The effects of black tea:

1, refreshing fatigue: medical experiments have found that the caffeine in black tea by stimulating the cerebral cortex to stimulate the nerve center, contributing to the refreshing, thinking power to focus on the mind to make thinking more responsive, memory enhancement.

2, the heat: summer drinking black tea can quench the thirst of summer, because the tea polyphenols, carbohydrates, amino acids, pectin and other chemical reactions with the saliva, and stimulate the secretion of saliva, resulting in the mouth to feel moisturized, and produce a sense of coolness; at the same time, the caffeine control of the hypothalamus of the thermo-centers, regulating body temperature, it also stimulates the kidneys to promote the heat and the excretion of dirt, to maintain the physiological balance of the body.

3, diuretic: in the black tea caffeine and aromatic substances in the joint effect, increase renal blood flow, improve glomerular filtration rate, dilate the renal microvessels, and inhibit renal tubular water reabsorption, which contributes to the increase in urine output. This is conducive to the elimination of lactic acid, uric acid (related to gout), excessive salt (related to high blood pressure), harmful substances, etc., as well as easing the edema caused by heart disease or nephritis.

4, anti-inflammatory sterilization: black tea in the polyphenolic compounds with anti-inflammatory effect, and then by the experimental discovery of catechins can be combined with unicellular bacteria, so that the protein coagulation precipitation, so as to inhibit and eliminate pathogenic bacteria. So bacillary dysentery and food poisoning patients drink black tea is quite beneficial, folk also commonly used strong tea coated wounds, bedsores and athlete's foot.

5, detoxification: according to experimental evidence, black tea in the the tea alkaloids can adsorb heavy metals and alkaloids, and precipitation decomposition, which is industrial pollution of drinking water and food for modern people, is not less than a gospel.

6, anti-aging: In the past five years, the U.S. government has funded more than 150 studies on green and black tea and its chemical components, and the results show that the antioxidants in green and black tea can completely destroy the path of the spread of chemicals in cancer cells.

7, stomach and stomach: people drink green tea when not eating will feel uncomfortable stomach, this is because the tea contains important substances - tea polyphenols have astringent, on the stomach has a certain stimulating effect, in the case of fasting the stimulation is stronger. Black tea is different. It is fermented and baked. Black tea not only does not hurt the stomach, but can nourish the stomach.

The contraindications of black tea:

1, stone patients and people suffering from tumors.

2, with anemia, insomnia with mental exhaustion.

3, usually easily agitated or more sensitive, poor sleep and weaker people.

4, people with stomach heat.

5, tongue tire thick people, bad breath, easy to acne people, eyes red people.

6, people who are taking medication.

People's Daily News - What are the effects and contraindications of black tea? These people should not drink black tea