21. What are the main nutritional functions and medicinal components of tea?
Tea contains over 300 chemical components with nutritional and health care functions. The main nutrients include: protein, amino acids, fats, carbohydrates, minerals, trace elements, and vitamins; there are more than 10 types of vitamins, most of which can dissolve in water during brewing and be fully utilized. Additionally, tea contains efficacy components with various functions, such as tea polyphenols, caffeine, and lipopolysaccharides. These form the material basis for tea's high nutritional value and efficacy. Regular and appropriate consumption of tea will be greatly beneficial to human health.
22. Why does drinking tea quench thirst?
After tea is brewed with hot water, chemical components in the tea soup, such as polyphenols, sugars, amino acids, pectin, and vitamins, react with saliva in the mouth, moisturizing the oral cavity. Therefore, drinking tea can quench thirst.
23. Why does drinking tea refresh the mind?
Drinking tea has a stimulating effect on the human central nervous system, primarily produced by its xanthine derivatives, caffeine, and theophylline. The caffeine and aromatic substances in tea are stimulants that excite the central nervous system. Research suggests that while both tea and coffee can refresh the mind, drinking coffee may lead to arteriosclerosis, whereas tea can inhibit arteriosclerosis. This is because tea contains relatively more tea polyphenols and vitamin C, which can effectively counteract the adverse effects of caffeine.
24. Why does drinking tea improve eyesight?
Tea contains a vast wealth of vitamins. Research indicates that vitamin C, vitamin B2, and vitamin E play certain roles in improving acuity and eyesight. Vitamin C and vitamin B2 are effective in preventing cataracts; vitamin A can participate in the regeneration of rhodopsin in the rod cells of the retina, thereby maintaining normal visual function. Washing the eyes with a tea decoction can treat ulcerative blepharitis, and washing eyes with tea can also treat acute conjunctivitis and other eye diseases. The carotene contained in tea can be converted into vitamin A in the human body. Therefore, drinking tea, especially green tea, can help improve eyesight.
25. Why does drinking tea help with weight loss?
Drinking tea has the functions of lowering blood lipids and weight loss/body shaping. China's Tang Dynasty "Compendium of Materia Medica" records that "Tea, consumed over time, makes one lean and removes human fat." This shows our ancestors long ago discovered tea's weight loss effect. Human obesity is mainly due to the deposition of excess fatty substances under the skin and around internal organs. Substances in tea such as caffeine, flavanols, and vitamins can promote fat oxidation and remove excess body fat. Therefore, drinking more tea can achieve weight loss effects.
26. Why does drinking tea prevent hypertension?
Tea contains active substances like tea polyphenols and catechins, which can maintain vascular elasticity, eliminate arterial vasospasm, and prevent blood vessel rupture. Furthermore, these active substances can also relax blood vessel walls, increase the effective diameter of blood vessels, and achieve blood pressure reduction through vasodilation. Therefore, regular and moderate tea consumption can prevent the occurrence of hypertension. If one already has hypertension, drinking tea also promotes fat metabolism and prevents arteriosclerosis.
27. Why does drinking tea have a diuretic effect?
Both drinking more plain water and drinking more tea can increase urine output, but their diuretic functions are entirely different. This is because tea soup contains caffeine, which increases the伸缩 function of muscle activity, stimulates the spinal cord, causes kidney contraction, and promotes an increase in the total excretion of urea, uric acid, and salts, thereby producing a diuretic effect. Tea has a relatively good diuretic effect; compared to an equal volume of water, tea is 1.55 times higher, and chloride excretion is 2.5 times that of water.
28. Why does drinking tea aid digestion?
According to expert research results, caffeine in tea has a moderating digestive effect on nitrogen-containing compounds in food, especially proteins, preventing waste and providing lasting resistance to hunger. Caffeine can increase gastric gland secretion, thus promoting appetite and aiding digestion; flavanol compounds can also enhance digestive tract motility, thereby helping food digestion and preventing digestive system diseases.
29. Why does drinking tea prevent cancer?
Tea polyphenols in tea can inhibit or block multiple carcinogenic components, such as vitamin C, vitamin E, lipopolysaccharides, selenium, and zinc. Research results show that the anti-cancer effect of tea is the result of the synergistic action of various anti-cancer components, primarily tea polyphenols. In terms of effectiveness, green tea is the best, although every type of tea has anti-cancer effects. Therefore, having a cup of tea after a meal is beneficial for the body.
30. Why does drinking tea sterilize and reduce inflammation?
Tea contains various sterilizing components. Modern research has found that among them, alcohols, aldehydes, esters, phenols, and other organic compounds all have bactericidal effects, but their mechanisms of action are not entirely the same; some interfere with bacterial metabolism, while others cause denaturation of bacterial proteins. Furthermore, organic compounds in tea such as sulfur, iodine, chlorine, and chlorides also have sterilizing and anti-inflammatory effects. Most of these substances are water-soluble and can be infused into the tea soup, hence drinking tea has sterilizing functions.
(Edited and organized: Mao Xianxian)