生活方式与饮食:证据到底支持什么
关于"吃什么、怎么动能保护心脏"的说法铺天盖地,其中有一部分有扎实的循证支持,也有很多只是流行的传说。这一课的目标不是给你一份"超级食物清单",而是帮你分清:哪些生活方式干预真正被指南推荐,效果有多大,以及它们的边界在哪里。
生活方式是基础,但不是万能
各大血脂指南都把健康的生活方式作为预防动脉粥样硬化性心血管疾病(Atherosclerotic cardiovascular disease,ASCVD动脉粥样硬化性心血管疾病 · Atherosclerotic cardiovascular diseaseASCVD/ˌæθəroʊskləˈrɒtɪk ˌkɑːrdioʊˈvæskjələr/由动脉粥样硬化引起的一类疾病的总称,包括冠心病、缺血性卒中、外周动脉疾病等。An umbrella term for diseases caused by atherosclerosis, including coronary heart disease, ischaemic stroke, and peripheral artery disease.)的基础措施,适用于几乎所有人——具体包括合理膳食、增加身体活动、控制体重、限制饮酒和戒烟 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。换句话说,生活方式改善是所有人的"第一步",而不是只有查出问题的人才需要。
但"基础"不等于"足够"。生活方式主要影响的是低密度脂蛋白胆固醇(Low-density lipoprotein cholesterol,LDL低密度脂蛋白 · Low-density lipoproteinLDL/ˌloʊ ˈdɛnsɪti ˌlaɪpoʊˈproʊtiːn/运输胆固醇进入外周组织的脂蛋白颗粒;其携带的胆固醇称 LDL-C,是动脉粥样硬化的核心致病因素,俗称“ 坏胆固醇”。The lipoprotein particle that carries cholesterol to peripheral tissues; its cholesterol cargo (LDL-C) is a central causal driver of atherosclerosis, popularly called 'bad cholesterol'.🧩 词根拆解 / word rootslow-density低密度 · low density+lipo-脂、脂肪 · fat希腊语 lipos 脂肪+protein蛋白质 · protein希腊语 prōtos 第一/首要,即 LDL-C)、甘油三酯(Triglyceride,TG甘油三酯 · TriglycerideTG/traɪˈɡlɪsəraɪd/由一分子甘油与三分子脂肪酸结合成的脂质,是人体主要的储能脂质,也是两大血脂之一;在血液中主要由乳糜微粒和 VLDL 运输。A lipid formed from one glycerol molecule bound to three fatty acids; the body's main energy-storage lipid and one of the two principal blood lipids, transported in blood mainly by chylomicrons and VLDL.🧩 词根拆解 / word rootstri-三 · three希腊语 treis 三+glyceride甘油酯(甘油与脂肪酸形成的酯) · an ester of glycerolglycerol 甘油 + -ide,TG)和高密度脂蛋白胆固醇(High-density lipoprotein,HDL高密度脂蛋白 · High-density lipoproteinHDL/ˌhaɪ ˈdɛnsɪti ˌlaɪpoʊˈproʊtiːn/参与胆固醇逆向转运的脂蛋白颗粒,俗称“好胆固醇”;但用药物单纯升高 HDL-C 并未被证明能降低心血管风险。The lipoprotein involved in reverse cholesterol transport, popularly called 'good cholesterol'; however, pharmacologically raising HDL-C alone has not been shown to reduce cardiovascular risk.🧩 词根拆解 / word rootshigh-density高密度 · high density+lipo-脂、脂肪 · fat希腊语 lipos 脂肪+protein蛋白质 · protein希腊语 prōtos 第一/首要,HDL-C)等可变指标;对于遗传因素占主导的指标(本课末尾会讲到的 Lp(a)),它几乎无能为力。理解这条边界,能帮你既不轻视饮食运动,也不对它抱有不切实际的幻想。
脂肪的"种类",比"油多油少"更关键
很多人以为控制血脂就是"少吃油"。更准确的说法是:脂肪的种类比总量更值得关注。
- 饱和脂肪(Saturated fat,SFA饱和脂肪 · Saturated fat (saturated fatty acids)SFA/ˈsætʃəreɪtɪd fæt/脂肪酸碳链上不含碳碳双键的脂肪,常温下多为固态,主要来自动物油脂、肥肉、黄油和棕榈油等;指南建议用不饱和脂肪替代它以降低 LDL-C。Fat whose fatty-acid chains contain no carbon–carbon double bonds, usually solid at room temperature, found mainly in animal fats, fatty meat, butter and palm oil; guidelines advise replacing it with unsaturated fat to lower LDL-C.🧩 词根拆解 / word rootssatur-饱和(碳链上的键已被氢“填满”) · filled/saturated (bonds fully taken up by hydrogen)拉丁语 saturare 使充满+-ated…化的(形容词/过去分词后缀) · adjective/participle suffix+fat脂肪 · fat,SFA)主要来自动物油脂、肥肉、黄油、棕榈油等。指南建议用不饱和脂肪替代饱和脂肪,以此降低 LDL-C 并改善整体脂蛋白谱 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934 [2]Tier 1Mach, Francois et al. 2019 ESC/EAS guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. European Heart Journal 2020doi:10.1093/eurheartj/ehz455。
- 反式脂肪(Trans fat,TFA反式脂肪 · Trans fat (trans fatty acids)TFA/trænz fæt/含反式(trans)构型双键的不饱和脂肪,多由植物油部分氢化产生,常见于某些人造奶油、酥皮点心和油炸食品;指南建议尽量完全避免。Unsaturated fat containing double bonds in the trans configuration, largely produced by partial hydrogenation of vegetable oils and found in some margarines, pastries and fried foods; guidelines advise avoiding it as far as possible.🧩 词根拆解 / word rootstrans-跨越、在对侧(指双键两侧碳链呈反式排列) · across/on the opposite side (the trans double-bond geometry)拉丁语 trans 越过+fat脂肪 · fat,TFA)主要来自部分氢化植物油(常见于一些人造奶油、酥皮点心、油炸食品)。指南给出的是最高级别的否定建议:应尽量完全避免 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。
