of atherosclerosis is the increase in cholesterol content in the blood. More cholesterol is deposited in the inner wall of blood vessels, which makes the inner wall of blood vessels thicker and the diameter thinner, affecting blood flow and reducing the toughness and elasticity of blood vessels, thus causing coronary heart disease, hypertension and other diseases. The discharge of cholesterol and bile acid has an extremely close relationship with dietary fiber. The fiber in vegetables and fruits can not only inhibit the absorption of cholesterol in the intestine but also combine with the metabolites of cholesterol into steroid substances that cannot be absorbed by the body, accelerating the metabolism and excretion of cholesterol and significantly reducing the cholesterol content in the serum. At this time, adding 20% of fiber to their normal diet, dietary fiber can combine with bile acids, and the cholesterol in the blood drops significantly, and the amount of bile acid excretion also increases. At the same time, the combination of dietary fiber and bile acids results in the conversion of cholesterol to bile acids, thus reducing the cholesterol level. Therefore, eating more fiber-rich vegetables and fruits can effectively prevent the hardening of blood vessels and help prevent the occurrence and deterioration of coronary heart disease and hypertension.

(3) Anti-hypertensive effect

Dietary fiber can adsorb ions and exchange with sodium and potassium ions in the intestine, thus lowering the sodium-potassium ratio in the blood, thus having a blood pressure-lowering effect.

(4) Anti-cancer effect

Since the seventies, there has been an increasing number of reports on the research of dietary fiber in anti-cancer, especially the relationship between dietary fiber and digestive tract cancer. Early investigations in India showed that people living in the north of India consumed significantly more dietary fiber than in the south, and the incidence of colon cancer was significantly lower than in the south. Based on this finding, scientists have done more in-depth research and found that there are several reasons why dietary fiber is associated with the prevention and treatment of colon cancer:

Some saprophytic bacteria in the colon can produce carcinogenic substances, while some beneficial microorganisms in the intestine can use dietary fiber to produce short-chain fatty acids, which can inhibit the growth of saprophytic bacteria; bile acid and goosebile acid in bile can be metabolized by bacteria as cellular carcinogens and mutagens, and dietary fiber can bind bile acid and other substances and expel them from the body to prevent the production of these carcinogens; dietary fiber can promote intestinal peristalsis, increase the volume of feces and shorten the time of evacuation, thus reducing the chance of contact between carcinogens in food and colon; beneficial bacteria in the intestine can use dietary fiber to produce butyric acid, which can inhibit the growth and proliferation of tumor cells, induce the transformation of tumor cells to normal cells and control the expression of carcinogenic genes.

(5) Weight loss and treatment of obesity

Dietary fiber replaces a portion of the number of nutrients in food while reducing the total food intake. Dietary fiber promotes increased secretion of saliva and digestive juices and acts as a filler for the stomach while absorbing water and swelling to produce a feeling of satiety and suppress the desire to eat. Dietary fiber binds to some of the fatty acids, and this binding makes it impossible for the fatty acids to be absorbed when they pass through the digestive tract, thus reducing the rate of fat absorption.

(6) Treatment of constipation

Dietary fiber has a strong water-holding capacity, and its water absorption rate is up to 10 times higher. When it absorbs water, it increases the volume of intestinal contents, loosens and softens the stool, and makes it pass through the intestine more smoothly and with less effort. At the same time, dietary fiber as intestinal foreign matter can stimulate intestinal contraction and peristalsis, speeding up the excretion of stool, and playing a role in the treatment of constipation.

However, there are two sides to everything in the world, and dietary fiber is no exception.

Excessive intake of dietary fiber will certainly affect human health, there is no doubt about it. For example, it affects the digestion and absorption of proteins and other nutrients in the body and can cause abdominal discomfort; it increases the peristalsis and gas production in the intestines and reduces the absorption of nutrients. For people with gastritis and other digestive disorders, excessive consumption of fiber will bring more irritation and aggravate the condition. At the same time, all kinds of fiber can inhibit the activity of pancreatic enzymes and also reduce some enzymes in the small intestine, such as those that break down triglycerides, starch, and protein. The reduction of digestive enzymes will affect the digestion and absorption of food in the small intestine to some extent. Therefore, there is a limit to everything in moderation.