喝茶养生是真的！东方绿茶 VS 西方红茶，谁更抗衰？

寒风渐起，坐在暖暖冬阳下，捧着一杯茶，看着袅袅上升的雾气啜上一小口，多是一件美事啊！只是，有的人捧的是绿茶，有的人捧的是红茶，更多的人捧的则是焦糖奶茶半糖加珍珠加布丁加芋圆……（巧了，派派手里捧的正是这个）

茶是大家公认的“健康饮品”，但是喝茶究竟有哪些好处？又是哪种茶最好？这场“茶艺竞技赛”里，从最常见的绿茶到最人气的奶茶都在跃跃欲试，下面就请看，年度茶艺大赏，pick你心中的茶类“南波万”！

据记载，早在公元前2737年左右，茶已经首次被我国人作为饮料或药物消费[1]，而经过五千年的发展至今，茶早已冲出国界走向国际，得到了全世界人的喜爱。现如今，全世界每年生产和消费约30亿公斤茶，均摊到每个人每天的消耗量高达120ml[2]。

在这个漫长的发展过程中，茶早已不是简单的“东方树叶”，茶的概念也变得多样起来。茶叶、抹茶、花茶、草药茶、甚至是奶茶，都可以属于“茶”的范畴。

看遍纷繁复杂的茶种类，研究最多、相关报道最详实的还是最传统的茶叶。降低心脑血管疾病及神经退行性疾病的风险、降低肥胖和糖尿病风险、改善免疫等[3]，茶叶促进人类健康的表现不可胜举，就让我们从生物学的角度稍加阐释。

No.1

降低死亡率

早在2007年，绿茶提取物就凭借它在促进健康领域的长久良好名声，进入了美国国家官方抗衰物质“造星计划”ITP，甚至比二甲双胍、阿卡波糖等老牌抗衰药更早。虽然在延长寿命上的效果并不明显，但是绿茶提取物的确能降低中年雌性小鼠的死亡率[4]。

图注：绿茶提取物能降低中年雌性小鼠的死亡率，但不能延长其寿命

No.2

抗光老化

光老化是由紫外线造成的皮肤及机体的损伤和衰老，DNA损伤、细胞衰老都是光老化可能带来的危害。

而茶具有良好的清除氧自由基的能力，这使其成为抗光老化疗法的潜在候选者。具体表现为：能增加胶原和弹性蛋白纤维的水平[5]、缓解紫外线带来的细胞损伤[6]、以及通过对衰老相关途径daf-16的调节[7]延长健康寿命。

在紫外线的威胁下，绿茶提取物不仅能减少皮肤色素沉着和皱纹的产生[8]，还能延长线虫等模式生物的寿命[9]。

图注：绿茶抗光老化的途径和方法

No.3

抗逆特性

除了抗光老化，茶还能增加人类等多种生物抵抗内源和外源压力的能力，防止各种疾病和损伤物的侵扰。

例如，茶能通过抗氧化、抗高血压、抗炎、抗增殖、抗血栓形成和降脂活性的血管保护作用[10]；茶能下调卵黄原蛋白家族基因的表达来减少秀丽隐杆线虫中的脂滴和脂肪堆积[11]；茶能降低哺乳动物模型体内镉和铅等有毒金属的活性[12]；茶还能降低人类患癌症的风险[13]；此外，茶还能通过减少自由基形成来保护人成骨细胞免于吸烟带来的损伤[14]。

No.4

神经保护特性

一些研究显示，饮用茶可降低阿尔茨海默病、帕金森病和认知障碍的患病率[15]。

茶不仅能直接清除氧自由基减少氧化损伤对神经系统的影响[16]，还能调节亨廷顿蛋白、β淀粉样蛋白和α-突触核蛋白等有害蛋白质在大脑中的积累[17]，清除阿兹海默症等神经退行疾病的发病主要诱因。

No.5

增加自噬

生物体中，细胞能通过自噬维持细胞稳态，并促进细胞在代谢应激下的存活[18]。而茶也能通过诱导和延长自噬增加细胞活力，延缓细胞死亡，继而保护机体健康，降低糖尿病性心肌病和癌症等疾病的风险[19]。

通过对茶对人体健康益处的调查派派发现，各种不同的茶也在对健康的作用上差距甚微，如果一定要分个高下，那么在一些文献中也能找到些许端倪：

在一项对地中海群岛人群的调查中发现，和喝红茶的人群相比，喝绿茶的人群表现出更高水平的身体活动、更低水平的高血压风险和更高的健康衰老指数[20]，绿茶在抗蛋白质变性的抗炎作用等方面可能也比红茶更优秀[21]；而红茶红茶在预防辐射引起的主动脉血管紧张素活性增加和氧化应激方面比绿茶更有效[22]；

不同的茶产生不同的抗衰养生效果有所差异，归根结底还还是因为各种茶叶中的有效生物活性物质可能有所差异。

茶叶里的主要生物成分由多酚（~90%）、氨基酸（~7%）、茶氨酸（3-没食子酰奎宁酸和5-N-乙基谷氨酰胺等）、原花青素和咖啡因（~3%）组成。茶叶多酚是提供茶叶健康益处的“主力军”，其主要成分包括儿茶素和黄酮醇。

儿茶素里包括儿茶素（C）、表儿茶素（EC）、没食子儿茶素（GC）、表没食子儿茶素（EGC）、表儿茶素没食子酸酯（ECG）、表没食子儿茶素没食子酸酯（EGCG）和没食子儿茶素没食子酸酯（GCG）等，其中EGCG、ECG和EGC占儿茶素总量的80%[23]。

