喀麥隆 吃泥土的習俗與吃土成癮的人(中)
Half an hour later, I walk out of a shop selling “African groceries” carrying a stone that had cost me 99p. I gingerly put a small piece in my mouth. The grit sucks all of the water from my tongue, forming a paste that sticks to the roof of my mouth like peanut butter.
果然，半個鐘頭以後，我懷揣着一塊耗資99便士的泥巴,從一家號稱售賣“非洲食品雜貨”的鋪子裏邁步走出。隨後，我輕手輕腳地掰開一小塊放到嘴裏。霎時間，土裏的沙礫吸乾了我舌頭上的全部水分，接着就跟塊漿糊似的粘在我口腔頂部，那質感有點像花生醬。
I briefly entertain the thought that it tasted a little bit like smoked meat, before deciding that no, actually it tasted much more like dirt.
剎那見，我萌生出一個念頭，感覺它嚐起來有一點兒像煙燻肉。但馬上，我就槍斃了這個想法，說實在的，它嚐起來真正就是泥土的味道啊。
I wondered what it is that gets so many people hooked.
所以，我就納了悶了，爲什麼有這麼多人吃土吃上癮。
“Everyone has their reasons,” says Monique, another Cameroonian student. “Simple desire is one, or else to treat nausea and stomach pain. The clay calms the pain by acting as a gastric dressing.”
莫妮克（Monique）說：“每個人都有自己的原因”，她是另外一名來自喀麥隆的學生，“有些人純粹是爲了滿足自己的慾望而吃土，還有些人是爲了治療反胃噁心和胃痛而吃土。黏土到了胃裏，會形成一層保護膜，進而緩解胃的疼痛。”
Could this be it? Instead of an illness, is geophagy a treatment?
果真如此嗎？難道食土癖非但不是一種怪病，反而還是一種治病的療法？
In fact, three key explanations have been proposed for why people eat dirt, and Monique’s answer touches on one of them.
事實上，對於人們吃土的原因，已有三種主要的解釋性論述，而莫妮克的回答便涉及到了其中之一。
Not all dirt is created equal. Kaolin belongs to a specific group of clay minerals, and these seem to be the most popular when people crave a mouthful of earth.
不同的泥土生成的方式也有所不同。高嶺土從屬於一種特別的礦物質黏土類型，而這些礦物質黏土似乎也是最受食土族羣喜愛的黏土。
Clay is very good at binding to things, so when Monique talks about it calming gastric pains, it could be doing just that by binding with or blocking harmful toxins and pathogens in the digestive system.
黏土是非常好的粘合材料。所以，當莫妮克提到吃土緩解胃痛時，它的作用原理應該就是：黏土進入消化系統後吸附有害有毒物質、阻礙病原體入侵。
Experiments with rats andobservations of monkeys indicate that other animals may seek non-food substances to combat ingested poisons, and various traditional food preparation practices involve mixing food with clays to extract toxins andmake it palatable. Acorns are generally unpleasant to eat, for example, but the traditional production of acorn bread in both California and Sardinia involves grinding the nuts up with clay that seems to reduce the concentration of unpalatable tannic acid they contain.
根據小白鼠實驗和對猴子的觀察，專家發現除了人類，其他動物也會通過攝入非食物類物質來對抗體內的毒素。而在各種傳統的食物烹製過程中，都有這麼一個步驟：在食物中混合些污泥，進而將食物中的毒素提取出來，同時讓食物更加美味可口。比如說，橡子其實是味道極澀的一種堅果，但在美國加州和意大利的撒丁島，橡子麪包是一種傳統的食物。爲了減少橡子中苦澀的丹寧酸的含量，人們用泥塊將橡子的果仁碾碎，從而使橡子麪包更可口。
The second hypothesis is perhaps more intuitive: clay could provide nutrients that are not present in conventional food items. Anaemia is often associated with geophagy, so perhaps eating iron-rich soil is an instinctive attempt to remedy iron deficiency.
而第二個猜想或許更爲直觀：黏土可以爲我們提供別的傳統食物沒有的營養物質。貧血症常常和食土癖聯繫在一起，而對於同時有貧血症和食土癖的人來說，含鐵量豐富的泥土或許就是他們福音。
There’s also a suggestion that geophagy is a response to extreme hunger, or micronutrient deficiencies that make non-food items attractive. This hypothesis is non-adaptive, meaning it fits with the idea that eating earth is a negative behaviour with no benefits.
另外一個意見則認爲，食土癖是在極度飢餓時產生的一個反應，又或許是人體微量營養素的缺乏導致人們對非食物類物質產生食慾。這一假設認爲吃土是非適應性的行爲（即生物體與環境表現不適合）。換言之，這一假設認爲吃土是一個負面的行爲，並不能給人帶來任何好處。
The first two hypotheses, on the other hand, suggest adaptive reasons for geophagy, and they go some way to explaining its distribution, too.
前兩種假設則與之相反，認爲食土癖存在適應性原因，而且它們也解釋了食土習俗在熱帶地區相對盛行的原因。
“We predicted that it would happen most in the tropics, because that’s where there is the greatest density of pathogens,” says Young. Furthermore, children and pregnant women are two groups that might need extra nutrients or protection against disease, as their immune responses are weaker.
塞拉•楊指出：“我們判斷，熱帶地區是發生最多食土行爲的地區，因爲那裏是病原體最集中的地區”。而且，由於兒童和孕婦的免疫力相對較弱，他們是最需要營養和保護以抵抗疾病入侵的兩大羣體。
