In The Origin Diet, dietitian Elizabeth Somer asserts that certain cravings were central to human survival and evolution. "Fat and sugar were scarce hundreds of thousands of years ago," she writes."Fat was a precious source of calories (supplying more than twice the calories per gram of either protein or starch), and our ancestors had no need to develop an appetite shutoff valve for fat. Instead, when they found fatty food, they ate all they could get and developed an unlimited capacity to store extra calories."

     在《源頭節(jié)食》一書(shū)中，營(yíng)養(yǎng)學(xué)家Elizabeth Somer斷言：某些吃的渴望在人類(lèi)生存和進(jìn)化中曾經(jīng)起到了重要作用。"幾十萬(wàn)年以前，脂肪和糖是很缺乏的，"她這樣寫(xiě)道。 "而脂肪是熱量重要來(lái)源（每克脂肪提供的卡路里是蛋白質(zhì)或淀粉的兩倍多），因此我們的祖先在當(dāng)時(shí)并不需要控制脂肪的攝入量。相反，當(dāng)他們發(fā)現(xiàn)富含脂肪的食物時(shí)，他們有多少吃多少，并練就了一種無(wú)限儲(chǔ)存過(guò)多熱量的能力。"
 
    The quest for fat and sugar, Somer believes, is now hardwired into our brains, governed by dozens of chemicals including endorphins. Serotonin, for example, is the "feel good" chemical. When levels are low, we seem to crave sweets and carbs, which raise serotonin and improve mood. This may help explain why many women crave chocolate near their periods.

    Somer相信這種對(duì)脂肪和糖的渴望現(xiàn)已在我們的大腦中固定下來(lái)，大腦受到包括內(nèi)啡素的十幾種化學(xué)物質(zhì)的控制。譬如血清素是產(chǎn)生"好的感覺(jué)"的化學(xué)物質(zhì)。當(dāng)它的含量降低時(shí)，我們似乎就會(huì)渴望糖和碳水化合物，因?yàn)樗鼈兡芴岣哐�清素含量并改善情緒。這一點(diǎn)也許有助于解釋為什么很多女性在經(jīng)期前后會(huì)想吃巧克力。
 
    What about the cravings that many pregnant women experience? Growing research suggests that odd food yearnings - and food aversions - may protect the fetus. Some pregnant women lose the desire to drink coffee or wine and turn green at the sight of fish, meat, eggs or vegetables. Instead, they crave sweets, fruits (especially citrus) and dairy products.

    如何解釋很多孕婦對(duì)某些食物的偏好呢？越來(lái)越多的研究表明對(duì)一些奇怪食物的偏好--和厭惡--可能是出于保護(hù)胎兒的緣故。有些孕婦不再愛(ài)喝咖啡或紅酒，并且一看到魚(yú)、肉、蛋或蔬菜就倒胃口。但是，她們卻變得愛(ài)吃甜食、水果（尤其柑橘）和奶制品。
 
    One explanation: These foods are least likely to carry harmful organisms or natural toxins. "It may be your body is telling you to keep your fetus away from anything that might be toxic," says Frances Largeman, managing editor of FoodFit.com, a website promoting healthy eating habits.

    有一種解釋?zhuān)哼@些食物中含有害微生物或天然毒素的可能性最小。"可能是你的身體在教你避免使胎兒接觸可能有毒的食物，"致力于宣傳健康飲食習(xí)慣的FoodFit.com網(wǎng)站主編Frances Largeman說(shuō)。
 
    Largeman acknowledges that the theory doesn't account for why some pregnant women hunger for pickles and others for apple strudel. Cravings are difficult to explain scientifically, she says, "because people don't eat nutrients; they eat food." And everybody's preferences differ.

    Largeman承認(rèn)該理論無(wú)法解釋為什么有些孕婦愛(ài)吃泡菜，有些愛(ài)吃蘋(píng)果餡餅。吃的渴望很難從科學(xué)上解釋?zhuān)�她說(shuō)。"因?yàn)槿藗儾皇浅誀I(yíng)養(yǎng)，而是吃食物。"而各人偏好又是千差萬(wàn)別。
 
    One explanation: These foods are least likely to carry harmful organisms or natural toxins. "It may be your body is telling you to keep your fetus away from anything that might be toxic," says Frances Largeman, managing editor of FoodFit.com, a website promoting healthy eating habits.

    有一種解釋?zhuān)哼@些食物中含有害微生物或天然毒素的可能性最小。"可能是你的身體在教你避免使胎兒接觸可能有毒的食物，"致力于宣傳健康飲食習(xí)慣的FoodFit.com網(wǎng)站主編Frances Largeman說(shuō)。
 
    Largeman acknowledges that the theory doesn't account for why some pregnant women hunger for pickles and others for apple strudel. Cravings are difficult to explain scientifically, she says, "because people don't eat nutrients; they eat food."And everybody's preferences differ.

