Review raises questions over benefits of cutting salt

LONDON, (Reuters) – In an analysis likely to fuel a  long-running debate over the health impacts of too much salt,  researchers have found no evidence that moderate cuts to salt  intake reduce the risk of developing heart disease or dying  prematurely.

In a systematic review published by The Cochrane Library,  British scientists found that while cutting salt consumption did  appear to lead to slight reductions in blood pressure, that was  not translated into lower death or heart disease risk.

The researchers said they suspected that trials conducted so  far were not big enough to show any benefits to heart health,  and called for large-scale studies to be carried out soon.

“With governments setting ever lower targets for salt intake  and food manufacturers working to remove it from their products,  it’s really important that we do some large research trials to  get a full understanding of the benefits and risks of reducing  salt intake,” said Rod Taylor of the Peninsula College of  Medicine and Dentistry at Exeter University, who led the review.

Most experts are agreed that consuming too much salt is not  good for you and that cutting salt intake can reduce  hypertension in people with normal and high blood pressure.

But while previous trials have suggested there is a blood  pressure benefit from lower salt intake, research has yet to  show whether that translates into better overall heart health in  the wider population.

High blood pressure, or hypertension, is a major risk factor  for cardiovascular diseases such as heart failure, heart attacks  and stroke, which are the world’s number one killers.

Taylor said he thought it did not find any evidence of big  benefits because the numbers of people studied and the salt  intake reductions were relatively small.

“The people in the trials we analysed only reduced their  salt intake by a moderate amount, so the effect on blood  pressure and heart disease was not large,” he said.

Many developed nations have government-sanctioned guidelines  calling on people to cut their salt or sodium intake for the  sake of their longer-term health. The World Health Organisation  (WHO) lists reducing salt intake among its top 10 “best buys”  for reducing rates of chronic disease.

In Britain, the National Institute of Health and Clinical  Guidance (NICE) has called for an acceleration of the reduction  in salt in the general population from a maximum intake of 6  grams(g) a day for adults by 2015 to 3g by 2025.

U.S. guidelines recommend Americans consume less than 2.3g  of salt daily, or 1.5g for certain people who are more at risk  for high blood pressure or heart disease.

An earlier Cochrane review of dietary advice published in  2004 could not find enough evidence to draw any conclusions  about the effects of reducing salt intake on death rates or on  rates of heart disease.

In this latest review, Taylor’s team found seven studies  that together included 6,489 participants. This gave the  researchers enough data to be able to start drawing conclusions,  they said, but even so, the scientists think they would need to  have data from at least 18,000 people before they could expect  to identify any clear health benefits.

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