喀麥隆 吃泥土的習俗與吃土成癮的人(下)

That being said, there is a tendency to ascribe a special significance to pregnancy cravings. “Women see pregnancy as a time to indulge,” says Julia Hormes, assistant professor of psychology at the University of Albany in the US. “There are a lot of myths around ‘eating for two’ and giving the foetus what it needs, but really there’s not a lot of support for those ideas.”

換句話說，懷孕期間的食土癖可以被視爲在孕期產生的一種特殊渴望。“女人都會將孕期看作是一段可以縱容自己享受的時光”，美國阿伯尼大學（University of Albany）心理學副教授茱莉亞•霍爾莫斯（Julia Hormes）說道，“關於‘大的不吃，小的也得吃’以及‘給腹中的胎兒一切它需要的’產生了許多傳說，也成爲孕婦食無節制的藉口，但實際上這樣的理論並沒有太多的科學支撐。”

Hormes says in reality these cravings have a whole lot to do with culture, and not a lot to do with biology.

霍爾莫斯解釋，女人在懷孕期間產生的各種渴望其實更多地與文化聯繫在一起，與生物學並沒有太大關係。

If there are culture-specific beliefs around eating dirt, then women in Cameroon are as likely to crave it as women in Europe or North America might feel cravings for chocolate or ice cream. Just because someone craves something doesn’t mean it’s good for them.

假如說食土習俗和文化信仰有關，那麼喀麥隆的女人吃土這個行爲其實和歐美的女人愛吃巧克力別無二致。每個人都有自己特別愛吃的東西，愛吃的原因並不一定是因爲這種食物能給他們帶來什麼好處，而僅僅是因爲他們愛吃而已。

Still, the inclination towards geophagy clearly arises from somewhere, seeing as it’s found even in cultures for which it has no such significance. Studies of animals suggest an adaptive, biological explanation could be at least part of the story.

我們同時看到，在那些所謂“沒有食土習俗”的國家裏，也出現了越來越多的吃土現象。通過動物實驗，我們相信適應性和生物學的解釋至少能說明一部分人類吃土的原因。

When elephants, primates, cattle, parrots and bats engage in geophagy, for example, it is generally considered to be serving a useful purpose. Despite this, some of the same scientists who consider geophagy normal in animals still see it as abnormal in humans.

當大象、靈長類動物、牛、鸚鵡和蝙蝠都存在食土行爲，那麼我們總體上可以認爲“吃土”是有實際意義的。可儘管一些科學家同意動物吃土是正常行爲，他們仍舊認爲人類吃土是反常行爲。

Undoubtedly some cases of dirt eating do indeed involve psychiatric problems, but drawing a line is difficult. In 2000, the US Agency for Toxic Substances and Disease Registryconcluded that pathological levels of soil consumption constituted more than 500 mg per day, but even they conceded that this was an arbitrary measurement.

毋庸置疑的是，一些吃土的案例的確存在着精神疾病的問題，但如何認定吃土者是否患有精神疾病則是一個難題。美國有毒物質與疾病登記署（US Agency for Toxic Substances and Disease Registry）於2000年規定，每天500毫克的黏土食用量爲判定病態和非病態的標準——每天服食超過500毫克的黏土則爲病態——然而有關部門任性地表示，這個標準只是他們隨便定的。

“Because geophagy has been so extensively documented as a culturally-based phenomenon, I'm not inclined to view it as ‘abnormal’ behaviour,” says Ranit Mishori, a professor of family medicine and doctor at Georgetown University Medical Center. “If, however, this behaviour is associated with any clinical abnormalities, I would have a conversation about how to avoid it.”

“許許多多的文獻都表明，食土習俗是一個文化現象，因此我不贊同將其看作一種‘不正常’的行爲”，喬治城大學醫學中心（Georgetown University Medical Center）的家庭醫學教授瑞麗特•米歇裏（RanitMishori）表示，“假如說這種行爲與臨牀中所說的異常有任何關聯，那我會告訴你該如何避免。”

Clearly there are downsides to consuming dirt. The presence ofsoil-borne diseases and toxic substances in the clay is a major issue, as is the possibility that the very deficiencies supposedly cured by the practice might even be caused by them.

當然吃土的危害也是非常明顯的。土傳性病害和泥巴里的有毒物質就是一個非常大的問題，而同樣不容忽視的是，吃土本身也會導致人體微量營養素的缺乏。

Eating dirt can even become an addiction, an impulsive act hidden from others. “With geophagy, the language of substance abuse is really common,” says Young.

吃土除了會上癮，吃土這一行爲也有可能成爲一種被極力掩飾的衝動行爲。而塞拉•楊表示：“與食土癖相比，藥物濫用是一種更常見的現象”。

It’s easy to dismiss geophagy as a disgusting habit of children, a wacky pregnancy craving, or an exotic behaviour from far-away lands, but none of these approaches really do it justice. Moreover, such characterisations risk alienating people who find it difficult to explain their ‘unnatural’ desires.

人們很容易將食土癖簡單地理解爲孩子們一種噁心的習慣、孕婦們在孕期古怪的渴望，或是來自地球另一端的異國文化，但這些看法並不能真的給食土癖正名。另外，這種分類和定義的方法過於草率，會令食土的族羣更難向我們解釋他們那“反常”的愛好。

To fully grasp this phenomenon, and understand whether its effects are positive, negative or a subtle mix of the two,researchers need to undertake hypothesis-driven tests that take both biomedical and cultural factors into account.

爲了完全認識食土這一現象，並充分了解食土帶來的影響是正面、負面，或是兩者皆有，研究者們需要進行各種假說驅動的實驗，將醫學生物學和文化的因素都考慮在內。

“I’m not saying ‘everyone should be eating three spoonfuls of earth a day’”, says Young. “But we certainly don’t know enough yet to write this behaviour off entirely.”

“我不是在建議大家每天都吃三大勺的土”，塞拉•楊說，“但我們現在還沒有充分的科學研究來完整地解釋食土行爲。”