    Largeman承認(rèn)該理論無(wú)法解釋為什么有些孕婦愛(ài)吃泡菜，有些愛(ài)吃蘋(píng)果餡餅。吃的渴望很難從科學(xué)上解釋?zhuān)�她說(shuō)。"因?yàn)槿藗儾皇浅誀I(yíng)養(yǎng)，而是吃食物。"而各人偏好又是千差萬(wàn)別。
 
    Some experts think cravings are as much a reflection of our social and psychological makeup as they are of our physiological impulses. "Food adds solace to our lives," says Jeff Hampl, a spokesman for the American Dietetic Association. "Often, cravings are tied to a childhood experience and good feelings associated with it. There's a subconscious desire to replace those emotions."

    有些專(zhuān)家認(rèn)為吃的渴望除了能反映我們生理沖動(dòng)以外，還能反映我們社會(huì)和心理構(gòu)成。"食物給我們生活帶來(lái)慰藉，"美國(guó)飲食協(xié)會(huì)發(fā)言人Jeff Hampl說(shuō)。"吃的渴望常常與童年某段經(jīng)歷以及與此相關(guān)的美好情感有聯(lián)系。人的潛意識(shí)渴望恢復(fù)這種情感。"
 
    This would explain my predilection for rapini, since my mother serves it every Thanksgiving. Yet regardless of the reason, Largeman - who craves salmon sometimes - thinks you should satisfy a craving when it strikes. "A craving usually just gets worse," She says,"and it could lead to binging."

    這也許能解釋為何我會(huì)對(duì)迷迭香情有獨(dú)衷，這是因?yàn)槲覌寢屧诿總�(gè)感恩節(jié)都會(huì)做這道菜。不過(guò)，不論原因如何，有時(shí)會(huì)渴望鮭肉的Largeman認(rèn)為，當(dāng)這種渴望出現(xiàn)時(shí)，你都應(yīng)該去滿(mǎn)足它。"渴望通常只會(huì)愈演愈烈，"她說(shuō)，"它會(huì)導(dǎo)致暴飲暴食。"
 
    But most of us long for foods that aren't as nutritious as salmon. What should we do?

    但是大多數(shù)人所渴望的食物不及鮭肉營(yíng)養(yǎng)豐富。我們應(yīng)該怎么做呢？
 
    First, make sure you're experiencing a true craving - not just plain old hunger or thirst. "Sometimes people don't realize they're physically hungry," says O'Neil."If it's actually hunger, eating something reasonable such as a piece of fruit rather than a chocolate bar might do the trick."

    首先，必須確定你正經(jīng)歷一種真正的渴望--而不是普通饑渴。"有時(shí)，人們意識(shí)不到自己身體正處于饑餓狀態(tài)，"O'Neil說(shuō)。"如果真是饑餓的話(huà)，那么選擇合理的食物，譬如一片水果而不是一塊巧克力，就可以奏效。"
 
    Another option, he says, is to"leave the scene of the craving. Change your setting and engage in other things that don't involve food."

    另一個(gè)辦法，他說(shuō)，是"離開(kāi)想吃東西的場(chǎng)所。改變一下環(huán)境，做一些與吃無(wú)關(guān)的事情。"
 
    Finally, if your craving just won't be rebuffed, indulge it - judiciously."If you have a salty craving," says Largeman, "it's better to buy a single-serving bag of salt-and-vinegar chips than to buy a large bag and keep it around the house." Or try a less potent alternative - say, low-fat chocolate milk or a frozen fudge pop rather than a slab of fudge.

    最后，如果你實(shí)在無(wú)法打消吃的渴望，那么就放縱自己吧--不過(guò)要適度。"如果你愛(ài)吃咸食，"Largeman說(shuō)，"那么買(mǎi)一袋一人吃的咸醋味薯片要比買(mǎi)一大袋放在家里好。"或者還可以選擇一個(gè)低熱量的品種--譬如低脂巧克力牛奶或一瓶冰凍的乳脂軟糖汽水而不是一大塊乳脂軟糖。
 
    For years, Catherine Monk would ignore her sweet tooth, then splurge on half a pint of ice cream. Now wiser, she settles for a few table-spoons every night."That does it for me," she says. 

    幾年來(lái)，Catherine Monk一直克制自己對(duì)甜食的渴望，壓制不了時(shí)，就無(wú)節(jié)制地吃半品脫冰淇淋。現(xiàn)在，她變聰明多了，每晚只允許自己吃上幾勺。"這對(duì)我很有效，"她說(shuō)。