A new Cochrane review on dietary salt interventions was published last week by Graudal et. al (1), an update to a 2003 review. The meta-analyses examined the effects of randomized interventions with high or low dietary salt on blood pressure (BP), hormones and lipids. The trials included consisted of subjects with normal or elevated BP, and sodium intake estimated via 24 hour sodium excretion. In total, 167 studies were included that compared dietary sodium intakes <120 mmol with >150 mmol. In studies on subjects with elevated BP, the median trial duration was 28 days,and the average 24 hour sodium excretion in the trials were 71 mmol in the low-salt intake groups and 196 mmol in the high salt groups. In studies on subjects with normal BP, the median trial duration was 7 days, and the average 24 hour sodium excretion in the trials were 50 mmol in the low-salt intake groups and 201 mmol in the high salt groups.

Outcomes were systolic (SBP), diastolic (DSP), and mean BP (MBP), renin, aldosterone, adrenaline, noradrenaline, triglyceride, cholesterol, LDL, and HDL. The results were also analyzed by race.

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Melinda Wenner Moyer, a journalist at Scientific American, recently published a new article titled: It’s Time to End the War on Salt.  I was anxious to read an article with such a dramatic headline (do I need to adjust my perspective?) as Melinda strikes me as progressive and current with articles such as this one that covers recent research suggesting we switch the hard focus off saturated fat and onto refined carbohydrates.  After reading the article and digging deeper, however, I found that most of the article’s references didn’t support the conclusions, and in fact there are some glaring errors that sometimes completely misrepresent scientists and their research.  As with most nutritional issues, there are many ambiguities and disagreements in the literature and you can find evidence to support whatever side you want.  The salt research is especially difficult to navigate, as the debate has been intensively ongoing for decades.  In my opinion, Moyer missed an opportunity to show the public what is still contentious, instead only looking to develop a one-sided piece to downplay the advice we have been told for years she thinks is wrong: to watch how much salt we eat.  This post is not meant to get into extreme detail of the debate but to show what is incorrect about the article.

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