Here's What's Shakin' With Salt
David McCarron, MD, a professor of medicine at the Oregon Health Sciences
University, writes that the current recommendations are based on faulty old
studies that vilified salt, not on modern studies and a more sophisticated
understanding of the human body. These old studies don't consider genes that
can make some people more "salt-sensitive" than others. Nor do they
take into account the interaction of other important minerals, such as
potassium, that also affect blood pressure. He also makes reference to some
newer trials that found reducing salt intake doesn't lead to a lower risk of
heart disease deaths, and that it may even increase it.
McCarron argues that by combining the results of these old studies and
analyzing them on a large scale, it becomes apparent that people who have
normal blood pressure reap very little benefit from reducing salt intake.
Additionally, he says, new studies have shown blood pressure is better
regulated by adopting the so-called DASH (Dietary Approaches to Stop
Hypertension) diet, which includes more fruits, vegetables, and dairy products
-- not just by reducing salt. The DASH studies have also suggested that
increased potassium, rather than decreased salt, is much more helpful in blood
"I would never argue that some people, those who have heart, liver,
kidney disease, should watch their sodium intake," says McCarron. But, he
says, "we are burning precious resources in terms of public policy" by
trying to get the general population to reduce sodium intake.
"By definition, public health policy is intended to promote the health
of the public," writes McCarron. Since reducing salt doesn't appear to
benefit most of the population in a significant way, since it may not reduce
heart disease, and since there are other ways of reducing high blood pressure,
the answer to the question 'Should we shake up the dietary guideline for
sodium?' is "Unequivocally, yes."
"The issue about salt has become unnecessarily polarized, and I am not
sure why," Theodore Kotchen, MD, tells WebMD. "I think the more
balanced overview is that salt is one component of a diet that affects blood
pressure -- but it is an important component." Kotchen, a professor and
chairman of the department of medicine at the Medical College of Wisconsin in
Milwaukee, is also a member of the Nutrition Committee of the AHA, which makes
up the recommendations.
"Kaplan's position reflects the thinking of a relatively large number of
professional organizations including the AHA, the National Heart, Lung, and
Blood Institute [part of the National Institutes of Health], and others,"
says Kotchen. "I think it is a balanced and accurate assessment of the salt
"I think McCarron does make some important points, and I think it's true
that we don't have the definitive evidence that perhaps some people would like
before making population-based recommendations, but I do think his conclusions
are somewhat distorted," he says.