It seems that everyone is becoming more and more rational. Wei Wei is very pleased. Everything can't be based on "legends", so today Weiwei systematically sorted out various investigations and studies on tea. Let's see where the tea is good!
Chachuan
Besides water, tea is one of the most popular drinks in the world. In China, the tradition of drinking tea has been passed down for centuries. The amount of green tea used by China people accounts for 20% of global tea consumption; Tea drinking is becoming more and more popular in western countries, and Britain has become one of the countries with the largest amount of tea drinking in the world. However, the consumption and popularity of different teas are regional. For example, people in China, Japan, the Middle East, South Africa and other Asian countries mainly drink green tea, while people in the United States, Britain and other western countries are used to drinking black tea.
Classification of tea:
In China, according to the different colors, shapes and aromas of tea leaves, there are many ways to classify tea leaves, among which the most common one is to classify tea leaves into six types according to the different fermentation degrees: green tea, black tea, green tea, black tea, yellow tea and white tea.
Green tea: It belongs to non-fermented tea and is the most abundant tea in China. Common green teas include West Lake Longjing, Dongting Lake Biluochun and Huangshan Mao Feng.
Black tea: mainly formed by fermentation. The so-called fermentation is actually colorless polyphenols in tea. Under the catalysis of polyphenol enzyme, it is oxidized to form a red oxidized polymer-black tea pigment. Therefore, compared with green tea, the content of tea polyphenols in black tea is greatly reduced, and its detectable health care function is also greatly reduced. Common black teas are Qi Hong, Jin Junmei and Chuan Hong.
Green tea: also known as oolong tea, it belongs to semi-fermented tea, which is a kind of tea between green tea and black tea, and its appearance is bluish black. Oolong tea can be divided into northern Fujian oolong, southern Fujian oolong, Guangdong oolong and Taiwan Province oolong.
Black tea: the raw materials are generally coarse and old, and the production process often takes a long time to accumulate and ferment, so the tea leaves are dark brown. Due to the difference of origin and technology, it is divided into Yunnan Pu 'er tea, Sichuan Border tea and Guangxi Liubao tea.
Yellow tea: represented by Mengding yellow bud, Huangshan yellow bud and Junshan silver leaf.
White tea: It belongs to micro-fermented tea, which is mostly found in Bai Hao needles and Bai Mudan.
In Europe, tea is divided into three categories according to product characteristics: black tea, oolong tea and green tea. Japan is divided into non-fermented tea, semi-fermented tea, fully fermented tea and post-fermented tea according to the degree of tea fermentation.
The relationship between tea and health
Unfermented tea is rich in polyphenols, including catechins and tea polyphenols. Animal experiments show that these two substances have anticancer, antimutagenic and antioxidant activities. What are the convenient and preventive health care functions? Let's look at it together: (Therefore, the higher the fermentation degree of tea such as black tea and black tea, the lower the polyphenol content, and the various health care functions introduced below mainly refer to green tea)
Type 2 diabetes: Studies show that drinking 16 grams of tea every day can reduce the risk of type 2 diabetes; Drinking tea can reduce fasting blood glucose and glycosylated hemoglobin concentration in patients with type 2 diabetes; The active ingredients in tea can protect islet cells and protect type 2 diabetes.
Stroke: Drinking 12g of tea every day can reduce the risk of stroke. Catechins in tea have antioxidant, anti-inflammatory, anti-malignant cell proliferation and improved plasma antioxidant capacity, which can protect stroke through various mechanisms.
Cardiovascular disease: Drinking tea can reduce the risk of cardiovascular disease. Studies have found that black tea can reduce low density lipoprotein and blood pressure in patients with cardiovascular diseases; Green tea (daily 12g) can significantly reduce total cholesterol, low density lipoprotein and blood pressure in patients with cardiovascular diseases. Low density lipoprotein can lead to atherosclerosis, and tea polyphenols can be used in all aspects of atherosclerosis to delay its occurrence and development.
Obesity: drinking tea has a positive effect on losing weight and maintaining weight, and drinking tea often can lose weight!
Gastric cancer: Studies have shown that drinking green tea in China and Japan can reduce the prevalence of gastric cancer; Black tea also seems to have the effect of preventing gastric cancer.
Breast cancer: Drinking 12g green tea every day may reduce the risk of breast cancer.
In addition, drinking tea, especially green tea, has been proved to reduce the risk of rectal cancer, ovarian cancer, esophageal cancer, lung cancer, Parkinson's disease, kidney disease and hip fracture.
Drinking tea has so many benefits, especially green tea, which can prevent many chronic diseases, malignant diseases and obesity. No matter what the principle of these actions is, our scientists have confirmed it in their research, so we only need to drink: 1~2 cups of tea every day, which is equivalent to about 12~ 16 grams, and form the habit of drinking tea and keep it.