新冠肺炎也怕茶____茶与健康国际研究成果

陸金平James Lu

碧螺春新茶碧绿的芽尖，迎着早春第一缕阳气劈开寒冬一切阴霾疫邪，宣告新的一年隆重开篇了。

手工制茶，杀青，搓揉，焙干一气呵成，这样制成的茶最大限度保留了茶原有的风味和极其宝贵的营养。

刚出锅的新茶，卷曲如螺，清香扑鼻。

80岁的老奶奶还采茶制茶，乐在其中，茶就是健康美好生活的一部分。

苏州的早春其实还在寒冬里，茶树几乎是最早发芽的植物，落叶植物还在冬眠，甚至野草都不见，唯有 茶........走在寒风里，送来芳香沁人心脾，正因如此，无害虫，所以碧螺春无农药之忧。

苏州西山丘陵地带的红土壤特别适合茶树栽培，太湖中的小气候环境和茂密的森林，果树形成了独特绿色环境，这里的茶甘甜温润，如饮山泉，回甘回味无穷。

茶叶我们喝了几千年，是仅次于水的人类喝的最多的饮料，在西方也越来越被人们认识接受，特别是现代人对健康生活方式的追求和要求，喝茶已经是一种时尚。茶也将越来越成为奢侈品。国际上对茶与人体健康的研究日新月异，研究成果可谓令人惊喜，对健康美颜作用巨大，下面我们一起来看看一些代表性的研究。

茶多酚抗病毒治流感研究

这是《分子学》杂志一篇关于茶叶抗病毒流感的文章，经对比研究发现绿茶可明显抑制病毒复制，对病毒包膜也有破坏作用，所以可以预防感冒，根据我几十年中医临床经验，我认定对新冠肺炎一定也有用，可惜还没有这方面的研究。 2018年四月在去往悉尼的飞机上，坐在我后面的一位男士一直咳嗽，当时我想完了，我一定会被传染，果然在飞机上时，我就怕冷，打喷嚏，流鼻涕，飞机到了直奔旅馆，非常幸运，旅馆居然有四种不同的茶包，其中一种是姜茶，我四种各拿一包放一起泡了杯浓浓的茶，就喝了这一次，感冒就没再加重，好了。

Effect of Tea Catechins on Influenza Infection and the Common Cold with a on Epidemiological/Clinical Studies

Daisuke Furushima, Kazuki Ide, and Hiroshi Yamada

Abstract

Influenza and the common cold are acute infectious diseases of the respiratory tract. Influenza is a severe disease that is highly infectious and can progress to life-threating diseases such as pneumonia or encephalitis when aggravated. Due to the fact that influenza infections and common colds spread easily via droplets and contact, public prevention measures, such as hand washing and facial masks, are recommended for influenza prophylaxis. Experimental studies have reported that tea catechins inhibited influenza viral adsorption and suppressed replication and neuraminidase activity. They were also effective against some cold viruses. In addition, tea catechins enhance immunity against viral infection. Although the antiviral activity of tea catechins has been demonstrated, the clinical evidence to support their utility remains inconclusive. Since the late 1990s, several epidemiological studies have suggested that the regular consumption of green tea decreases influenza infection rates and some cold symptoms, and that gargling with tea catechin may protect against the development of influenza infection. This review briefly summarizes the effect of tea catechins on influenza infection and the common cold with a on epidemiological/clinical studies, and clarifies the need for further studies to confirm their clinical efficacy.

Keywords: tea catechins, influenza infection, common cold, bioactivity, epidemiological study

1. Introduction

Influenza and the common cold are acute infectious diseases of the respiratory tract. Influenza, in particular, is a severe disease and presents a high morbidity and mortality burden on the population because it is highly infectious and can progress to life-threating diseases such as pneumonia or encephalitis when aggravated. The World Health Organization (WHO) reported annual infection rates of 5–10% among adults and 20–30% among children, and WHO also reported that more than 250,000 individuals die each year from a severe influenza-related illness such as pneumonia or encephalitis [1,2,3]. At least 14 pandemics occurred within the last 500 years before the global H1N1 pandemic in 2009 (H1N1pdm09) [4]. Influenza and the common cold spread easily via droplets and contact, and public prevention measures, such as hand washing and facial masks, are recommended for influenza prophylaxis. However, the beneficial effects of these non-pharmaceutical preventive measures are limited and not completely effective [5,6]. Therefore, new approaches for the prevention and treatment of influenza infections and the common cold are needed [7]. Recently, the preventative effect of catechin compounds contained in green tea against influenza infection and the common cold is attracting attention [8]. Catechins are a class of polyphenolic flavonoids that are included in tea leaves [9,10]. Tea leaves include (−)epigallocatechin gallate (EGCG), (−)epigallocatechin (EGC), (−)epicatechin gallate (ECG), (−)epicatechin (EC), and (+)catechin (C) [11]. Lin et al. [9] reported the following mean concentrations of total catechins among 13 types of Japanese and 15 types of Chinese green tea products: 17.80 mg/100 mg (13.74 for EGCG, 0.88 for EGC, 1.95 for ECG, 0.87 for EC) and 17.86 mg/100 mg (13.37 for EGCG, 0.44 for EGC, 2.91 for ECG, 0.55 for EC), respectively. The present review briefly summarizes the probable clinical inhibitory effects of tea catechins against influenza infection and common cold based on the results reported in clinical/epidemiological studies and highlights the benefits of catechin compounds.

