Black Tea is a fully Fermented tea. Traditionally, it was the only type of tea known in the West. Westerners tend to prefer black tea. Major production areas of black tea include China, Sri Lanka, India, Kenya, and others. Black tea goes through the processes of picking, withering, rolling, fermentation, and drying – an additional step of fermentation compared to Green Tea. Fermentation refers to the oxidation of the tea leaves in the air. This process reduces the levels of catechins and tannins in the tea leaves, producing new components such as theaflavins and thearubigins, as well as aromatic substances like alcohols, aldehydes, ketones, and esters. Therefore, black tea leaves appear black, or a mix of black and the Orange-yellow of young buds; the tea liquor is deep red in color; it has a pleasant aroma; and due to the reduced bitterness and astringency, the taste is sweeter and more mellow.
The Benefits and Effects of Black Tea
1. Diuretic Effect of Black Tea
In black tea, caffeine and aromatic compounds work together to increase blood flow to the kidneys, enhance glomerular filtration rate, dilate renal microvessels, and inhibit water reabsorption by the renal tubules, thus promoting increased urine output. This helps in excreting substances like lactic acid, uric acid (related to gout), excess salts (related to Hypertension), harmful substances, and alleviates edema caused by heart disease or nephritis.
2. Anti-inflammatory and Bacterial-killing Effect
Polyphenols in black tea have anti-inflammatory effects. Experiments have shown that catechins can bind to single-celled bacteria, causing the proteins to coagulate and precipitate, thereby inhibiting and eliminating pathogenic bacteria. Therefore, black tea is beneficial for patients with bacterial dysentery and food poisoning, and it is also commonly used in folk remedies to treat wounds, bedsores, and athlete's foot with concentrated tea.
3. Detoxification Effect
Experiments have proven that theaflavins in black tea can adsorb heavy metals and alkaloids, and decompose them. For modern people whose drinking water and food may be contaminated by industrial pollutants, this is indeed a blessing.
4. Stimulating and Fatigue-relieving Effect
Medical experiments have found that the caffeine in black tea stimulates the cerebral cortex, exciting the central nervous system, enhancing alertness, focus, and mental agility, and improving memory. It also stimulates the cardiovascular system and heart, enhancing cardiac output and accelerating blood circulation, which benefits metabolism. Simultaneously, it promotes perspiration and diuresis, aiding in the rapid elimination of lactic acid (the substance responsible for muscle fatigue) and other waste products from the body, effectively relieving fatigue.
5. Moisturizing and Heat-clearing Effect
Drinking black tea in summer can quench thirst and cool the body because the polyphenols, sugars, amino acids, pectin, and other components in the tea react chemically with saliva, stimulating saliva secretion, making the mouth feel moist and producing a sense of coolness. Caffeine controls the hypothalamic temperature center, regulating body temperature. It also stimulates the kidneys to promote heat and waste excretion, maintaining physiological balance within the body.
In addition, black tea also has the effects of preventing tooth decay, aiding digestion, delaying aging, lowering blood sugar, blood pressure, and lipids, as well as anticancer and antiradiation properties. Black tea is also an excellent sports drink; besides quenching thirst and replenishing fluids, if consumed before engaging in activities requiring physical strength and endurance (such as marathon running), the caffeine in the tea provides a stimulating effect, enabling the body to first burn fat for energy while preserving glycogen stores, thus increasing endurance.
Suitable Groups for Drinking Black Tea
Black tea is a fully fermented tea, and its strong flavor is both its characteristic and benefit. It is particularly suitable for consumption during autumn and winter. During the fermentation and roasting of black tea, tea polyphenols undergo enzymatic oxidation reactions under the action of oxidase, reducing their content and decreasing the stimulation to the stomach. It is appropriate to drink black tea on an empty stomach. Additionally, the oxidation products of tea polyphenols can help with digestion, so black tea not only does not harm the stomach but can also nourish it.
Suitable groups: Hypertension, hyperlipidemia, coronary heart disease, arteriosclerosis, diabetes, excessive consumption of greasy foods, alcohol intoxication.
Unsuitable groups: Fever, poor kidney function, habitual constipation, peptic ulcers, neurasthenia, insomnia, pregnant women, breastfeeding mothers, children.