Generally speaking, we say that the role of tea:
1. Excite and refresh, reduce fatigue, sleep less and think better.
The refreshing effect of tea is mainly due to the effect of purine alkaloids such as caffeine, theanine and theobromine in tea, which is not affected by other factors and reduces the effect. Drinking tea excites the nerves. The excitability caused by drinking and smoking can improve people's basic metabolism, muscle contraction, lung ventilation, blood outflow and gastric juice secretion. The latter can weaken the excitability caused by inhibitory conditioned reflex, and when it is excessive, it will cause anesthesia poisoning to the central nervous system, which is unhealthy. Therefore, in daily life, people drink a cup of tea when they feel tired, which stimulates the brain central nervous system with declining function, making it change from dull to excited, concentrate on thinking, and achieve the effect of excitement and brainstorming.
2. diuresis, enhance the excretion function of the kidney.
Mainly because tea soup contains purine compounds such as caffeine, theanine and theobromine. This effect is stronger than caffeine, and caffeine is stronger than theobromine. The results of clinical trials show that theanine has the greatest diuretic effect, but theobromine has the longest diuretic effect. The main function of these components is to inhibit the reabsorption of renal tubules and increase the content of sodium ions and nitrogen ions in urine. These compounds directly relax the renal blood vessels by exciting the blood movement center, thus enhancing the blood flow of the kidney and the filtration rate of the glomerulus. In addition, there are aromatic oils such as flavonoids, glycosides and quercetin in tea soup, which also have diuretic effect.
3. Stop dysentery and prevent constipation.
Clinical trials show that the effect of green tea in treating dysentery is better and more lasting than other expensive chemical drugs. There are many kinds of constipation, such as habitual constipation, neurotic constipation, dystrophic constipation and delayed constipation. Constipation is caused by intestinal relaxation, which weakens intestinal peristalsis. The astringency of tea polyphenols in tea enhances intestinal peristalsis, so tea has the effect of treating constipation. In addition, the trace tea saponin in tea can also promote intestinal peristalsis and treat chronic constipation.
4. The function of preventing dental caries and removing halitosis.
Tea tree is a plant that can enrich fluorine from soil. The fluorine content of old leaves is higher than that of young leaves. The caries prevention mechanism of tea tree is mainly because it is rich in fluorine. In addition, tea polyphenols in tea can kill lactic acid bacteria and their cariogenic bacteria. These fungi are pathogens that directly or indirectly cause tooth decay. The surface activity of saponin in tea enhances the bactericidal effect of fluoride and tea polyphenols. Therefore, the anti-caries effect of tea is mainly due to the comprehensive effect of these three compounds. Moreover, the research shows that the caries prevention effect of tea is far better than that of fluoride compound preparation. In addition, tea also has the functions of strengthening tooth resistance, eliminating residual protein in oral cavity and removing halitosis.
5. Help digestion, promote food absorption and normal metabolism.
Caffeine and flavanol in tea can enhance the peristalsis of digestive tract, so it is also helpful to digest food and prevent digestive organ diseases. Caffeine has a great influence on fat metabolism. Tea soup contains vitamin compounds such as inositol, folic acid and 6,8-lipoic acid, as well as "lipophilic factors" and "anti-fat substances" such as methionine, cysteine, lecithin and choline, which also have the function of regulating fat metabolism. Tea not only helps digestion, but also has the effect of bleeding from gastric ulcer. This is because the polyphenols in tea can attach to the wound in the stomach in the form of a thin film, thus playing a protective role. Tea also has the ability to absorb harmful substances, which can not only "purify" microorganisms in digestive tract organs, but also carry out unique chemical purification on stomach, kidney and part of liver.
6. It can improve eyesight and treat eye diseases.
Tea contains original VA, namely carotene. Each gram of tea contains about 54.6ug of carotene, which is equivalent to about 965,438+0 international units of VA, and also contains β-ionone, which is also the biosynthesis precursor of VA and carotene. The content of carotene in tea is higher than that in general food, and it is second only to pepper and alfalfa in plant food. Carotene can prevent the increase of keratinization of epithelial tissue, prevent keratinization of lacrimal gland cells caused by keratinization, degeneration and proliferation, and stop the secretion of tears to form dry eye. In addition, after carotene is converted into VA in vivo, rhodopsin can be synthesized with protein in retina, which can enhance the photosensitive ability of retina and treat and prevent night blindness. Tea also contains VB2, which can treat diseases at the junction of eyes and mucosa, such as keratitis. VC in tea can improve the body's resistance to infectious diseases and also play a certain role in preventing cataract and lens opacity.
