Everybody worries. Parents worry about their children, wives worry about husbands. Barack Obama must have worried for months about Hillary Clinton, and all of us are worried about the rapidly rising cost of food and fuel.

But is worry necessary? Traditional wisdom holds that whatever human beings do, it must be for good reason. We may not like worrying, but, so the theory goes, there must be some survival advantage in it.

Is this true? Maybe 10 per cent of what we worry about really matters; the rest is stuff that never happens (the sky is falling!) or already has happened so we can't do anything about it (losing money on the stock market). Studies show that people who worry a lot are generally less effective than those who don't; they get less work done and are often less happy. In experimental tasks, worriers are slower to respond than non-worriers (presumably because worrying burns off mental energy that would be more effectively applied elsewhere), and one recent laboratory study at Yale and Pennsylvania State University has shown that the mere opportunity to worry for five minutes is enough to bring down a person's mood.

Evolutionary products aren't that smart

Broadly speaking, it's a fallacy to presume that all of evolution's products are intelligently designed. Evolution has no foresight - and no hindsight, either. When it stumbles on a solution it tends to stick with it, even if that solution might be less than stellar.

Take, for instance, the human spine. We are stuck with a single-column spine, not because it is ideal but simply because evolution happened to stumble on a mediocre design and, once there, that design became entrenched. From the perspective of an engineer, our spine is clumsy and inelegant; it gets the job done, but hardly in the best way possible. In short, it is what engineers call a kluge. The brain circuits that lead us into worry, stress and anxiety may be similarly clumsy, circuits that are adequate, but with serious vulnerabilities.

At its most useful, worrying is about mobilising us for action. We recognise a threat - perhaps a predator in the distance - and our levels of cortisol, a hormone released in response to stress, rise and we prepare for fight or for flight.

The trouble is that evolution forgot to include an “off” button. Preparing for fight-or-flight makes sense when we're talking about ancestors who needed to decide how to deal with immediate threats such as predators, but not, for the most part, with the sort of persistent situations that drive modern human beings to distraction.

Most worry, at least today, isn't about immediate threat, it's about long-term threat. What will happen if I lose my job? Will my partner ever really love me? Such questions are worth consideration but are not the sort of thing that can be solved in an instant.

In these circumstances, elevated cortisol levels do us no good. The hormone primes our body for physical activity if we, say, have to sprint from danger. However, it also acts to dampen the immune system, which may make us susceptible to infections. What we really need to do is relax and think clearly, but evolution often leads us in the opposite direction; worry often breeds anxiety, paralysis, depression, rather than creative solutions. A recent study from University College London of 542 adults with an average age of 60, found that those who engaged with their problems and sought social support had lower cortisol levels than those who did not.

The word worry comes from a Middle English word “wyrgan”, which means to strangle. And that's what worries often do; they seize us by the throat until we can't think about anything else. When worry takes on a life of its own, it becomes a huge and often pointless drain on our time and energy. Worse, chronic worry may take a toll on our hearts. Earlier this year a study from Cambridge University linked banking crises to an increased number of heart attacks, perhaps because chronic worry and stress can lead people to drink more, smoke, eat too much and take less exercise.

Worry, it has been said, is often like a rocking chair: it gives you something to do, but it doesn't necessarily get you anywhere. Evolution may have given us the opportunity to worry, but that doesn't mean we should take the bait.

How to deal with worries

Worries largely fall into three groups: those that demand immediate attention (“alarm bells”); those that prompt us to focus on continuing problems; and those that anticipate future threats.

Alarm bells are serious business. If you see smoke and are worried about whether there is a fire, by all means drop everything and figure out what needs to be done.

Reminder worries, such as taking the children to their swimming classes or remembering to send Dad a card for Father's Day, should be left to a calendar; use computers or daily planners to offload anxiety.

Future problems deserve due consideration, but don't let them take over your life. Set aside a particular time each day to worry about long-term risks, such as financial difficulties and what you can do about them. Don't let yourself think about those issues at other times.

Prepare, but don't panic It's good to think ahead, but useless to worry about things beyond your control. Don't waste mental energies on problems you can't do anything about.

Become mindful Worry mostly comes from automatic, unmonitored thought. If you find yourself worrying about the same thing twice in a day, ask yourself if you are worrying about something you can change. If not, force yourself to move on. Think about something different.

Making decisions Don't kill yourself trying to make perfect decisions Every decision takes mental energy. It's OK to think long and hard about whether to get married, move to a new city, or to have a child, but when you're deciding between that Saab and a Volvo, don't give yourself more than a few days. Chocolate and vanilla are both nice and, in the final analysis, it won't matter which one you've eaten.

每個人都會焦慮。父母為孩子操心，妻子為丈夫擔憂。奧巴馬肯定為希拉里。克林頓憂心了數月了，而我們所有人都在為糧油價格快速攀升而焦慮不已。

但一定要焦慮嗎？傳統名言認為，不管人類要做什么，都應該是為了好的理由。我們可能不喜歡焦慮，不過，正如理論所說，這其中肯定有一定的生存好處。

真的嗎？也許我們所憂慮的事情中10%是真有其事；其余的通常就是杞人憂天了！或者是已經發生我們根本不能做什么事情來改變的，比如在股市虧錢了。研究表明無憂無慮的人來說，焦慮過多的人常效率較低，完成工作較少，人通常也不快樂。在實驗中，焦慮者比無憂無慮者反應更慢（這可能是因為焦慮本身消耗了精神能量吧，這些能量本來可以用在別處實現更高效率的），而最近來自耶魯和賓夕法尼亞大學的一項試驗研究表明，5分鐘的焦慮足夠讓人情緒低落。

