1, refreshing: Caffeine in black tea can stimulate the exciting nerve center of cerebral cortex, thus refreshing, making the thinking reaction more acute and enhancing memory; Black tea also has an exciting effect on the vascular system and the heart, accelerating blood circulation to promote metabolism. At the same time, black tea can promote sweating and diuresis, thus reducing fatigue.
2, shengjin Qingre: Drinking black tea in summer can quench thirst and relieve summer heat. Polyphenols, sugars, amino acids and pectin in black tea react with saliva to stimulate saliva secretion and moisten the mouth; At the same time, caffeine can regulate body temperature and maintain physiological balance in the body.
3. Diuretion: Under the combined action of caffeine and aromatic substances in black tea, it can increase the blood flow of the kidney, improve the glomerular filtration rate, expand the renal microvasculature, inhibit the reabsorption of water by renal tubules, and promote the increase of urine volume.
4、? Strengthening bone: Polyphenols in black tea can inhibit the activity of destroying bone cells and play a role in strengthening bone.
There are many places to pay attention to when drinking tea. For example, tea contains a lot of tannic acid, theophylline, tea sesame oil and various vitamins, so it is more suitable to brew with water of about 80 degrees. If the tea leaves are soaked in high-temperature water for a long time in a thermos cup, just like decocting in micro water, all the vitamins in the tea leaves are destroyed, a large amount of tea sesame oil is volatilized, and a large amount of tannic acid and theophylline are oozing out. This not only reduces the nutritional value and fragrance of tea, but also increases harmful substances.