7. It can prevent scurvy and treat vitamin C deficiency.
Tea is rich in VC. Every 100g of green tea contains VC 180mg of VC, which is similar to strawberry. Lack of VC will destroy the permeability of blood vessel wall, causing petechial hemorrhage, dental caries hemorrhage, serous cavity hemorrhage of muscle and joint capsule and so on. Lack of VC will reduce the body's resistance to infectious diseases, hinder the normal healing of wounds, cause gingival lesions, fragile tissues, and easily lead to periosteum division, fracture and dental caries. Tea soup contains a variety of flavonoids, which has an important synergistic effect on the treatment of scurvy and VC, and can help the body absorb VC and enhance the toughness of microvessels. In order to supplement the lack of VC in food, tea has become an indispensable drink for people in remote ethnic minority areas such as Inner Mongolia, Xinjiang and Tibet.
8. It can quench thirst, relieve fever and relieve summer heat.
It is the multifunction of tea. Tea soup not only supplements water to maintain the normal metabolism of the body, but also contains ingredients with cooling, antipyretic and body fluid production functions. For example, caffeine can selectively excite the cerebral cortex at a low dose, which plays an important role in controlling and regulating the temperature center of hypothalamus. There are polyphenols in tea soup, which can slightly stimulate the oral mucosa and produce a fresh and refreshing taste. Promote saliva secretion, produce fluid in the mouth, and stop thirst. In addition, tea soup also contains aromatic substances, organic acids and so on. These substances are volatile and play an endothermic role in their volatilization process, so they are important coolants. Therefore, from two aspects of specimens, tea regulates body temperature and plays a fundamental role in relieving fever and quenching thirst.
9. Anti-aging effect.
Lipid peroxidation in human body is one of the mechanisms of human aging, so people can take some antioxidant compounds, such as VC and VE, to enhance their resistance and delay aging. The catechin in tea has obvious antioxidant activity, and its activity intensity exceeds that of VC and ve.
10. Reduce the harm of smoking to human health.
Smoking is harmful to human body, so for the health of individuals and others, we should try to smoke less or not. Because passive smoking is also very harmful. Nicotine in cigarettes will increase the secretion of hormones that promote vasoconstriction, and the result of vasoconstriction will affect blood circulation, reduce the supply of oxygen, and lead to an increase in blood pressure. Smoking too much will also accelerate arteriosclerosis and the decrease of VC in the body, and accelerate human aging. Tea is rich in VC, polyphenols and oxolinic acid, which has a certain protective effect on the body and can also reduce the toxicity of cigarettes.
1 1. Anti-inflammatory and bactericidal.
Catechins in tea have obvious inhibitory effects on typhoid Bacillus, paratyphoid Bacillus, Staphylococcus aureus, Staphylococcus aureus and dysentery. Flavonoids and alcohols in tea can promote the activity of small renal glands, and the increase of small renal glands can reduce the permeability of capillaries and reduce blood exudation, and at the same time have a good antagonistic effect on histamine, which belongs to hormone anti-inflammatory effect. Tea flavonol compounds themselves also have direct anti-inflammatory effects. Therefore, in ancient times, people in China used tea juice to treat wounds to prevent them from becoming inflamed.
12. Reduce alcohol toxicity and sober up.
Alcohol is mainly hydrolyzed into water and carbon dioxide by the action of alcohol hydrolase in human liver. In this hydrolysis process, vitamin C is needed as a catalyst. If vitamin C in the body is insufficient, the detoxification effect of the liver will be weakened, and there may be the possibility of alcoholism. Smoking while drinking will make you drunk, because VC content is too low.
It is found that drinking a small amount of tea after drinking can supplement VC on the one hand, and caffeine in tea has diuretic effect on the other hand, which can make alcohol excreted quickly. In addition, tea can also stimulate the central nervous system of cerebral palsy, effectively promote metabolism, and then play a role in sobering up. However, some scholars think that drinking tea is not appropriate. They think that tea can excite the nerve center, and drinking strong tea after drunkenness will increase the burden on the heart. Tea has diuretic effect, so that the toxic hexanal in alcohol is discharged from the kidney without decomposition, which is too irritating to the kidney and harmful to health. I think the above two viewpoints have their own mechanisms. Don't drink a lot of strong tea after drinking, especially those with weak heart and kidney function. Generally, eating more fruit or drinking a small amount of tea after drinking is beneficial to sober up, and drinking too much tea is not desirable.
13. Detoxification of heavy metal poisoning.
One of the negative effects of modern industrial development is the appearance of environmental pollution. The content of various heavy metals (such as copper, lead, mercury, cadmium, chromium, etc.) is very high. ) is one of them in food and drinking water. These heavy metals are high in content and have obvious toxic effects on human health. Experiments show that tea polyphenols in tea have a strong adsorption effect on heavy metals, and have a very thorough adsorption effect on heavy metals such as silver, cadmium, cobalt, copper, nickel and lead in water, so drinking tea often will be beneficial to health.
14. It can treat hypertension, reduce blood lipid, inhibit arteriosclerosis, and prevent and treat coronary heart disease.