2. Infection and Replication of the Influenza Virus

Influenza viruses are classified as type A, B, or C, of which types A and type B cause symptoms such as fever, muscle pain, chills, and cough [1]. They are also epidemiologically the most important for humans since they can recombine their genes with those of strains circulating animals, such as birds, swine, and horses. Conversely, the type C virus causes less severe symptoms and does not generally lead to influenza epidemics or pandemics. Type A and B viruses infect mucous membrane cells in the nose through two proteins, hemagglutinin (HA) and neuraminidase (NA), which are present as spikes on the surface of the virus particle [12]. According to a report by the Centers for Disease Control and Prevention (CDC) in the United States, 18 HA (from H1 to H18) and 11 NA (from N1 to N11) proteins are known, and the severe Spanish flu (1918) and Hong Kong flu (1968) pandemics were caused by the genesis of H1N1 and H3N2 subtypes, respectively. On the other hand, the type B virus is not classified into subtypes like the type A virus; instead, it is classified as a lineage and strain. Currently, two distinct type B virus lineages are circulating; B/Yamagata and B/Victoria [13].

The mechanism from influenza infection to onset is that, after the attachment of the influenza virus to host cells, the HA protein of the virus is recognized by N-acetylneuraminic acid in the host cell membrane. After the binding process, the virus enters the host cell and targets the perinuclear region via endosomal trafficking. Here, the endosomal membrane fuses with the virus resulting in its uncoating. The uncoated viral genome is then transported to the nucleus, where virus replication, assembly, and budding occur, and NA mediates the enzymatic cleavage of the viral receptor to release the progeny viruses [14,15].

3. Activity of Tea Catechins against the Influenza Virus

Catechins have been reported as potential anti-influenza virus agents in several experimental studies. An in vitro study showed that EGCG, the most abundant catechin in green tea, was shown to minimize the infectivity of the influenza A and B virus in Madin–Darby canine kidney cells [16,17]. Furthermore, EGCG and ECG inhibited the activity of viral RNA (ribonucleic acid), which suppressed virus propagation [18,19].

Catechins do not interfere with HA and NA functions; rather, they inhibit the interaction of a virus with the cell membrane when it invades a cell [20]. An animal experiment using chickens showed that a diet and water containing green tea components suppressed the replication of the influenza virus [21]. Furthermore, EGCG, ECG, and catechin-5-gallate have neuraminidase inhibitory activity, as demonstrated by a molecular docking study [22]. Also, the results of a molecular structural study showed that the interaction energy order, which is consistent with the effect of HA inhibition, was EGCG, ECG, EGC, and EC [23]. It has also been reported that EGCG exhibits broad-spectrum antiviral efficacy against various viral families, such as Flaviviridae, Retroviridae, Hepadnaviridae, Herpesviridae, Adenoviridae, Orthomyxoviridae, and Picornaviridae [16].

Several studies have reported that polyphenols enhance immune function [24,25,26]. An increase in natural killer (NK) cell activity and cytokine levels was observed in mice fed polyphenol-rich cereals [27]. Additionally, the administration of water-containing tea catechins maintained NK cell activity and prevented tumor metastasis in senescence-accelerated mice under an experimental setting [24]. Other studies regarding effectiveness of catechins against antivirals in fundamental studies are described in detail elsewhere [28,29]. Investigations of the antiviral effects of chemically-modified catechin derivatives have also been progressing in recent years [30,31].

4. Epidemiological/Clinical Studies on the Ability of Tea Catechins to Prevent Influenza Infection

The ability of catechins or natural tea compounds to prevent an influenza infection has been documented since the late 1990s [32,33,34]. Although experimental studies showed antiviral activity with tea consumption, evidence for its clinical efficacy is not conclusive. One epidemiological study ed on the association between green tea consumption habits and influenza infection, two studies assessed the effect of green tea based on dietary supplement consumption, and another five studies uated the effect of gargling with green tea on the prevention of influenza infection. The characteristics and findings of these studies are summarized in Table 1.

Table 1

Table 1

Characteristics of major studies on tea and its ingredients against influenza infection.

