每日攝入食鹽的安全量應該是英國國民健康體系建議的兩倍

For decades experts have peppered people with warnings about the amount of salt being consumed. Scientists agree too much of it can raise blood pressure, which is linked to a higher risk of heart disease and stroke. The NHS and World Health Organisation say adults should not have over a teaspoon of salt per day - but a controversial study has suggested up to two-and-a-half teaspoons is not a danger.

幾十年來，專家一直向人們發出警告，並規定攝入食鹽的安全量。科學家認爲攝入鹽分過多會使血壓升高，而高血壓與更高的心臟病及中風風險相關。英國國民健康體系和世界衛生組織表示，成年人每天攝入的鹽分不應超過一茶匙--但一項頗具爭議的研究表明：兩茶匙半的鹽分並不會帶來危險。

The researchers also concluded eating a lot of fruit and veg may eliminate the risk of heart attacks and strokes from more than two-and-a-half teaspoons. Study author Professor Andrew Mente, of McMaster University in Canada, said: "Only in the communities with the most sodium intake... did we find a direct link between [it] and major cardiovascular events like heart attack and stroke." Sodium is the active ingredient in salt.

研究員還得出這樣的結論：每天多吃水果和蔬菜或能消除每天攝入兩茶匙半以上鹽分所帶來的心臟病和中風的風險。來自加拿大麥克馬斯特大學的研究作者安德魯·門德教授說道："只有在鈉攝入量最高的小區，我們才發現鈉與心臟病發作及中風等主要心血管疾病存在直接關聯。"鈉是食鹽中的活性成分。

They found cardiovascular problems were lower in places with a high level of potassium consumption. Foods high in potassium include fruit and veg. One problem is many processed foods are high in salt but rarely eaten with a lot of veg. The findings, published in The Lancet, involved a study of 94,000 people in 18 countries including China. Salt intake was measured with urine tests.

他們發現，在鉀攝入量較高的小區，心血管疾病的案例較低。鉀含量高的食物包括水果和蔬菜。但存在一個問題：很多加工過的食物含鹽量高，但卻很少和蔬菜搭配食用。研究結果發表在《柳葉刀》期刊上，涉及了來自18個國家（包括中國）的94000位受試者。鹽攝入量通過檢測尿液獲得。

Tam Fry, of the National Obesity Forum, said Prof Mente has been criticised in the past for his advice, so "you would be best to stay within the UK's official guidelines for the time being". Exeter University health expert Prof Rod Taylor said: "The findings were observational so cannot claim cause and effect.

國家肥胖論壇的Tam Fry表示，過去，人們總批評Mente教授的建議，所以"目前最好還是遵守英國官方指南給出的食鹽攝入量"。埃克塞特大學的健康專家羅德·泰勒教授說道："研究結果是觀察性的，並不能說明因果關係。"

"[And] they were limited to a mostly Asian population, so we don't know how widely applicable they might be." This large observational study has confirmed what is already known about high salt intake - it results in higher blood pressure and an increased risk of cardiovascular diseases. It also confirms very low salt intake can affect health badly, which is the case for most nutrients.

"而且受試者大多來自亞洲，所以研究結果的適用範圍尚不清楚。"這一大型觀察性研究已證實：鹽分攝入過多會導致血壓升高、心血管疾病風險增加。而且還證明，鹽分攝入量低會極大的影響健康，即攝入過多營養素。