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体检报告上一般有两个胆固醇数据，一个是低密度脂蛋白胆固醇（LDL），它应该保持在130毫克/分升以下，越低越好；另一个是高密度脂蛋白（HDL），应该保持在40毫克/分升以上，越高越好。这是因为低密度脂蛋白是“坏”胆固醇，是导致动脉堵塞斑块、心脏病、中风和其他讨厌的东西的胆固醇，我们希望它的量尽可能少，另一方面，HDL是“好”胆固醇，我们希望它尽可能多。HDL之所以有个好名声，是因为它能与低密度脂蛋白结合，把它们带到肝脏，从而排出体外。但俗话说“物极必反”，这似乎也是好胆固醇的真实写照：过多的HDL实际上增加了动脉和心脏疾病的风险。一旦男性的HDL超过80毫克/分升、女性超过100毫克/分升，就处于危险区了，这一结论来自一项最近的研究。美国埃默里大学（Emory University）医学院心脏病科的医学教授阿尔沙德·盖伊姆（Arshed Quyyumi）表示：“直到最近，医学生接受的教育都是：HDL水平越高，健康风险越低。所以传统上，医生们一直把非常高的HDL水平作为真正健康的胆固醇状况标志。”盖伊姆是几项最新研究的论文作者，他对英国超过40万人进行了调查，这些人没有其他易患心脏病的风险因素。对于其中的男性来说，如果HDL水平低于40毫克/分升或超过80毫克/分升，他们的心脏和其他疾病风险就会上升；对于女性，一旦HDL水平超过100毫克/分升，风险就会攀升。这里的“攀升”，具体是多大的程度呢？是几个小的百分点，还是更大的增长？
The Bad Side of "Good" Cholesterol Josh Fischman: You go to the doctor for an annual checkup, right, Tanya?Tanya Lewis: Sure. As any good health editor would!Fischman: Me too. You get asked a bunch of personal questions, a cold stethoscope on your skin, and the doctor draws some blood for standard lab tests. Among those tests, when you get them back, are two cholesterol numbers.Lewis: Right. One is your level of low-density lipoprotein cholesterol, or LDL. It’s supposed to stay under 130 milligrams per deciliter—the lower the better.The other one is high-density lipoprotein, or HDL. And that’s supposed to stay above 40 milligrams per deciliter. The higher it is, the better, we’re told.Fischman: That’s because LDL is the “bad” cholesterol, the one that leads to artery-clogging plaques, heart disease, strokes, and other nasty stuff. We want less of it.HDL, on the other hand, is “good” cholesterol. We want more of it.Lewis: HDL has this good reputation because it binds to LDL, carrying that bad stuff to the liver. From there it gets flushed out of your body, where it can’t hurt you.Fischman: But … you know that old saying about having too much of a good thing? It seems to be true of good cholesterol.Lewis: So, is it possible to have too much HDL?Fischman: It is totally possible. Turns out that too much HDL actually raises the chances of artery and heart disease, the very things we’re trying to avoid.Once you get above 80 for men and 100 for women—and I’m going to stop saying milligrams per deciliter because it’s a mouthful—you’re in the danger zone. A bunch of recent studies have found this effect.But generally, that’s not what doctors have told patients.Quyyumi: The teaching has been up until recently, that the higher the HDL, the lower the risk. So traditionally, physicians have been using very high HDL levels as a marker of a really healthy cholesterol profile.Fischman: That’s the researcher behind some of the newer studies.Quyyumi: My name is Arshed Quyyumi. I'm professor of medicine in the Division of Cardiology at Emory University School of Medicine in Atlanta, Georgia.Fischman: He did a study of more than 400,000 people in the U.K., people without other predisposing risk factors for heart disease. For men, cardiac and other disease risks went up if their HDL levels were under 40—or over 80. For women, the risk climbed once HDL levels topped 100.Lewis: When you say “climbed,” how much of a risk are we talking about? A few small percentage points, or a much bigger increase?Fischman: Excellent question, and I asked Quyyumi about the amount of extra risk that people faced.
Liu, C. et al. (2022) “Very high high-density lipoprotein cholesterol levels and cardiovascular mortality,” The American Journal of Cardiology, 167, pp. 43–53. DOI: 10.1016/j.amjcard.2021.11.041 Trimarco, V. et al. (2022) “High HDL (high-density lipoprotein) cholesterol increases cardiovascular risk in hypertensive patients,” Hypertension, 79(10), pp. 2355–2363. DOI: 10.1161/hypertensionaha.122.19912
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