Clinical experiments show that the prevalence of coronary heart disease in tea drinkers is significantly lower than that in non-tea drinkers or occasional tea drinkers. Drinking tea is effective for patients with hypertension, and green tea is better than black tea. Polyphenols, vitamins and amino acids in tea play an important role in human fat metabolism. Disorder of fat metabolism is usually an important cause of atherosclerosis in patients with liver disease. Polyphenols in tea, especially catechins, can prevent the accumulation of cholesterol, other enols and neutral fats in blood and liver, and prevent arteriosclerosis in arteries and liver. Phytosterols in tea, such as VC, CB 1, VB2, inositol, methionine, folic acid, 6,8-lipoic acid, etc., can also reduce cholesterol and prevent atherosclerosis.
15. Lowering blood sugar, treating diabetes and regulating carbohydrate metabolism.
Diabetes mellitus is a group of metabolic endocrine diseases characterized by hyperglycemia. It is the metabolic disorder of sugar, fat and protein caused by insulin deficiency and hyperglycemia. Clinical experiments show that drinking tea can reduce or completely eliminate urine sugar for patients with moderate and mild chronic diabetes, and reduce urine sugar for severe patients, obviously alleviating various main symptoms. After drinking tea, the symptoms of thirst are relieved, the frequency of urination in the middle of the night is reduced, and the urine sugar is reduced or disappeared. The important reason why drinking tea can treat diabetes is that tea contains polyphenols. These substances can maintain the normal toughness of microvessels and control the permeability of microvessels, so they can restore the normal toughness of microvessels in diabetic patients with fragile microvessels and have an effect on treating diabetes. In addition, VC, methyl salicylate, VB, pantothenic acid and 6,8-lipoic acid are all important substances beneficial to sugar metabolism.
16. Radiation protection, radiation protection.
1945, the United States bombed Hiroshima, Japan with atomic bombs, causing unprecedented mass casualties in history. Through interviews and understanding of the victims, it is found that the radiation damage of long-term tea drinkers is generally light and the survival rate is high. The reason why tea can resist radiation damage is mainly because it contains a variety of catechins. According to experiments, catechin has therapeutic effect on radiation injury in vivo, and it can absorb radioactive substance Sr90. Even if Sr90 goes deep into animal bone marrow, taking catechin can gradually eliminate it. In addition, tea also contains anti-radiation substances such as ester polysaccharide, cysteine derivative glutathione and ascorbic acid. Therefore, the anti-radiation properties of polyphenols such as catechins and ester polysaccharides have been recognized by most scholars.
17. anticancer and antimutagenic effects.
Cancer is one of the difficult problems in the current medical field. Most of them are changes in genetic material. Generally, normal genes are changed into oncogenes by carcinogens, and then the oncogenes are expressed under the influence of other substances, causing protein and abnormal cell division and differentiation into cancer cells. Mutation refers to the change of genetic material, including chromosome change and genetic material (gene) change. Since the late 1970s, scientists all over the world have done a lot of research on this issue. Studies in mice, rats, rabbits and other living animals show that tea extracts have obvious inhibitory effects on cancers such as skin cancer and lung cancer caused by carcinogens such as ultraviolet rays, TPA, benzopyrazine, 7, 12- dimethylbenzoanthracene, 3-methylcholanthrene and N- methyl -N- nitrosourea.
Since 1980s, the research on tea medicines at home and abroad can be summarized as follows: inhibiting the formation of final carcinogens, regulating the metabolic process of protocarcinogens, interacting directly with the metabolites of electrophilic final carcinogens, inhibiting oncogenes and DNA***, and scavenging free radicals.
Recent research reports show that green tea can prevent skin cancer: mainly because tea polyphenols, an antioxidant in tea, can kill tumor cells and "starve" cancer by limiting the growth of blood vessels around tumors. The content of tea polyphenols in green tea is the highest among many teas, and drinking 4-5 cups of green tea every day can play a very good preventive role.
It is generally believed that green tea has the highest anticancer and mutation resistance, followed by pressed tea, scented tea, oolong tea and black tea. West Lake Longjing is the best green tea. Wuyi rock tea in oolong tea is comparable to Longjing tea.
18. Others.
With the progress of medical science and technology, the effect of tea on human body is gradually developing. Tea can also be used as drugs for preventing gallstones, kidney calculi's disease and bladder stones, treating bronchitis and colds, improving respiratory function, preventing gout, eliminating the accumulation of harmful salts and toxins in human body, treating epilepsy, and preventing and treating various vitamin deficiencies. It can also be used as a source of copper and iron in human body, and can treat anemia caused by long-term iron deficiency in food. In addition, green tea in tea also has a certain effect on treating leukemia and AIDS, mainly because epicatechin in tea can slow down the reproduction of leukemia virus and human immunodeficiency virus (causing AIDS).