Park et al. [35] examined the effect of green tea consumption habits on preventing influenza infection by a cross-sectional study using a questionnaire. Their study was conducted in several primary schools in Shizuoka prefecture, Japan, and included 2050 children who returned the questionnaire. They revealed that there was an inverse association between 1–5 cups per day (1 cup = 200 mL) of green tea consumption and influenza infection (1–3 cups per day vs. <1 cup per day (reference), the adjusted odds ratio (OR) was 0.62 and the 95% confidence interval (95% CI) was 0.41–0.95; 3–5 cups per d vs. <1 cup per d, adjusted OR 0.54; 95% CI 0.30–0.94). In comparison, Rowe et al. [36] conducted a randomized controlled study using green tea capsules containing L-theanine and EGCG that equaled 10 cups of green tea per day and compared its consumption to that of a placebo. They enrolled 108 healthy adult participants that were randomly allocated to the green tea capsule group (N = 53) or the placebo group (N = 55), and they were followed for five months. The major outcome measure was presence of a cold or influenza symptoms. There were 32.1% fewer symptoms (p = 0.035) and 35.6% fewer symptom days (p < 0.002) in the green tea capsule group compared to the placebo group. Similarly, Matsumoto et al. [37] conducted a randomized controlled study using green tea capsules containing 378 mg per day of catechins that included 270 mg per day of EGCG and 210 mg per day of theanine and compared its

consumption to that of a placebo. They enrolled 197 participants that were randomly allocated to the green tea capsule group (N = 98) or the placebo group (N = 99), and they were followed for three months. They found that the incidence of clinically diagnosed influenza infection was significantly lower in the catechin group (4.1%) compared with the placebo group (13.1%) (adjusted OR 0.25; 95% CI 0.07–0.76). In addition, the time for which the patient was free from influenza infection was significantly different between the groups (adjusted hazard ratio 0.27; 95% CI 0.09–0.84).

5. Prevention of Influenza Infection and Common Cold by Gargling with Tea Catechins

There are several reports on prevention of influenza infection or common cold by gargling with tea catechins; however, both are epidemiological studies conducted in Japan. Gargling, which is washing one’s mouth and throat with a liquid kept in motion by breathing through it with a gurgling sound, does not seem to be a common practice in European and North American countries. However, in Eastern Asian countries, especially in Japan, gargling is a generally accepted traditional intervention used for preventing upper respiratory tract infections such as influenza and the common cold [8,38].

Two observational studies and three randomized controlled studies were conducted to determine the efficacy of gargling with green tea (Table 2). The observational study by Noda et al. [39] assessed the effectiveness of gargling to prevent febrile diseases and sickness absences among healthy children. In their study, 19,595 children aged 2–6 years were observed for 20 d, and they found that fever onset was significantly lower in those that gargled with green tea (adjusted OR 0.32 95% CI 0.17–0.61) compared to those that gargled with tap water (adjusted OR 0.70; 95% CI 0.58–0.85) (reference, non-gargling group). Also, the prospective cohort study by Yamada et al. [40] studied the effect of gargling with green tea in 124 residents living in a nursing home for the elderly. They consumed the tea catechins three times daily for three months at a concentration equivalent to about half that of a commercially available green tea beverage with 200 μg per mL of total catechins. They found that the incidence of influenza decreased compared to gargling with water (incident rate; 1.3% in the green tea group vs. 10.0% in the water group). In their study, an influenza infection was determined based on a rapid antigen detection test, which is commonly used in clinical practice.

Table 2

Table 2

Characteristics of major studies on gargling with tea and its ingredients for influenza infection.

Three randomized controlled studies that uated gargling with green tea have been reported. Yamada et al. [41] reported on the association between gargling with green tea and the incidence of influenza infection. They randomly allocated 404 participants aged 20–65 years living in an elderly nursing home into the catechin group (gargling with extracts containing approximately 400 μg per mL catechins including 59.3% EGCG) or the placebo group. After three months, the incidence of influenza infection was 1.0% in the catechin group and 2.0% in the placebo group. Although the infection rate was lower in the catechin group than in the placebo group, the difference was not statistically significant (p = 0.84). Similarly, Toyoizumi et al. [33] and Ide et al. conducted a randomized controlled study on school-age populations [38,34]. They used bottled green tea solids that contained 560 μg total catechins per mL including 18% EGCG (N = 307 participants) or 370 μg total catechins per mL including 18% EGCG (N = 747), respectively. After three months, the incidence of influenza infection in either study was not significantly different between the green tea gargling group and the control group based on univariate and the multivariate analyses (p = 0.96 and p = 0.24, respectively) Recently, Ide et al. [42] reported on a meta-analysis that included randomized controlled studies and prospective cohort studies to assess the effect of gargling with tea on the prevention of influenza infection [32,33,34,35,36,37,38,39,40,41]. A total of 1890 subjects were pooled and analyzed, and the integrated participants who gargling with tea had a lower risk of influenza infection than participants who gargling with a placebo or who do not gargle (fixed effects model: relative risk (RR) = 0.70; 95% CI 0.54–0.89; random effects model: RR = 0.71, 95% CI 0.56–0.91). However, it should be noted that a limited number of studies were included in the analysis and the potential publication bias could not be uated.

Although there are reports that suggest the prevention of influenza and common cold by gargling, it should be noted that the mechanism of preventing these respiratory infections with gargling is unclear. Generally, it is thought that many causative bacteria and viruses of respiratory infections invade from the nasal cavity and

文章很长，我就不翻译了，一起贴这里了，有兴趣的朋友可以看看，文章还研究了茶水漱口预防感冒，茶水组比对照组好，但不是特别明显，仍有争议，我看文章的注意力都放在茶多酚的作用上，其实还有其它成分的作用，如维生素C等。文章提到了茶叶可以提高人体免疫力，提高人体重要的K杀伤细胞数，对已知各种病毒感染均有抑制作用。这里要提出的是实验研究结果效果的好坏受茶叶质量和茶水浓度的影响很大，所以不同实验结果有差异。碧螺春茶中茶多酚含量是其它茶叶的五倍，这可能与其特殊地理环境和采摘方式有关，碧螺春茶集春夏秋冬一年生长营养于一芽，几乎只采初春发芽期的芽尖，及其快速杀青技术最大限度保留了茶叶的营养，保障了茶叶质量。

and infect the nasopharynx cells in several tens of minutes to hours. Therefore, it is hardly understood from the microbiological point of view as to how gargling, which is only carried out several times a day, acts prophylactically.