- 不饱和脂肪(Unsaturated fat,Unsaturated fat (unsaturated fatty acids)不饱和脂肪 · Unsaturated fat (unsaturated fatty acids)/ʌnˈsætʃəreɪtɪd fæt/脂肪酸碳链上含一个或多个碳碳双键的脂肪,常温下多为液态,主要来自植物油、坚果和深海鱼等;指南建议用它替代饱和脂肪以改善脂蛋白谱。Fat whose fatty-acid chains contain one or more carbon–carbon double bonds, usually liquid at room temperature, found mainly in vegetable oils, nuts and oily fish; guidelines advise using it to replace saturated fat to improve the lipoprotein profile.🧩 词根拆解 / word rootsun-非、不 · not英语 un- 否定前缀+satur-饱和(碳链上的键被氢填满) · filled/saturated拉丁语 saturare 使充满+-ated…化的(后缀) · adjective/participle suffix+fat脂肪 · fat)来自植物油、坚果、深海鱼等,是用来"顶替"饱和脂 肪的更好选择 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。
所以指南的核心信息不是"戒掉所有脂肪",而是用植物来源的不饱和脂肪,替换动物来源的饱和脂肪与工业反式脂肪 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934 [2]Tier 1Mach, Francois et al. 2019 ESC/EAS guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. European Heart Journal 2020doi:10.1093/eurheartj/ehz455。这里的胆固醇(Cholesterol,Cholesterol胆固醇 · Cholesterol/kəˈlɛstərɒl/一种脂质分子,是细胞膜、类固醇激素和胆汁酸的必需成分;因不溶于水,需由脂蛋白在血液中运输。A lipid molecule essential for cell membranes, steroid hormones, and bile acids; being water-insoluble, it must be transported in the blood by lipoproteins.🧩 词根拆解 / word rootschole-胆汁(最早从胆结石中分离) · bile希腊语 kholē 胆汁+stere(o)-固体、坚硬 · solid/stiff希腊语 stereos 固体+-ol醇(化学后缀,表示这是一种醇) · an alcohol (chemistry))指标改善,主要就是通过这种"替换"实现的。
膳食胆固醇:值得限制,但不是唯一重点
膳食胆固醇(Dietary cholesterol,Dietary cholesterol膳食胆固醇 · Dietary cholesterol/ˈdaɪətɛri kəˈlɛstərɒl/随食物(尤其是蛋黄、肉类、奶酪等动物性食物)摄入的胆固醇,是血中胆固醇的外源来源,区别于人体自身(主要在肝脏)合成的内源胆固醇。Cholesterol taken in from food—especially animal-source foods such as egg yolks, meat, and cheese—the exogenous source of blood cholesterol, as distinct from cholesterol the body synthesises itself (mainly in the liver).🧩 词根拆解 / word rootsdiet-饮食、膳食 · diet希腊语 diaita 生活方式/饮食+-ary…的(形容词后缀) · adjective suffix)指随食物(尤其是蛋黄、动物内脏等)摄入的胆固醇。对于 ASCVD 高危人群以及高胆固醇血症患者,指南建议把每日膳食胆固醇摄入控制在 300 mg 以下 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。
需要提醒的是,指南把"限制饱和脂肪 与反式脂肪"和"控制膳食胆固醇"都列入饮食建议,并没有把某一种食物妖魔化成"头号元凶" [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。与其纠结于单一食物,不如关注整体的膳食结构。
多吃什么:纤维、全谷、蔬果与鱼
饮食干预不只是"减法",也有"加法"。
膳食纤维(Dietary fiber,Dietary fiber (fibre)膳食纤维 · Dietary fiber (fibre)/ˈdaɪətɛri ˈfaɪbər/食物中不能被人体消化酶分解的植物性成分,主要来自蔬菜、水果、全谷物和豆类;增加摄入有助于降低 LDL-C。The plant components of food that human digestive enzymes cannot break down, found mainly in vegetables, fruit, whole grains and legumes; increasing intake helps lower LDL-C.🧩 词根拆解 / word rootsdiet-饮食、膳食 · diet希腊语 diaita 生活方式/饮食+-ary…的(形容词后缀) · adjective suffix+fiber纤维 · fibre拉丁语 fibra 纤维)有助于降低 LDL-C [2]Tier 1Mach, Francois et al. 2019 ESC/EAS guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. European Heart Journal 2020doi:10.1093/eurheartj/ehz455。指南同时推荐增加蔬菜、水果、全谷物、薯类、膳食纤维和鱼类的摄入,作为预防 ASCVD 的膳食策略 [1]Tier 1Joint Committee for the Development of Chinese Guidelines for the Management of Blood Lipids et al. 2023 Chinese guideline for lipid management (English full text). Frontiers in Pharmacology 2023doi:10.3389/fphar.2023.1190934。这些食物之所以被反复提及,是因为它们既能提供纤维、又能替代高饱和脂肪的食物,是一种"