Lancet paper blasts Cochrane salt study

Reducing salt intake can lead to 'a significant reduction in cardiovascular events' according to the re-analysis of the Cochrane data.

Commentary in The Lancet, along with a new analysis of the data, has slammed the recent Cochrane review that claimed salt reduction had no effect on strokes or heart attacks.

The re-analysis of the same data in the Cochrane review, published in the Lancet, finds a significant reduction in cardiovascular events, including a 20 per cent fall in the risk of stroke and heart attack from a reduction of 2 grams of salt per day.

The review, from Dr Rod Taylor and colleagues (reported by FoodNavigator here), stated that “Cutting down on the amount of salt has no clear benefits in terms of likelihood of dying or experiencing cardiovascular disease,” whilst a press release sent by the Cochrane Library warned: “Cutting down on salt does not reduce your chance of dying”.

“Both of these statements are incorrect,” said the authors of the re-analysis.

“Contrary to the claims by Taylor and colleagues and many press headlines, these new results, along with all the other evidence, clearly demonstrate that a reduction in the whole of the UK population and worldwide, is immensely important,” said Professor Graham MacGregor of the Wolfson Institute, and Chairman of World Action on Salt and Health (WASH), one of the authors of the re-analysis.

“In our view, Taylor and colleagues’ Cochrane review and the accompanying press release reflect poorly on the reputation of The Cochrane Library and the authors. The press release and the paper have seriously misled the press and thereby the public,” said the authors.


Professor Francesco Cappuccio, head of the World Health Organization Collaborating Centre for Nutrition at the University of Warwick said that the benefits of salt reduction are “clear and consistent.”

“The findings from the Cochrane review do not indicate that salt reduction does not reduce hypertension and cardiovascular disease. Indeed, a correct reanalysis confirms the benefits shown by previous studies,” said Cappuccio.

“Therefore, the publication does not change the priorities outlined … for a population reduction in salt intake to prevent heart attacks and strokes,” he added.

MacGregor and his colleagues added that the totality of evidence, including epidemiological studies, animal studies, randomised trials, and outcome studies, “all show the substantial benefits in reducing the average intake of salt.”

The researchers highlight that many countries have already adopted policies to reduce salt intake by persuading the food industry to reformulate food with less salt, and encouraging the population to use less salt at the table and in home cooking.

“A reduction in population salt intake will have major beneficial effects on health along with major cost savings in all countries around the world,” said the researchers.


MacGregor and his colleagues explained that the Cochrane review’s calls for further large, long term, randomised trials of salt reduction on clinical outcomes would be ‘impractical’.

“According to their own calculations, at least 2500 cardiovascular events need to be obtained to detect a 10 per cent reduction … This would require randomisation of about 28 000 participants to a low or high salt intake and then maintenance of the two separate diets for at least 5 years,” said the researchers.

“Such a trial is impractical because of logistical and financial constraints, and the ethical issues of putting a group of people on a high salt diet for so many years,” they added.

Consensus Action on Salt and Health (CASH) campaign director Katharine Jenner, added to the criticism, telling FoodNavigator that “there is no sense in waiting for further trials before progressing with an international salt reduction programme, which will immediately save many thousands of lives.”

Source: The Lancet
Volume 378, Issue 9789, Pages 380 - 382, doi: 10.1016/S0140-6736(11)61174-4
“Salt reduction lowers cardiovascular risk: meta-analysis of outcome trials”
Authors: F.J. He, G.A. MacGregor

Related News

Seventy per cent of eight-month-old babies consume too much salt in the UK.

UK study finds 70 per cent of infants consume too much salt

Salt reduction should be global priority, says expert

Salt reduction should be global priority, says expert

CASH recognises bread industry efforts on salt reduction

CASH recognises bread industry efforts on salt reduction

Mineral salts in diet could cut blood pressure, finds Finnish study

The addition of savoury aroma compounds into foods may aid salt reduction efforts.

Savoury aromas may aid salt reduction, say Unilever

'Gourmet' salt claims should be taken with a pinch of salt, says CASH

'Gourmet' salt claims should be taken with a pinch of salt, says CASH

Nu-Tek claims 30% sodium reduction for bakery salt offering

Salt intake linked to blood vessel damage and high blood pressure

Salt intake linked to blood vessel damage and high blood pressure

There is not yet enough evidence to show that reducing salt intake reduces the incidence of heart disease.

Salt reductions may not reduce heart disease risk: Cochrane review

Sodium reduction is big business

Cochrane review doesn’t change our advice on salt reduction, AHA

Sea salt contains trace levels of several important minerals

Shoppers mistakenly believe sea salt contains less sodium

High salt diet increases risk of CVD, death: Study

Low salt diet may increase anxiety levels, suggests rat study

Related Products

See more related products

Comments (11)

science Mythbuster - 26 Sep 2011 | 01:39

Evidence against rhetoric

It is good to see that at least Cochrane has not been tainted by the huge lobby against salt, we have seen the anti aslt lobby CASH and their Director Prof MacGregor conduct over recent years. The quote animal studies and epedemiology studies neither of which are as conclusive as clinical trials. In the pivotal clinical trial quoted by the anti saltistas, the DASH sodium trial, the investrigators failed to control potassium levels, the main factor influencing blood pressure's relation to salt intake. They were chronically undernourished for potassium and had different potassium intakes between groups. The sooner we get government public health departments to insists on good scientific evidence for its policies thew sooner we can start tackiling the big public health problem of blood pressure, the excess weight of our society not heading down the soidum cul-de-sac.

26-Sep-2011 at 13:39 GMT

Julie Vincent - 03 Aug 2011 | 02:40

Lack of salt

Due to the demonisation of salt we are now seeing patients with seriously low sodium blood levels requiring salt tablets to remain healthy.Escalation of hypertension and cardiac disease are relatively recent health issues in the last 50 years associated with the introduction of trans fats and increased sugars in the diet. Salt has been used as a preservative in our foods for hundreds of years with no ill effects. But now with huge investments in the low salt food industry its unlikely to change direction even with the research!

03-Aug-2011 at 14:40 GMT

Submit a comment

Your comment has been saved

Post a comment

Please note that any information that you supply is protected by our Privacy and Cookie Policy. Access to all documents and request for further information are available to all users at no costs, In order to provide you with this free service, William Reed Business Media SAS does share your information with companies that have content on this site. When you access a document or request further information from this site, your information maybe shared with the owners of that document or information.