Although this has not been studied using green tea, regarding the acute upper respiratory tract infection effect of gargling with tap water, Satomura et al. reported that incidence rate had reduced to 36% in a cohort study involving adults [38]. Contrarily, a study conducted by Goodall et al. reported that gargling did not reduce the risk of upper respiratory tract infections in a randomized controlled study [43]. Therefore, a more detailed study is required to verify the effects of preventing influenza and common cold and whether this is the direct effect of gargle itself or the effect of catechin. In addition, to increase the clinical evidence or uate the beneficial effects, large-scale observational studies or randomized controlled studies are needed in the future.

6. Conclusions and Future Perspectives

Currently, research on the clinical effects of tea catechins on influenza and common cold is in the developing stage. As shown in Table 1, the results of two randomized control studies showed the clinical effects of tea catechins against influenza. Similar results were also reported in an observational study.

The results of three randomized control studies were not statistically significant; however, the result of a meta-analysis suggested that gargling with tea catechins confers lower risks of influenza infection.

In summary, although the number of clinical/epidemiological studies on tea catechins against influenza and common cold are limited, the present studies suggest the possibility of preventive effects on influenza and common cold.

A variety of experimental in vivo or in vitro studies on catechins and their chemical derivatives have been reported to have several anti-influenza virus effects, and three mechanisms have been proposed: (1) inhibition of attachment to the host cell, (2) replication inhibition, and (3) NA inhibition in the virus. In this review, the results of several clinical studies on green tea or its ingredients were briefly summarized. Although experimental studies indicated the antiviral activity of tea components, there is limited clinical evidence to support their utility for preventing influenza or the common cold. Because the reported clinical trials for the efficacy of catechins or other green tea ingredients were small-scale studies, it is difficult to deduce a clear conclusion. Additional large-scale observational studies or randomized controlled studies are needed to establish or confirm their clinical efficacy in humans in future studies.

In 2009, the world experienced a swine influenza virus pandemic. In addition, there are concerns about human infection with a highly pathogenic avian influenza virus that is prent locally. Furthermore, the prence of viruses that acquired resistance to existing NA inhibitors such as oseltamivir (Tamiflu) and zanamivir (Relenza) has also been confirmed. Under such circumstances, the development of new drugs that inhibit virus infection with different mechanisms of action are urgently needed. We hope that future studies and additional information will clarify the potential for catechins to serve as an effective antiviral therapy with the currently approved preion drugs.

Acknowledgments

We would like to thank the all members of the Department of Drug uation & Informatics, School of Pharmaceutical Sciences, University of Shizuoka for their in valuable support to this study.

这是篇研究茶叶对人体健康的综述文章，文章也很长，对茶叶各方面的作用研究进行了归类，涉及抗癌，对心血管糖尿病等方方面面，有篇类似的中文文章，内容几乎是翻译过来的，我就拿来主义，省的我翻译了，在此感谢了。

綠茶(兒茶素)的功效及副作用(第1種令人期待)

2017 年 8 月 11 日 By Oliver S（在此感谢😊）

綠茶是當今茶飲中消費量最大的種類，又稱不發酵茶，是茶葉摘取後經過殺青（一種加熱過程）、揉捻、乾燥等工藝所製成的茶葉，由於未經發酵，因此能保留了茶葉內的多種茶多酚及維生素

綠茶以茶湯碧綠，綠葉飄逸而聞名，而其中最具功效的就屬兒茶素（Catechin），也是茶湯中澀味的主要來源，飲用綠茶時不只是精神上的享受，更能保健防病

除了具有優異的抗氧化效果，還能清除體內過多的有害自由基，具有預防癌症、心血管疾病、降體脂肪及延年益壽等多種功效。

茶特别是好茶再也不是最便宜的饮料了，作者显然没来过中国。

Tea, next to water is the cheapest beverage humans consume. Drinking the beverage tea has been considered a health-promoting habit since ancient times. The modern medicinal research is providing a scientific basis for this belief. The evidence supporting the health benefits of tea drinking grows stronger with each new study that is published in the scientific literature. Tea plant Camellia sinensis has been cultivated for thousands of years and its leaves have been used for medicinal purposes. Tea is used as a popular beverage worldwide and its ingredients are now finding medicinal benefits. Encouraging data showing cancer-preventive effects of green tea from cell-culture, animal and human studies have emerged. Evidence is accumulating that black tea may have similar beneficial effects. Tea consumption has also been shown to be useful for prevention of many debilitating human diseases that include maintenance of cardiovascular and metabolic health. Various studies suggest that polyphenolic compounds present in green and black tea are associated with beneficial effects in prevention of cardiovascular diseases, particularly of atherosclerosis and coronary heart disease. In addition, anti-aging, antidiabetic and many other health beneficial effects associated with tea consumption are described. Evidence is accumulating that catechins and theaflavins, which are the main polyphenolic compounds of green and black tea, respectively, are responsible for most of the physiological effects of tea. This article describes the evidences from clinical and epidemiological studies in the prevention of chronic diseases like cancer and cardiovascular diseases and general health promotion associated with tea consumption.

