研究发现，每天吃一个牛油果可以降低“坏”胆固醇

研究发现，每天吃一个牛油果可以降低“坏”胆固醇

We’ve all heard the old saying, “An apple a day keeps the doctor away.” According to a new study, however, the same may be true for avocados — at least when it comes to lowering “bad” cholesterol levels.

我们都听过一句老话:“一天一苹果，医生远离我。”然而，根据一项新的研究，牛油果可能也是如此——至少在降低“坏”胆固醇水平方面是如此。

The study, conducted by researchers at Penn State University and published in the Journal of Nutrition, suggests that eating one avocado a day can lower levels of low-density lipoprotein (LDL), the type of cholesterol considered to be “bad.” High levels of LDL can build up within blood vessel walls, sometimes causing a stroke or heart attack, per the Mayo Clinic.

宾夕法尼亚州立大学(Penn State University)的研究人员进行的这项研究发表在《营养学杂志》(Journal of Nutrition)上。研究表明，每天吃一个牛油果可以降低低密度脂蛋白(LDL)的水平。根据梅奥诊所的说法，高浓度的低密度脂蛋白会在血管壁内积聚，有时会导致中风或心脏病发作。

On the other hand, high-density lipoprotein, or HDL, is often regarded as “good” cholesterol.

另一方面，高密度脂蛋白通常被认为是“好的”胆固醇。

For the study, researchers recruited 45 adults who were either overweight or obese. For the first two weeks, participants ate a diet that “mimicked an average American diet,” which allowed all those involved to “begin the study on similar nutritional ‘footing,’” according to a news release regarding the study.

在这项研究中，研究人员招募了45名超重或肥胖的成年人。根据一份关于这项研究的新闻稿，在前两周，参与者的饮食“模仿了美国人的平均饮食”，这让所有参与者“以类似的营养‘基础’开始研究”。

Later, the participants were separated at random into three groups. Each group either followed a low-fat diet, a moderate-fat diet, or a moderate-fat diet that also involved eating an avocado each day.

之后，参与者被随机分为三组。每一组要么遵循低脂饮食，中等脂肪饮食，或中等脂肪饮食还包括每天吃一个牛油果。

Five weeks later, those who ate an avocado each day “had significantly lower levels of oxidized LDL cholesterol than before the study began or after completing the low- and moderate-fat diets,” per the news release. “Participants also had higher levels of lutein, an antioxidant, after the avocado diet.”

五周后，那些每天吃一个牛油果的人“氧化的低密度脂蛋白胆固醇水平明显低于研究开始前或完成低脂肪和中等脂肪饮食后的水平，”新闻稿中写道。“吃了牛油果之后，参与者体内的叶黄素(一种抗氧化剂)含量也更高。”

In other words, the researchers determined that avocados may be able to lower oxidized LDL particles. Oxidation can negatively affect the human body.

换句话说，研究人员认为，牛油果可能能够降低氧化的LDL颗粒。氧化会对人体产生负面影响。

“When you think about bad cholesterol, it comes packaged in LDL particles, which vary in size. All LDL is bad, but small, dense LDL is particularly bad. A key finding was that people on the avocado diet had fewer oxidized LDL particles. They also had more lutein, which may be the bioactive that’s protecting the LDL from being oxidized,” said Penny Kris-Etherton, distinguished professor of nutrition, in a statement.

“当你想到坏胆固醇时，它会以LDL颗粒的形式出现，LDL颗粒大小不一。所有的LDL都是有害的，但密度小的LDL尤其有害。一个重要的发现是，食用牛油果的人体内氧化的低密度脂蛋白颗粒较少。他们也有更多的叶黄素，这可能是保护LDL不被氧化的生物活性物质。

“A lot of research points to oxidation being the basis for conditions like cancer and heart disease,” Kris-Etherton added. “We know that when LDL particles become oxidized, that starts a chain reaction that can promote atherosclerosis, which is the build-up of plaque in the artery wall. Oxidation is not good, so if you can help protect the body through the foods that you eat, that could be very beneficial.”

克里斯-埃瑟顿补充说:“许多研究表明，氧化是导致癌症和心脏病等疾病的基础。”“我们知道，当低密度脂蛋白颗粒被氧化时，会引发连锁反应，从而促进动脉粥样硬化，即动脉壁上斑块的积聚。”氧化是不好的，所以如果你能通过吃的食物帮助保护身体，那将是非常有益的。”

That said, Kris-Etherton did note that more research is needed to understand the more nuanced health benefits of avocados, which are already known to be full of important nutrients – such as vitamin K and potassium – as well as fiber, heart-healthy fatty acids and antioxidants.

尽管如此，克里斯-埃瑟顿还是指出，需要更多的研究来了解牛油果对健康更细微的益处。牛油果富含重要的营养成分，如维生素K和钾，还有纤维、有益心脏健康的脂肪酸和抗氧化剂。

“They are such a nutrient-dense package and I think we’re just beginning to learn about how they can improve health,” she added.

她补充说:“它们营养丰富，我认为我们刚刚开始了解它们是如何改善健康的。”