吃鹽也會使人上癮 竟類似毒品功效
也許有人會對接下來的這條新聞產生疑惑。
But researchers claim that salt is addictive in the same way as cigarettes or hard drugs, with the craving triggering the same genes, brain cells and brain connections.
不過研究人員聲稱，我們平時所食用的鹽就如同菸草或硬性杜平一樣會讓人上癮，因爲它們都能刺激相同的基因，激發大腦細胞對此產生渴望和依賴。
The finding could help explain why many find it so hard to cut back on salt, despite warnings about dangers to blood pressure and heart health.
這想法向或許能解釋這樣一種現象，再被告知了匯兌血壓和心臟產生健康的威脅，不過還是有很多人很難將食物中的鹽量降低。
For the study, Australian and American scientists kept some mice on low-salt diets and gave others a salt drip.
澳大利亞和美國的科學家合力完成了這項實驗，他們給一部分的小白鼠低鹽的飼料，而另一部分卻加大鹽分的比重。
Activity in the creatures' brains was then compared with that in mice fed normally. They also studied the brains of mice that had been starved of salt for three days and then given salty water to drink freely.
然後將這兩批進行特殊“飲食”的白鼠的大腦活動與正常“飲食”的白鼠比較。科學家們還研究了已經三天沒有食用任何鹽分的白鼠的大腦，之後在給它們鹽水，讓其自由飲用。
When the rodents were in need of salt, brain cells made proteins more usually linked to addiction to substances such as heroin, cocaine and nicotine.
當白鼠處於對鹽有需求的狀態時，它們的大腦細胞會產生上癮的物質，該物質與通常與對海洛因、可卡因、尼古丁的上癮依賴有關聯。
Professor Derek Denton, of the University of Melbourne, said: 'In this study we have demonstrated that one classic instinct, the hunger for salt, is providing neural organisation that subserves addiction to opiates and cocaine.'
墨爾本大學的Derek Denton教授說：“在這項試驗中，我們展示了一種經典的本能，對於鹽分的‘飢渴’，神經組織的表現就如同對於鴉片和可卡因的上癮一樣。”
The study also revealed that after salt was taken, the brain believes it has received its fix well before it should be physically possible.
研究還揭示了，一旦攝入了鹽，大腦便認爲已經得到了滿足，這也許要先於身體真正對其進行吸收。
In other words, the changes caused by salt cravings disappeared well before the salt could have left the gut, entered the blood and got to the brain.
換句話說，由於對鹽的渴求所產生的變化在鹽分離開腸道、進入血壓和大腦之前便已經消失了。
Professor Denton said: 'It was amazing to see that the genes that were set "off" by the loss of sodium were already beginning to get back to the original state within ten minutes.
Denton教授說：“基因在因爲缺鹽而產生的變化在補給之後便能在十分鐘之內恢復到原本狀態，這很是令人吃驚。”
'It is an evolutionary mechanism of high survival value because when an animal is depleted of water or salt it can drink what it needs in five to ten minutes and get out which makes it less susceptible to predators.'
“這是生物進化中的一種生存優勢，在缺水或缺鹽的狀態得到補給之後，在五到十分鐘便能恢復到正常狀態，這將不會留給獵食者可乘之機。”
The researchers said that the importance of salt to overall health means that cravings for it form 'an ancient instinct' deeply embedded in the brain. This may explain why we find salty foods so tasty.
研究人員表示，對於整體的健康來說，鹽分的重要性以及由此產生的渴望是一種“原始的本能”，被深深的刻進了人類的大腦之中，這也就是爲什麼我們會認爲高鹽的食物十分美味。