METABOLISM AND BIOAVAILABILITY

For all catechins, the metabolic pathways of methylation, glucuronidation and sulfation have been observed. Methylation, a major metabolic pathway, forms the metabolites 3′ and 4′-O-methyl-(−)-EC and O-methyl-(−)-EC-glucuronide, 4″-O-methyl-ECG, 4′-O-methyl-EGC, 4″-O-methyl-EGCG and 4′,4″-di-O-methyl-EGCG, and 4″-O-methyl-EGCG-3′-O-glucuronide and 3′,4′- or 3′,5′-di-O-methyl-EGCG-4″-O-glucuronide [6]. In human liver cytosol, (−)-EC was efficiently sulfated mainly through SULT1A1 while in the intestine, both SULT1A1 and SULT1A3 also contributed to the sulfation. (−)-EC was not glucuronidated by human liver and small intestinal microsomes. It has also been reported that there was no confirmation of glucuronidation by human colon microsomes or by recombinant UDP-glucuronosyltransferase-1A7 (UGT1A7), which is present in stomach and esophagus, but not in liver. (−)-EC was efficiently glucuronidated with the formation of two glucuronides in rat liver microsomes. Sulfation of (−)-EC was a major pathway in human liver and intestine without glucuronidation [7]. The absorption of green tea catechins in the small intestine is quite small. Flavanols are absorbed without deconjugation or hydrolysis and pass through biological membranes. The greater part of ingested green tea catechins reaches the large intestine and encounters the colonic microflora, with further hydrolysis of glycosides into aglycones and extensive transformation into various aromatic acids like phenylvalerolactones and hydroxyphenylpropionic acids [8]. In humans, plasma bioavailability of green tea catechins is very low. After the administration of either 697 mg of green tea or 547 mg of black tea to healthy volunteers, plasma EGC and EC content was 0.26–0.75% compared with EGCG and ECG with 0.07–0.20% with similar observations in urine [9]. With a single catechin, plasma concentration was found to be 1.53 M at a dose of 1050 mg for (−)-EC, 3.1 μM at a dose of 664 mg for ECG, 5 μM at a dose of 459 mg for EGC and 6.35 μM at a dose of 1600 mg for EGCG [6]. Six metabolites were identified in human urine: (−)-EC-glucuronide, three (−)-EC-sulfates, two O-methyl-(−)-EC-sulfates. Microbial metabolites (−)-5-(3′,4′-dihydroxyphenyl)-γ-valerolactone, and their glucuronide conjugates were also present. The major pathway for the elimination of EGCG is the biliary excretion. The total amount of metabolites excreted in urine is associated with maximum plasma concentrations. Urinary recovery was 0.5–6% for some tea catechins [10]. The half-lives of flavanols are 2–3 h in plasma, except EGCG, which is eliminated more slowly probably due to higher biliary excretion and greater complexing with plasma proteins [11].

綠茶(兒茶素)的科學實證功效（好處）

有益於心血管疾病

心血管疾病可說是威脅人類生命的頭號殺手，造成成年人（15-69歲）早死的原因中，有63%與它有關，每年約奪走千萬條寶貴生命，尤其嚴冬季節更是好發期

心血管疾病主要風險因子有：血糖代謝異常、高血壓、高血脂、抽菸及老化

一則統合分析（meta-analysis，包含9則研究，參與者共259,267人）指出，有喝綠茶習慣者，有助於降低心血管疾病及相關缺血性疾病風險（ischemic related diseases，如中風、腦梗塞、心肌梗死、腦出血）。

