The Brown Fat Has Already Helped to Reduce Weight For most people, fat is a burden. It doesn’t really matter where it appear

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问题                 The Brown Fat Has Already Helped to Reduce Weight
    For most people, fat is a burden. It doesn’t really matter where it appears, we just don’t want it. But it turns out that our bodies also make a unique form of fat tissue that behaves remarkably unlike any other: rather than storing excess energy, this fat actually burns through it. It’s called brown fat and health experts confirm for the first time that healthy adults have stores of this tissue, which researchers hope to study further as a potential new weight-loss treatment.
    Human newborns have been known to have any significant deposits of brown fat, so called because of its abnormally high concentration of dark-colored mitochondria, the engines that sustain cell activity. The primary purpose of brown fat is to regulate body temperature: the mitochondria-packed cells are designed to burn high quantities of sugar, and release that energy as heat—a mechanism that newborns rely on to keep themselves toasty.
    As people age, however, the body becomes better at regulating temperature, so brown-fat stores shrink and white fat starts to emerge. A research team in Sweden has found that healthy adults retain a sizable amount of fat in the front and back of the neck expressing the same proteins as brown fat.
    Identifying the presence of brown fat is one thing, but activating it to burn more sugar is another. Two studies confirmed that brown-fat cells become more active in the cold. But before we consider joining the Polar Bear Club, can brown fat actually cause weight loss? Brown fat may indeed allow a person to burn more calories with the same amount of consumption. On the basis of animal models, researchers calculate that 50g of brown fat could burn about 20% daily calorie an average person takes in. Leaner people tended to have more brown-fat deposits than overweight individuals. Interestingly, women were twice as likely as men to have active brown fat.
    Still, the findings don’t necessarily mean that activating brown fat leads to a slimmer waist. For one thing, the body is especially good at maintaining balance, which is why a boost in calorie-burning can often make a hunger signal and prompt people to eat more to make up for the loss. And even if drug companies could find a way to activate brown fat safely, that excess activity could throw off other metabolic systems and damage your health.
Why does brown fat get smaller with the age growing?

选项 A、Because people are getting older and older.
B、Because we have a new kind of fat-white fat.
C、Because we don’t need it to regulate our temperature any more,
D、Because human beings only have it in the front and back of the neck.

答案C

解析 事实细节题。由题干中的get smaller with the age grows定位到第三段第一句可知,随着年龄的增加,身体习惯了体温的调节,不再需要棕色脂肪了。故C“因为我们不再需要棕色脂肪调节体温了”符合文意。A“因为人们会变得越来越老”,根据本段第一句,文章提到年龄是表示随着年龄的增加会出现白色脂肪增多,棕色脂肪减少的情况,不符合题意,故排除;B“因为我们有了一种新的脂肪一一白色脂肪”,根据文意,白色脂肪的功能作用与棕色脂肪并不相同,之间没有可替代的关系,故排除;D“因为人类只有脖子前面和后面才有棕色脂肪”,这与题干之间无法构成因果关系,故排除。
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