考研英语外刊阅读
第一段：
Researchers seem to have discovered a fountain of youth,but it’s a tough sell:eating far fewer calories.This is apparently not about losing weight but has more to do with the benefits of not over-fueling your cells.Scientists have found that cutting way back on food can double the lifespans of mice and add years for monkeys.And now there’s new evidence,from a big clinical study called Calerie,of a possible effect in humans based on a two-year trial that changed molecular markers of aging in calorie-deprived subjects.
研究人员似乎发现了青春的源泉，但这个说法很难让人接受：摄入更少的卡路里。这显然不是为了减肥，而是为了不让你的细胞营养过剩。科学家已经发现，在很早以前就减少食物摄入量可以让老鼠的寿命翻倍，并让猴子的寿命延长。
第二段：
The subjects started with a body mass index between 22 and 28,which is considered normal to overweight.They tended to lose weight early and then plateau.But even after they stopped getting thinner,they kept getting healthier according to blood measurements,a finding published in a previous paper.
研究对象的体脂数最初在22到28之间，人们认为这是正常到超重的区间。他们通常初期减肥，然后进入平稳期。此前一篇发表论文中的发现指出，根据血液测量结果，即使他们停止变瘦之后，仍然能变得更健康。
第三段：
The new study analyzed the same subjects for what the researchers call aging clocks.Studying these molecular timekeepers requires tracking changes in something called epigenetic markers—small chemical pieces that stick to and block certain pieces of DNA from being activated.Our epigenetic markers can slowly move around and get scrambled over time,something scientists have learned to use to estimate age.
这项新的研究对相同研究对象分析了研究员所称的“老化时钟”。研究这些分子计时器需要追踪一种被称为表观遗传标记物的变化——这是一种粘附并阻止特定DNA片段被激活的小化学片段。我们的表观遗传标记物会随着时间的推移慢慢移动，并且发生不规则生长，科学家已经知道利用这种物质来估计年龄。
第四段：
What this study focused on was rate of aging,said epidemiologist and study co-author Daniel Belsky of the Columbia School of Public Health.They saw signs that the calorie cutters’cells were aging a tiny bit more slowly.It was a small difference overall,but might add up to something meaningful if the subjects kept at it.Das,of Tufts,said she’s working on a follow-up study to see whether the subjects sustained the new eating patterns and how that affected them.
哥伦比亚公共卫生学院的流行病学家和研究合著者丹尼尔·贝尔斯基说，这项研究关注的重点是衰老的速度。他们发现有迹象表明，减少卡路里摄入的人体内细胞的老化速度稍微慢了一点。总的来说，它的差异很小，但如果研究对象坚持下去，累积起来可能就很有意义。塔夫茨大学的达斯说，她正在进行一项后续研究，看看研究对象是否能把新的饮食模式坚持下去，以及对他们的影响。
第五段：
Kraus,the cardiologist,laid out some reasons why eating less might slow aging.The energy-producing part of your cells,called the mitochondria,get overworked when you eat a lot.“It’s like running your car engine hot,”he said.Toxic byproducts get produced—reactive oxidative species,also known as free radicals.So cutting calories can reduce the load on those mitochondria,he said.Exercise can have a similar effect and helps the mitochondria burn the metabolic trash.
心脏病专家克劳斯列举了一些少吃可能延缓衰老的原因。当你吃得太多时，你的细胞中名为线粒体的可以产生能量的部分，会工作过度。“这就像让你的汽车引擎过热一样，”他说。这一过程会产生有毒的副产物——反应性氧化物质，也称自由基。他说，因此减少热量摄入可以减轻线粒体的负担。运动也有类似的效果，可以帮助线粒体燃烧代谢垃圾。