背後機制與綠茶中豐富的植物類黃酮（兒茶素／Catechin）有關，具有抗氧化、抗發炎、維持血管內皮穩定性等效果。

TEA AND CARDIOVASCULAR DISEASES

Consumption of tea is increasingly being shown to be associated with enhanced cardiovascular and metabolic health. Green tea caused an increase in the activity of enzymes implicated in cellular protection against reactive oxygen species: superoxide dismutase in serum and the expression of catalase in the aorta. This action is combined with direct action on oxygen species by a decrease in the nitric oxide plasma concentration [45]. Green tea catechins affect lipid metabolism by different pathways and prevent the appearance of atherosclerotic plaque. Its intake decreases the absorption of triglycerides and cholesterol and these findings are in accordance with the fact that it increases excretion of fat [46]. In patients, who underwent coronary arteriography for the first time in China, green tea consumption was associated with a reduced risk of coronary artery disease in male patients, with an adjusted odds ratio of 0.62 compared with those who did not drink green tea. Compared to non-tea drinkers, the adjusted odds ratios were 1.09 in male patients consuming less than 125 g of dried green tea leaves per month, 0.36 for 125–249 g per month and 0.36 for more than or equal to 250 g per month. There were similar dose-response relationships for frequency, duration, concentration and starting age of green tea drinking in male patients, while no inverse association was found between green tea consumption and coronary artery disease in female patients [47]. In a matched case-control analysis including 518 myocardial infarction, 333 hemorrhagic stroke, and 1927 ischemic stroke cases, the associations of these lifestyle factors with myocardial infarction and stroke were uated. Alcohol consumption was inversely associated with myocardial infarction, tea consumption was inversely associated with hemorrhagic and ischemic stroke and weight increase from age 20 to 40 was positively associated with myocardial infarction and stroke in a dose-response manner [48]. In a case-control study in southern China, a significant decrease in ischemic stroke risk was observed for drinking at least one cup of tea weekly when compared with infrequent or non-drinkers, the risk reduction being largest by drinking one to 2 cups of green or oolong tea daily. Significant inverse dose-response relationships were also found for years of drinking and the amount of dried tea leaves brewed [49]. In a meta-analysis, data from 9 studies involving 4378 strokes among 194,965 individuals was pooled. Individuals consuming more than or equal to 3 cups of tea/day had a 21% lower risk of stroke than those consuming less than 1 cup/day regardless of their country of origin with the proportion of heterogeneity not explained by chance alone being 23.8% [50].

癌症預防

癌症是目前多數人害怕健康議題，甚至比老化、恐怖分子或是失智還要令人畏懼，但其實癌症也是疾病之一，只是它不容易被發現，一但產生異狀，通常已是中後期，導致生命飽受威脅

而多則統合分析指出，在部分情境下，有喝綠茶習慣能降低多種癌症的發生風險（包括肝癌、乳癌、肺癌、食道癌、大腸癌、前列腺癌及膽管癌等）。雖然確切機制未明，但可能與以下有關

•抑制NF-κB發炎因數，促進癌細胞凋亡：NF-κB又被稱為癌症的主程式，是癌細胞能不斷擴大與逃避免疫細胞追殺的關鍵。

•對抗癌腫瘤血管新生，防止轉移。

•活化Nrf2轉錄因數，增加排毒及抗氧化能力：Nrf2轉錄因數又被稱為抗氧化總司令，可活化多種解毒酵素與抗氧化蛋白，清除體內的多餘自由基及致癌物，可說是天然解毒劑。

另則前瞻性研究（prospective study，追蹤期11年，對象為164,681位男性）也觀察到，有關綠喝綠茶習慣者，全因死亡率、心血管疾病及罹癌風險都顯著低於未喝者。

CANCER PREVENTIVE EFFECTS OF TEA IN HUMANS

Earliest documented cancer preventive effect of tea is our study in 1988 [12]. Currently, there are 1000 scientific publications in the scientific literature found on PubMed documenting cancer preventive ability of tea. Several studies initiated in our laboratory and subsequently verified from many other laboratories have suggested that catechins and theaflavins found in tea may reduce the risk of various types of cancers in humans. Various reports have shown an inverse association of tea consumption with the development of certain types of cancer [2, 13, 14]. The reported effects of tea on skin, prostate, lung and breast cancer in humans are shown in Table 1.

Table 1

Table 1

Reported Effects of Tea on Skin, Prostate, Lung and Breast Cancer in Humans.

This review article describes the major epidemiological and clinical studies on tea consumption and the risk of cancer at different organ sites in humans. We also present the evidences for the association of tea drinking and its effects on diabetes, arthritis and neurological system in humans.

i. Tea and Skin Cancer

Various studies have reported beneficial effects of regular tea consumption against squamous cell carcinoma of the skin. In a population-based case-control study, adjusting for brewing time, the association between squamous cell carcinoma and hot black tea consumption suggests a significantly lower risk in consumers of hot tea compared to non-consumers. It was suggested that tea concentration, brewing time and beverage temperature have major influences on the potential protective effects of hot black tea in relation to squamous cell carcinoma of the skin [15].