進化的結果并不那么聰明

一般地說，假定所有的進化結果都是聰明地設計的顯然是個謬論。進化本身并沒有遠見，也沒有后見知明。當進化停留在一種解決辦法上時，通常就會執著于此，哪怕這個解決辦法并不是一流的方案。

      拿人體的脊椎來舉例吧。我們只有一條脊椎，并不是因為這是最理想的，僅僅是因為進化恰恰就停留在這樣一個平凡的設計上，一旦存在，這種形式就成為確立無疑的。站在工程師的角度來看，我們的脊椎又笨拙又不優雅。倒是完成了進化，但幾乎不是可能的最佳方式。總之，它不過是工程師們稱之為的kluge。把我們帶入憂心，沮喪，焦慮的腦電流可能（與進化的脊椎一樣）同樣笨拙，電流是適當的，但存在嚴重的弱點。

焦慮的最大作用是調動我們立即付諸行動。我們認識到威脅-也許是遠處的一個掠奪者，為響應這種壓力，釋放出荷爾蒙，隨之我們的皮質淄醇水平上升，我們就做好了戰斗或者是逃跑的準備。

麻煩就是，進化似乎忘記要設計一個取消（關閉鍵）了。當我們談到我們的遠祖時，所謂的做好準備戰斗或逃跑還有點意義，因為他們需要決定怎樣應付當前的威脅，就像面對掠奪者時；不過，對大部分情況來說，一直以來持續的情況是，現代人類被驅往娛樂上，這時候就沒有什么意義了。

至少今天來說，焦慮并不是關于緊迫的威脅的，而是關于長期威脅的。比如老是想著：如果我失業了怎么辦呢？我的配偶真正愛我嗎？這樣的問題值得考慮，但并不是可以立即解決的事情。

在這些情況下，皮質醇水平上升對我們沒有好處。加入說，我們得趕快脫離危險，荷爾蒙可以幫助我們的身體立即做好行動的準備。不過，它也會促使我們消除我們的防御系統，這會讓我們容易受感染。其實我們真正需要做的是放松下來考慮清楚，而進化結果卻常常把我們帶往相反的方向。擔心通常帶來焦慮，接著是麻木，然后是消沉，而不是富有創意的解決辦法。倫敦大學對平均年齡在60歲左右的542位成年人所作的一項最新研究發現，致力于尋求社會支援來解決自身問題的人比那些不尋求支援的人的皮質醇水平較低。

“焦慮(Worry)”這個詞來源于中古英語單詞“wyrgan”,意思是扼死。這正是焦慮的通常結果。焦慮扼住我們的喉嚨，最后我們不能想到其他任何事情。當焦慮占據了生活的全部時,就變成一個巨大而沒有意義的消耗，無端的消耗我們的時間與精力。更糟糕的是，持久地焦慮會給我們的心臟造成損傷。年初劍橋大學的研究發現銀行危機帶來更多的心臟病，也許是因為長久的焦慮和抑郁可導致人們酗酒，吸煙，暴食，更少鍛煉。

據說，焦慮就像一把搖擺不停的椅子，它讓你總是有事可做，但又讓你碌碌無為。也許進化給了我們焦慮的機會，但并不意味著我們應該背上這份折磨吧。

怎樣應付焦慮癥

焦慮大部分可以分成三類：需要立即注意的（警鐘類），一類是促使我們關注在持續的問題上，還有一類是預期未來的威脅。

警鐘類焦慮：最嚴重的一類。如果你看到冒煙就擔心會不會是起火了，那么放下所有的事情，趕快斷定要怎么做。

提醒類焦慮：類似送孩子去上游泳課或要記住給父親送父親節卡片這樣的事情，可以在日歷上注明，用計算計或者日常計劃可以解除這類焦慮。

對未來問題的焦慮：值得正當（程度）的考慮，但不能讓其控制了自己的生活。每天留出一個特定的時間來考慮長期的風險，比如財務困境，想想對此有什么辦法。不讓自己在其他時間考慮這些問題。

預先準備，但不要恐慌：能事先想到當然很好，但為自己控制能力之外的事情去擔心就沒有必要了。不要再自己能力范圍之外的問題上浪費精力。

怎樣應付焦慮癥

焦慮大部分可以分成三類：需要立即注意的（警鐘類），一類是促使我們關注在持續的問題上，還有一類是預期未來的威脅。

警鐘類焦慮：最嚴重的一類。如果你看到冒煙就擔心會不會是起火了，那么放下所有的事情，趕快斷定要怎么做。

提醒類焦慮：類似送孩子去上游泳課或要記住給父親送父親節卡片這樣的事情，可以在日歷上注明，用計算計或者日常計劃可以解除這類焦慮。

對未來問題的焦慮：值得正當（程度）的考慮，但不能讓其控制了自己的生活。每天留出一個特定的時間來考慮長期的風險，比如財務困境，想想對此有什么辦法。不讓自己在其他時間考慮這些問題。

預先準備，但不要恐慌：能事先想到當然很好，但為自己控制能力之外的事情去擔心就沒有必要了。不要再自己能力范圍之外的問題上浪費精力。

時刻留心：焦慮更多來自沒有監視的自動的想法。如果你發現自己為同一件事一天考慮兩遍，問問自己你擔心的事你能改變嗎?如果答案是不能，那么就迫使自己不要想了。考慮一下其他事情好了。

做出決定：不要讓自己精疲力竭地來作出完美的決定。每一個決定都耗費精力的。對是否結婚或搬去另一個城市或者是要孩子這樣的問題考慮成熟些謹慎些是好的。但在決定是買薩博還是沃爾沃車這樣的問題上，給自己的考慮時間不要超過幾天。巧克力還是香草布丁都不錯，在最后的分析對比中，到底你吃的是什么并不那么重要。