而茶叶里的黄酮素包括杨梅素、山千香素、槲皮素、绿原酸、香豆奎宁酸和可可绿素等，物质太多，不一而足，但是每种的作用效果都不相同，各有千秋。

儿茶素

儿茶素具有抗氧化能力，其对氧自由基的清除能力比维生素C，维生素E或β-胡萝卜素更强大[24]；同时，儿茶素还有一定的癌症预防功效，能延缓皮肤肿瘤等的发作[25]；儿茶素还容易和其他物质相结合形成复合物，如咖啡因、蛋白质和铁等因此也能减少这些物质的吸收[26]。

茶黄素

茶黄素是由儿茶素氧化生成，但是也具有一定的抗氧化能力，能抑制体内脂质过氧化，并发挥保护淋巴细胞的作用[27-28]。

咖啡因

咖啡因能增强认知功能、改善神经肌肉协调、情绪提升和缓解焦虑有关[29]，虽然这种物质以“咖啡”冠名，但有意思的是，茶叶中的咖啡因含量（最高可达5%）高于咖啡豆（1.5%）[30]。

茶氨酸

茶氨酸主要为茶叶提供独特甜味和鲜味[31]，同时，茶氨酸还与放松和提高学习能力有关[32]，并能抑制肿瘤[33]，调节血压[34]，促进减肥[35]和改善免疫系统[36]。

黑茶、白茶、乌龙茶、红茶和绿茶其实来自相同的物种—茶树，其差异就在于收获时间和加工方式不同，尤其是氧化水平不同。黑茶是完全经过氧化的，乌龙茶则是部分氧化，而绿茶和白茶则并未被氧化[37]。

作为同一物种不同加工工艺的产物，几种茶树茶叶的生物活性物质种类其实没有区别，但是各种物质的含量却存在细微差异：

① 因为发酵程度的不同，发酵程度最低的绿茶、白茶的儿茶素水平最高，而发酵程度最高的黑茶、红茶和乌龙茶儿茶素水平较低，而茶黄素恰好相反，绿茶中最少，红茶和乌龙茶中较高；同时，在发酵的过程中，茶叶里的咖啡因水平不断上升，因此，红茶里的咖啡因的水平相较绿茶更高[38]。

② 生产季节、阳光照射、施肥情况和采摘部位也都会影响茶叶中各类物质的含量，夏叶儿茶素含量高于春叶；施钾肥的茶叶中儿茶素和茶氨酸更高[39]；阳光照射越多，儿茶素越多、茶氨酸越少；相比粗叶茶，嫩叶茶中茶氨酸、可可碱、咖啡因和儿茶素含量更多[40]。

虽然说红茶、黑茶等中的儿茶素水平不及绿茶、白茶等，但是这些发酵程度高的茶叶中，茶黄素的水平较高，可以填补因为儿茶素不足产生的缺陷。

因为各种物质都有不一样的生物活性，因此很难说究竟是华人爱喝的绿茶更好，还是西方人爱喝的红茶更好，风味不同，只要适量饮用，都对健康有所裨益。

讲了这么多茶的好处，但是茶并非百利而无一害的饮品，在享受茶饮的同时，我们还需要注意以下几点：

No.1

用茶服药减药效

茶及其提取物能和心血管疾病药物辛伐他汀，纳多洛尔和华法林等相互作用，在某些情况下可能导致药物疗效降低或药物毒性风险[41]；茶还会影响抗生素阿莫西林摄入后的血浆浓度，从而降低抗菌药效[42]。

No.2

以茶代水或贫血

茶能影响到血红素铁的吸收[43]，同时，茶里的儿茶酚也能和铁相结合[44]。虽然一般饮用量下，这种抑制情况很难造成贫血等缺铁性风险，但是如果每天将茶当水喝，还是会造成一定的影响。所以饮茶虽好，可不要贪杯哦~

No.3

空腹饮茶伤肠胃

当空腹饮茶时，会产生一定的肝毒性和胃肠道疾病风险副作用，对孕期、哺乳期和易感人群来说尤其明显。因此，饮茶前最好不要空腹[45]。

No.4

奶茶≈茶？才不一样

包括派派在内的好多年轻人看完全文可能欣慰地抱抱自己：“不愧是我，每天都在坚持喝（奶）茶！”，那么，加了牛奶后，“喝茶”还一样吗？

实际恐怕不然。早在2014年，就有研究显示，糖和蜂蜜以浓度依赖性方式显著降低茶的抗氧化活性，加的越多，茶的健康度越低[46]。

想要通过喝奶茶健康延寿的小伙伴们可能要失望了，想要拥有茶的健康益处，首先还得学会拥抱茶的苦涩。

看完上面这么多有关茶的知识和信息，是不是从完全不同的角度对“茶道”有了更多的理解呢？不要再为茶叶的种类而争吵啦，只要是通过安全、正规生产流程的茶叶，不管绿茶红茶，能抗衰延寿，都是好茶！

—— TIMEPIE ——

这里是只做最硬核续命学研究的时光派，专注“长寿科技”科普。日以继夜翻阅文献撰稿只为给你带来最新、最全前沿抗衰资讯，欢迎评论区留下你的观点和疑惑；日更动力源自你的关注与分享，抗衰路上与你并肩同行！

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