The Weird Benefit of Eating Salty Food

吃鹽的奇妙效用

Too much salt can lead to heart disease, but there may be a healthy side to salt that hasn’t been appreciated — until now

吃太多鹽會有心血管病的疑率, 但鹽也有健康的一面呦

If you’re an average American, chances are that you’re eating too much salt. But the latest research — which, the scientists stress, is still in its early stages — hints that there may be some benefits to salt that have gone unnoticed. Salt, it seems, may be an ancient way for the body to protect itself against bacteria.

如果你是一般美國人, 你可能吃太多鹽. 但最近的研究說, 裏面的科學家強調, 雖然還在研究初期階段, 暗示鹽可能也有好處, 只是從未被發現. 鹽可能是古時候幫助身體對抗細菌的方式

Reporting in the journal Cell Metabolism, Jonathan Jantsch, from the University of Regensburg in Germany, says that salt may be an effective way to ward off microbes. In a series of studies using both mice and human cells, he and his colleagues found that levels of sodium go up around an infection site, and that without salt, bacteria tend to flourish and grow better.

科學期刊名為<細胞新陳代謝>, 德國的Regensburg大學Jonathan提到, 鹽可能可以阻擋掉細菌的一個有效物質. 在一連串對老鼠對人體細胞的實驗中, 他跟他的同事發現在感染區放些sodium, 沒有鹽, 細菌容易孳生增長很快

The discovery came about by accident, after Jens Titze, the study’s senior author, noticed that mice who had been bitten by their cage mates showed higher levels of sodium in their skin than those who were wound-free. Jantsch decided to find out whether the salt had something to do with the infection-fighting functions of the immune system.

這是無意間發現的, 這項研究的資深研究員Jens, 發現老鼠被牠們籠子的伴侶咬到, 顯示在皮膚上鈉的含量變高. Jan決定發現鹽是否與感染部份 - 跟身體免疫系統作戰有關係

He and his team conducted a series of experiments in which they subjected mouse and human cells to high levels of sodium chloride, and watched the immune cells activate. They also fed mice diets that were low and high in sodium, and then infected them with Leishmania major. The mice fed the higher amounts of sodium showed stronger immune responses to the wounds, and cleared their infections faster than the mice eating less salt. In fact, Jantsch speculates that certain skin cells may transport sodium preferentially to sites where bacterial populations are high in order to create another barrier preventing the microbes from entering deeper into the body.

他跟他的團隊做了一系列的實驗, 他們對老鼠細胞與人體細胞, 放置高劑量的氯化鈉(鹽), 然後觀察免疫細胞被啟動的狀況. 他們也餵老鼠, 在其飲食中, 加入含高劑量的鈉, 另一組放入加低劑量的鈉的食物, 再以某種細菌造成感染. 被餵以高劑量鈉的老鼠有較強的免疫反應;傷口癒合的速度也快過那些食用低劑量鹽的老鼠. 事實上, Jan推估某些皮膚細胞可能會偏好性地運送鈉到細菌聚集的地方, 以便創造一個障礙阻止微生物更深入體內

That opens the possibility that salt may be an unrecognized contributor to the immune system, and possibly a remnant from the days before antibiotics, when mammals, including humans, needed some allies in the fight against microbes. After all, salt has been used for centuries to preserve food from spoiling in bacteria’s presence, so it makes sense that evolutionarily, sodium might have also been co-opted by the body in a similar way. “I really think salt is an unappreciated factor of immunity,” says Jantsch.

這打開一個可能性, 鹽可能是個未被認知, 對免疫系統有功的物質, 可能早在未有抗生素之前的某種類似抗生素的替代品, 當哺乳類, 包括: 人, 需要與微生物對抗時會被派上用場. 反正, 鹽沿用數世紀用來保存食物, 聽來蠻合理, 進化上, 鈉以某種類似的方式在體內供應. "我真得認為鹽是一種未被肯定的免疫物質". Jan說

If that’s the case, then it may be possible to take advantage of salt-based dressings, for instance, to improve wound healing. Burn patients may benefit the most, since their skin, the first line of defense against microbes, is compromised. And for those with hyperactive immune responses, dialing down the concentration of sodium at specific areas might also be helpful. “We are interested in how this works, because it can have broad applications,” says Jantsch. “We can possibly target and boost sodium in situations where we need more salt if it’s deficient, and lower it in situations where there is salt overload and hypertension.” Already, some companies have produced wound dressings with enhanced sodium concentration as a way to help infections heal faster.

在這種狀況下, 很可能可利用鹽混合的調味料, 比方, 去促進傷口癒合. 燒燙傷的病人可能得益最多, 因為皮膚, 是抵抗微生物的第一道防線, 受傷了. 對於那些過激的免疫反應, 將鈉的劑量在某些區域調低可能有幫助. "我們對於鹽如何可起作用很有興趣, 因為它可能會有廣泛的應用." "我們可能會實驗看提高鈉的劑量在需要的區域, 調低鈉的劑量在可能過多的區域." 已經, 有些公司生產有助傷口癒合的成份, 當中就是帶有加強版的鈉萃取, 以幫助傷口癒合地更快

He stresses, however, that the results don’t mean high salt diets are now healthy — or advisable. His studies, even in mice, haven’t worked out exactly how salt in the diet affects the body’s ability to recruit the nutrient to fight infections. And to get the bacteria-fighting effect, the mice were fed a diet that was extremely high in sodium — 4%, compared to the average mouse chow which is only 0.2% to 0.3% sodium. “There is overwhelming data that tells you a high salt diet is detrimental to the heart,” he says. “We used one animal approach to look at the beneficial role of salt. So I would be hesitant to draw any conclusions for humans at this stage.” He and others are already setting up more experiments, however, to study how salt might become the next weapon in fighting infections.