菜太淡沒有味道？加一勺鹽！你做菜時也用過這一招嗎？鹽被稱為百味之首，但世界衛(wèi)生組織建議，每人每天食鹽攝入量不要超過5克，但如果攝入量極低也對身體有害。來看看科學家們是怎么說的。

Salt consumption exceeds national and World Health Organization guidelines in most countries, but only the highest-sodium diets, such as in China, are linked to clear health risks, researchers said.

大多數(shù)國家居民的鹽攝入量都超過國家和世界衛(wèi)生組織指導量，不過，研究人員表示，只有鈉含量非常高的飲食——例如中餐，才明確與健康風險有關(guān)。

Only individuals with a daily salt intake of at least 12.5 grams -- about two-and-a-half teaspoons -- were associated with increased blood pressure and a greater risk of stroke, they reported in The Lancet, a medical journal.

研究發(fā)現(xiàn)，只有每日鹽攝入量達到12.5克（約兩茶勺半）以上的個體才伴有血壓增高、中風可能性加大的危險。該研究結(jié)果發(fā)表在醫(yī)學刊物《柳葉刀》上。

WHO recommends capping salt consumption at five grams per day, but this target is not known to have been achieved at a national level anywhere in the world, the survey of more than 90,000 people spread across 300 distinct communities in 18 countries found.

調(diào)查發(fā)現(xiàn)，盡管世衛(wèi)組織建議每日鹽攝入量不超過5克，但目前世界上還沒有哪個國家能達到這一目標。超過9萬人參與了這項調(diào)查，他們來自18個國家的300個不同社區(qū)。

"We should be far more concerned about targeting communities and countries with high average sodium intake -- above five grams (equivalent to 12.5 grams of salt), such as China -- and bringing them down to the moderate range" of 7.5 to 12.5 grams of salt, said lead author Andre Mente, a professor in the Population Health Research Institute at McMaster University in Canada.

研究報告的主要作者、加拿大麥克馬斯特大學人口健康研究所的安德烈·門特教授說：“我們應(yīng)該更加關(guān)注平均鈉攝入量高的團體和國家，即日均鈉攝入量超過5克（相當于12.5克鹽）國家，比如中國，應(yīng)將他們的攝入量降至適當范圍內(nèi)，即日均攝入7.5克至12.5克食鹽?！?/p>

One gram of sodium equals 2.5 grams of salt.

1克鈉相當于2.5克食鹽。

Four-fifths of the groups examined in China had average daily salt intake of 12.5 grams, whereas in other countries 84 percent ingested between 7.5 and 12.5 grams.

在參與調(diào)查的中國人中，有五分之四日均鹽攝入量為12.5克，而其他國家84%的人日均鹽攝入量在7.5克至12.5克之間。

"Our study adds to growing evidence that, at moderate intake, sodium may have a beneficial role in cardiovascular heath, but a potentially more harmful role when intake is very high or very low," he said in a statement.

安德烈·門特在聲明中表示：“我們的研究進一步證明，在適量攝入的情況下，鈉對心血管健康有利，但是如果攝入量極高或極低的話，可能存在更為有害的影響?！?/p>

The human body needs essential nutrients such as sodium and many vitamins, but the ideal amount remains subject to debate.

人體需要鈉和多種維生素等必要營養(yǎng)物質(zhì)，但這些物質(zhì)的理想攝入量還沒有定論。

The study examined urine and blood samples, along with health records, for 95,767 women and men monitored over an eight-year period.

研究人員在8年的時間里對95767名男女進行了監(jiān)測，檢驗了他們的尿液和血液樣本以及健康數(shù)據(jù)。

Nearly 3,700 of the participants died during that time and 3,543 had "major cardiovascular events".

研究期間，近3700名參與者離世，3543人患有“嚴重心血管疾病”。

Experts not involved in the study were sharply critical of its methodology. The technique for collecting urine samples is notoriously unreliable, they noted. And the fact that it was an observational study -- as opposed to clinical trials -- means that no firm conclusions can be drawn as to cause-and-effect.

未參與這項研究的專家嚴厲批評了這種方法論，他們指出，搜集尿液樣本的方法非常不可靠，且這種方法實際上是觀察性研究，而不是臨床試驗，這意味著無法得出確定的因果結(jié)論。

Most controversial was the suggestion that low sodium intake may, in fact, provoke heart disease.

研究認為，低鈉攝入量實際上會引發(fā)心臟疾病，大多數(shù)爭議也正集中于此。

"There are no known mechanisms that could explain this observation," commented Tom Sanders, professor emeritus of nutrition and dietetics at King's College London.

倫敦大學國王學院營養(yǎng)學和飲食學榮譽教授湯姆·桑德斯評論稱：“現(xiàn)有機制無法解釋這種觀察現(xiàn)象?！?/p>

"Sodium is an essential nutrient but the requirement is very low at about 0.5 grams (1.25 grams of salt) per day."

“鈉是一種必要營養(yǎng)成分，但是需求量非常低，每天約0.5克（相當于1.25克食鹽）?！?/p>

Ageing populations, he added, should still be advised to restrict the addition of salt to food.

他補充說，還是要建議老年人控制鹽攝入量。

中國人每天到底吃了多少鹽？

2016年，研究人員在《美國醫(yī)學會雜志》上報告說，盡管中國人的平均鹽攝入量自2000年以來不斷下降，但仍遠高于世界衛(wèi)生組織推薦的最大鹽攝入量。

領(lǐng)導這一研究的中國國家食品安全風險評估中心技術(shù)總師吳永寧告訴新華社記者，中國自1990年以來先后開展了5次總膳食研究調(diào)查，前4次覆蓋12個省份，代表中國人口的46%，第5次總膳食研究從2009年開始到2013年結(jié)束，覆蓋21個省，代表中國人口的近80%。

他們對2000年第3次總膳食研究以來中國人對食鹽和鈉的消費量進行了分析。研究表明，從2000年到2009年的10年間，中國居民食鹽消費量從11.8克/天下降到9.2克/天，下降了約22%。

吳永寧說，如果能保持這樣的速度，中國有可能實現(xiàn)世界衛(wèi)生組織提出的，到2025年降低鹽攝入量30%的目標。但問題在于，成品食鹽只是中國人攝入鈉的來源之一，醬油等調(diào)味品以及咸菜等加工食品含有大量鹽分，但通常沒有計入鹽攝入量調(diào)查中。

來源：法新社、參考消息網(wǎng)、新華社

翻譯&編輯：yaning