托福阅读背景知识（七）

三、托福阅读背景知识：“纯素食主义”的风险

　　近几年，素食主义悄然流行，越来越多的人加入了素食者的行列。不过，近日发布在自然母亲网络的一篇文章指出，纯素食也有潜在的健康风险，比如，纯素食者患肠癌的几率更高、骨矿物密度偏低，以及更容易缺乏维生素B12等等。营养专家表示，加入纯素食者行列意味着你要花更多的时间来规划饮食结构以保证各类营养摄入均衡。如果没有精力和时间详细规划，营养专家建议不妨做一个“弹性素食者”，即大部分时间吃素，偶尔吃点肉补充动物蛋白。

　　Thinking of giving up meat from your diet? The potential health benefits of a green diet are well established, but a story by the Mother Nature Network (MNN) says there are also some potential side effects and health risks associated with a vegetarian lifestyle.

　　Could low cholesterol kill you? A study by the Honolulu Heart Program found that elderly people with a "low cholesterol concentration" had a "significant association with mortality." In addition, a 2009 review published in the American Journal of Clinical Nutrition found that while vegetarians have an overall lower rate of cancer compared with meat eaters, vegetarians do have a 39 percent higher rate of colorectal cancer.

　　Other health concerns associated with vegetarianism cited by MNN included lower bone mineral density and lower levels of vitamin B12. However, the publishers of the bone density study said the "magnitude of the association is clinically insignificant," at just around 5 percent.

　　Going vegetarian appears to have gained popularity in recent years. A recent Yahoo Sports article even examined the diet of Mixed Martial Arts (MMA) fighter Jake Shields. Though much of the media's focus has been on a worldwide trend toward bigger diets, whether that's Pizza Hut offering strange fast food mashups or yet another customer at the Heart Attack Grill proving that there is truth in advertising.

　　The lesson in these potential risk-factors seems to be that if you're going to become a vegan or vegetarian, you'll need to spend more time planning your nutritional choices to help ensure a balanced intake of vitamins and other nutrients. Though if you don't have the time or inclination for such efforts, there may be another option. University of Idaho nutritionist Katie Minor says that a "flexitarian" diet may be a viable third way.

　　"Flexitarians are people who are vegetarian most of the time, but once in a while will consume an animal protein," Minor told MNN. "The more restrictive you are with your diet, the more you'll have to closely monitor what you're consuming and the more likely your need will be to supplement. Work with a registered dietician to make sure you're not at risk for dietary deficiencies."

四、托福阅读背景知识：心态年轻的人寿命更长

　　Age-liars and birthday-deniers... you'd best learn a thing or two from those who are young at heart. People who feel younger than their actual chronological age may live longer than those who feel older than they truly are, a new study says.

　　谎报年龄、否认生日……想要变得年轻，那么你最好试着学学那些拥有年轻心态的人。一项新的研究称，那些自我感觉比实际年龄小的人可能比那些自我感觉比实际年龄大的人更加长寿。

　　Perceived age might play a role in more than just how you feel. Results from the study, published in the Journal of the American Medical Association suggest that people who feel a year or more older than they truly are could have around 41 percent greater risk for death.

　　感知年龄所起到的作用可能远远不止于你的感觉如何。从《美国医学协会杂志》(The Journal of the American Medical Association)的研究结果来看，那些感觉自己比实际年龄大一岁或好几岁的人会比一般人高出近41%的死亡风险。

　　University College London researchers looked at nearly 6,500 older adults, with an average age of 65.8 for the study. Around 70 percent of the subjects felt younger than they were, about a quarter felt their precise age and just under 5 percent felt a year or more older than they were, when asked "How old do you feel you are?"

　　伦敦大学学院(University College London)的研究人员调查了近6500名平均年龄为65.8岁的老年人。在回答“您感觉自己年龄有多大?”这个问题上，当中大约70%的老年人觉得自己比实际年龄小，约25%的人认为自己符合实际年龄，而只有不到5%的人认为自己比实际年龄大一岁或好几岁。

　　Those who felt older than they were had a higher death rate after a follow-up period of 99 months. While just 14.3 and 18.5 percent of people who felt younger or felt their age, respectively, died during those 99 months, 24.6 percent of those who felt aged beyond their years had died.

　　那些觉得自己年龄比实际大的人在接下来的99个月的随访期中死亡的可能性更高。而那些心态年轻以及心态岁数和实际年龄相当的人在接下来的99个月中的死亡可能性分别只有14.3%和18.5%，而那些觉得自己比实际年纪大的人有24.6%已经在这99个月中死亡。

　　The authors say more research is needed on the topic, but suggest it could be that those who feel "young at heart" have healthier behaviors and more resilience, giving them a stronger will to live. "Self-perceived age has the potential to change, so interventions may be possible. Individuals who feel older than their actual age could be targeted with health messages promoting positive health behaviors and attitudes toward aging," the authors write in the study.

　　作者称，还需要做更多的研究来论证这个话题，但也同时表示那些心态年轻的人有更健康的行为习惯及更好的抗打击力，使得他们有更加强大的生存意志。作者在该项研究中写道：“自我感知年龄的状况将会改变，使得实施预防措施变得可能。那些觉得自己比实际年龄大的人可以通过健康暗示来增强其对于衰老的积极行为和态度。”

　　The good news is, you can change your perception of how young you are. And other studies suggest that there could be more benefits to thinking yourself younger, besides a longer life. One recent study found that helping participants have positive feelings toward age, by showing them positive word associations, helped older adults improve in physical tasks like balancing and getting up out of a chair, in as little as four weeks. A 2013 study found that negative stereotypes of aging and poor memory can make older adults feel up to five years older, regardless of their actual mental abilities.

　　好消息是，你可以改变自己对年纪的认知。其他的研究也表明，心态年轻除了能延长寿命外，还益处多多。最近有研究发现，通过对老年人讲积极鼓舞的话，帮助他们对年龄保持乐观的心态的方式，能在短短四周内，提高老年人的身体机能：如平衡能力，从椅子上站起来的能力。2013年的一项研究发现，不论他们的实际心理能力如何，对衰老的消极刻板印象和记忆力衰退会使老年人感到自己比实际年龄老五岁。

　　There you have it. Age really should be treated as just a number.

　　现在你明白了，年龄真的应该仅仅被看成一个数字。