ii. Tea and Prostate Cancer

Among many dietary agents investigated for chemopreventive properties against prostate cancer (PCa), green tea and its constituent polyphenols (GTP) have received much attention. A Phase II trial was conducted in patients with androgen independent prostate carcinoma to investigate the explored the antineoplastic effects of green tea. Forty two patients asymptomatic who had manifested, progressive prostate specific antigen (PSA) elevation with hormone therapy were uated. Six grams of green tea per day orally in 6 divided doses were given to patients and each dose contained 100 calories and 46 mg of caffeine. A decline in more than or equal to 50% in the baseline PSA value occurred in a single patient and it was not continued beyond 2 months. Median change in the PSA value increased by 43% at the end of the first month. Grade 1 or 2 green tea toxicity occurred in 69% of patients, along with Grade 3 toxicity and one episode of Grade 4 toxicity [19]. Green tea consumption habit of 49,920 men aged 40–69 years was investigated in the Japan Public Health Center-based prospective study. During that time, 404 men were newly diagnosed with PCa, of which 114 had advanced cases, 271 were localized, and 19 were of an undetermined stage. It was established that localized PCa was not affected by the consumption of green tea, there was a dose-dependent decrease in the risk of advanced PCa by intake of green tea [23]. It has been reported that there was a significant reduction in serum levels of PSA, hepatocyte growth factor and vascular endothelial growth factor in men with prostate cancer after brief treatment with green tea extract containing EGCG (Polyphenon E), with no elevation of liver enzymes [24]. In PCa patients scheduled to undergo radical prostatectomy, a randomized, double-blind, placebo-controlled trial of Polyphenon E was conducted to determine the bioavailability of GTP in prostate tissue and to measure its effects on systemic and tissue biomarkers of PCa. Polyphenon E or placebo daily was given to patients for 3 to 6 weeks before surgery. Treatment with Polyphenon E caused promising but not statistically significant changes in the levels of serum PSA, serum insulin-like growth factor (IGF) axis, and oxidative DNA damage in blood leukocytes. In the prostatectomy tissue, tissue biomarkers of cell proliferation, apoptosis, and angiogenesis did not differ between the treatments. Patients receiving Polyphenon E had a decrease in Gleason score between biopsy and surgical specimens but it was not statistically significant [25].

iii. Tea and Lung Cancer

Various studies have demonstrated the relationship between tea consumption and threat of lung cancer. Tea drinking was associated with reduced risk of lung cancer in male cigarette smokers in a case control study in Uruguay [26].

有益於第二型糖尿病

第二型糖尿病是目前成長速度最快的疾病，特別是在亞洲地區，這是由於基因關係，就算不發胖，亞洲人罹病率也普遍比歐美人種高。

在一則日本研究中發現，經常喝綠茶者，能降低42%的糖尿病罹患率。同時在其它研究也指出，喝綠茶的確有抑制肝臟合成葡萄糖。，降血糖及改善胰島素敏感度的功效。

茶可以提高糖尿病患者胰岛素水平，降低糖化血红蛋白。

TEA AND DIABETES

Various studies have shown that tea may affect glucose metabolism and insulin signaling, causing interest in the health effects of tea consumption on diabetes. In a large cohort of U.S. middle-aged and older women from the Women’s Health Study, women who consumed more than or equal to 4 cups/day of tea had a 30% lower risk of developing type 2 diabetes than did those who did not consume tea [51]. In a retrospective cohort study among Japanese adults, adults who consumed more than or equal to 6 cups/day of green tea lowered their risk of diabetes by 33%, while no association with diabetes risk was found for oolong or black teas. Consumption of more than or equal to 3 cups/day of coffee lowered the risk of diabetes by 42% and high caffeine intake was also associated with a 33% reduction in risk of diabetes. A lowered diabetes risk was also observed in women after green tea and caffeine consumption [52]. The effects of continuous ingestion of a catechin-rich beverage in patients with type 2 diabetes who were not receiving insulin therapy in a double-blind controlled study were investigated. The patients were given green tea containing either 582.8 mg of catechins or 96.3 mg of catechins/day for 12 weeks. Waist circumference decreased in the catechin group than in the control group at 12 weeks. There was increase in insulin and the decrease in hemoglobin A(1c) levels in the catechin group than in the control group in patients treated with insulinotropic agent [53]. The possible effects of different daily doses of black tea intake on certain oxidative stress, inflammatory and metabolic biomarkers in patients with type 2 diabetes mellitus. Patients were given 150, 300, 450 and 600 ml of black tea extract (BTE) during the weeks 1, 2, 3 and 4, respectively, while the control group received 150 ml BTE throughout the intervention period. It was found that serum total antioxidant capacity was enhanced similarly in both test and control groups, but a suppressing effect on serum malondialdehyde was observed with daily intake of 2 cups of BTE. After ingesting 4 cups (600 ml) of BTE a day, there was decrease in the level of serum C-reactive protein and increase in the glutathione levels. It was concluded that regular consumption of BTE had anti-oxidative and anti-inflammatory effects in patients with type 2 diabetes mellitus [54].

幫助減肥(特別是腹部脂肪)

減肥是個從未退燒的話題，尤其是對於坐辦公室的的上班族來說。坐太久不僅影響新陳代謝，還會造成腹部及臀部脂肪堆積，增加數倍罹患心血管疾病、糖尿病及癌症的風險。

而在多項隨機對照研究中發現，經常喝綠茶除了能加速新陳代謝，還有減重、降體脂肪、消除腹部脂肪的功效。

降低認知功能障礙風險

受少子化與醫療進步影響，多數先進國家面臨人口老化困惱，而老化帶來的功能退化，如認知障礙甚至是失智症便成為急需關切的議題

失智症的早期症狀眾多，其中一項便是認知障礙，有些人可能開始健忘，變得容易迷路，有的人可能焦慮不安，變得容易與人發生衝突

一則文獻統合分析（meta-analysis，包含17則研究，參與者48,435人）指出，攝取茶葉飲料有助於降低認知功能障礙風險。在進一步考量茶葉種類後發現，以綠茶的效果最顯著（降幅達36%），優於紅茶及烏龍茶。註１

