The main effect of black tea.

The caffeine in black tea excites the nerve center by stimulating the cerebral cortex, promoting refreshment and concentration of thinking, which in turn makes the thinking reaction sharper and memory enhanced; it also has an excitatory effect on the vascular system and the heart, strengthens the heartbeat, and accelerates blood circulation. 

In order to facilitate metabolism, it also promotes sweating and diuresis, thereby accelerating the excretion of lactic acid (a substance that makes muscles feel fatigued) and other old waste substances in the body to achieve the effect of eliminating fatigue.

Under the combined action of caffeine and aromatic substances in black tea, the blood flow of the kidneys is increased, the glomerular filtration rate is increased, the renal microvessels are expanded, and the reabsorption of water by the renal tubules is inhibited, thus contributing to the increase of urine output. 

This is beneficial to eliminate lactic acid, uric acid (related to gout), excessive salt (related to high blood pressure), harmful substances, etc. in the body, as well as to relieve edema caused by heart disease or nephritis.

On May 13, 2002, the American Medical Association published a survey of 497 men and 540 women for more than 10 years, pointing out that people who drink black tea have strong bones, and the polyphenols in black tea (also found in green tea) have the ability to inhibit the destruction of bone cell substances. 

In order to prevent and treat common osteoporosis in women, it is recommended to take a small cup of black tea every day for several years. For example, adding lemon to black tea can strengthen bones and have a stronger effect. Various fruits can also be added to black tea, which can play a synergistic effect.

Over the past 5 years, the U.S. government has funded more than 150 studies on green and black teas and their chemical constituents, which have shown that the antioxidants in green and black tea can completely disrupt the pathways of chemicals in cancer cells. 

"Black tea is about as effective as green tea, but black tea's antioxidants are much more complex than green tea, especially for the heart," said Dr. Murray Mittelman, director of cardiovascular epidemiology at Beth Israel Deaconess Medical Center in Boston. . American magazine reported that black tea has stronger anti-aging effects than garlic, broccoli and carrots.

When people drink green tea without a meal, they will feel uncomfortable in the stomach. This is because the important substances contained in tea, tea polyphenols, have astringent properties and have a certain stimulating effect on the stomach. powerful. 

And black tea is different. It is fermented and baked. Black tea not only does not hurt the stomach, but can nourish the stomach. Regular consumption of black tea with sugar and milk can reduce inflammation, protect the gastric mucosa, and also have a certain effect on the treatment of ulcers.

A study in the American medical community is related to black tea. The study found that heart patients who drink 4 cups of black tea a day can increase vasodilation from 6% to 10%. Ordinary people after stimulation, the relaxation rate will increase by 13%.