劑量效應分析也發現，日常茶葉飲料飲用量每增加100 ml、300ml、500ml，認知障礙風險會分別降低6%，19%及29%

背後機制與綠茶中多酚類物質（兒茶素／Catechin）具有的抗氧化、抗澱粉樣蛋白生成有關

＊總結：經人口觀察研究確認，喝綠茶能降低認知退化風險，但仍待未來更多隨機臨床研究進一步驗證。

TEA AND NEUROLOGICAL EFFECTS

Due to lack of well-controlled clinical trials, the effect of tea in the progression of neurodegenerative disorders has not been studied on a large scale. The protective effect of EGCG against neuronal diseases may involve its radical scavenging and iron chelating activity and/or regulation of antioxidant protective enzymes. Reduced risk for Parkinson’s disease was observed for more than or equal to 2 cups/day of tea consumption and two or more cola drinks/day. The associations for tea and cola drinks were not affected by smoking or coffee consumption [57]. A case control study was conducted in China to examine the relationship between coffee and tea drinking, cigarette smoking, and other environmental factors and risk of Parkinson’s disease. It was found that one unit of coffee and tea (3 cups/day for 10 years) would lead to 22% and 28% risk reduction, respectively, of Parkinson’s disease demonstrating a dose-dependent protective effect of coffee and tea in an ethnic Chinese population [58]. The association of coffee and tea consumption with the risk of incident Parkinson’s disease among 29,335 Finnish subjects aged 25 to 74 years without a history of Parkinson’s disease at baseline was investigated. There were followed up for 12.9 years and during this time, 102 men and 98 women developed an incident Parkinson’s disease. It was noted that subjects who habitually drank ≥ 3 cups of tea/day had a reduced risk of incident Parkinson’s disease [59]. In the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women, all 157 incident Parkinson’s disease cases were identified. There was an inverse relationship of black tea with Parkinson’s disease risk that was not confounded by total caffeine intake or tobacco smoking, while green tea was unrelated to Parkinson’s disease risk [60].

降低肝指數(針對非酒精性脂肪性肝病患者)

肝臟是脂肪消化吸收分解的重要工廠，而脂肪肝指的是肝臟組織中約有5%–10%被脂肪所占滿，造成肝臟發炎、纖維化甚至是肝硬化的一種疾病，盛行率在成年人之中大約有40%。

而非酒精性脂肪性肝病（Non Alcoholic Fatty Liver Disease）指的是非飲用酒精所引起的脂肪肝，主要是由肥胖所引起，其次是藥物、糖尿病、高血脂等

在一則針對非酒精性脂肪肝患者的研究發現（樣本數為71人，肝指數ALT 、AST 均超越正常值），服用綠茶萃物，主成分為兒茶素（連續12週，每日500 mg）能顯著降低患者的ALT 、AST 肝損壞指數。

而作者也在結論後提到，降低肝指數的背後機制，與綠茶中兒茶素能降低肝細胞的氧化壓力與提升脂肪代謝有關（脂肪代謝異常造成氧化壓力上升是形成脂肪肝的原因之一）

茶可帮助减少得关节炎几率，增强骨密度。

TEA AND ARTHRITIS

Few studies have reported the beneficial effects of tea against arthritic disease in humans. In a study in Britain, it was found that those who drank tea had greater bone mineral density than those who did not drink tea [55]. Coffee, tea, and caffeine consumption were uated as risk factors for rheumatoid arthritis onset among older women in a prospective cohort study. Compared with those reporting no use, subjects drinking more than or equal to 4 cups/day of decaffeinated coffee were at increased risk of rheumatoid arthritis. In contrast, women consuming more than or equal to 3 cups/day of tea displayed a decreased risk of rheumatoid arthritis compared with women who never drank tea, while caffeinated coffee and daily caffeine intake were not associated with the development of rheumatoid arthritis. The associations of rheumatoid arthritis onset with the highest categories of decaffeinated coffee and tea consumption were stronger in women with seropositive disease compared with those with seronegative disease [56].

延長壽命，降低死亡率

醫學進步雖然讓人類壽命大幅增加，但各種慢性病卻讓生活品質降低，甚至臥病在床，因此如何無病到終老才是背後的重點

而上面曾提到，常喝綠茶能降低癌症、第二型糖尿病、心血管疾病的罹患率，因此能有效延長壽命，降低各年齡層的死亡率

在日本一則大型觀察發現（對象為40,530 位男女），每天喝5杯綠茶，確實能大幅減少各種原因帶來的死亡率（尤其是降低中風的風險最為顯著）。

碧螺春泡茶建议每次3克左右，太多太少均不合适，一天3--4次，茶叶也可吃下去，效果更好。 也可加几片姜和一两枚枣一起泡，对预防感冒流感效果更好。

为愛您和您愛的人订制最美的礼物吧🌹

有精美包装可供选择⭐️

碧螺春茶四斤新鲜的茶叶才能制作一斤干茶，有七万多个芽尖，需要四个人采一整天，采茶的工钱就超过千元了，所以喝碧螺春喝的是真正的功夫茶。

品茶季节也是踏青的季节，疫情终会随着春天的到来而消散，自然的神奇之处就在于走自然之道。