Cutting back on salt is smart and safe, no matter what the New York Times says. In an editorial and an article, the Times misrepresented the findings of a new report from the Institute of Medicine (IOM). Here's what the Times got wrong:
The Times never told readers that the IOM found insufficient evidence that very-low-sodium diets are risky. The editorial cites "emerging evidence" and the article cites "troubling" findings that diets low in sodium (mostly from salt) are harmful. However, the Times failed to tell readers that, according to the IOM, the evidence of harm from low-sodium diets is "insufficient and inconsistent."
The problem: The IOM found serious methodological flaws in all of the studies suggesting harm from low-sodium intakes. And some of those studies involved a bizarre treatment for congestive heart failure that isn't used in the United States. (The treatment severely limits not just salt, but how much water people can drink.)
The Times article described studies done before 2005 as flawed, but it describes the recent studies that "found adverse effects on the lower end of the sodium scale" as "more careful and rigorous." How could the Times confuse "insufficient and inconsistent" with "more careful and rigorous"?
The Times failed to inform readers that few Americans consume very-low-sodium diets.
The Times not only fanned unfounded fears that cutting sodium is risky, but it failed to inform readers that vanishingly few Americans consume the very-low-sodium levels that the IOM considered. More than 97 percent of adults up to age 50 -- and more than 95 percent of adults over 50 -- consume more than 1,500 milligrams of sodium a day. And 75 percent of women and 96 percent of men consume more than 2,300 mg a day. (And those percentages are underestimates because they're from surveys that ask people what they recall eating and don't include salt from the salt shaker.) Of course, most people who are trying to eat less salt have no idea whether they are consuming 2,300 mg or 1,500 mg or less per day. The Times may lead many to assume (erroneously) that they have cut their sodium intake enough to "suffer adverse health effects."
The Times imperiled its readers' health by implying that all advice to cut salt is wrong.
"The panel did not conclude that the average intake of 3,400 milligrams a day is necessarily risky," said the Times editorial. Of course, it didn't. The IOM wasn't asked to examine the risks and benefits of our current sodium intakes. Previous IOM committees concluded that they are harmful. The IOM was asked to look at the effects of intakes in the 1,500 mg to 2,300 mg range.
"After years of warnings to cut sodium consumption to reduce heart attacks and strokes, it is disturbing to learn how little evidence exists that such reductions would actually be beneficial to health," opined the editorial. These and other statements imply that Americans should ignore all previous advice from health authorities to cut salt.
Ironically, the editorial concluded by stating that the new report "called for more vigorous research to clarify an issue that is sure to be confusing for the public." Clearly, the Times did its part to add to that confusion. While the IOM report should have been written more clearly, the nation's leading newspaper bungled the story. Most other major media -- including Reuters, the Associated Press, USA Today, and National Public Radio -- got it right.
All the key major health authorities -- including the American Heart Association, National Institutes of Health, and the World Health Organization -- have urged the public to cut back on salt to combat the global epidemic of elevated blood pressure, a major cause of heart attacks, strokes, congestive heart failure, and kidney disease. Worldwide, elevated blood pressure causes more preventable deaths than tobacco, obesity, alcohol, or any other cause, according to the World Health Organization. Two out of three U.S. adults have either hypertension or prehypertension. It's an epidemic. And eating too much salt raises blood pressure. That's the true public health problem.
The IOM ignored the mountain of conclusive evidence that cutting sodium reduces blood pressure, a missing "critical component" that led the American Heart Association to stand by its recommendation "that all Americans eat no more than 1,500 mg a day of sodium." What's more, we have evidence that cutting sodium from current levels lowers the risk of heart attacks and strokes in people with prehypertension (that's about one in three adults). A follow-up of the Trials of Hypertension Prevention was among the very few studies that had no flaws, according to the IOM. The follow-up found 25 to 30 percent fewer heart attacks, strokes, and other cardiovascular events in people who cut their sodium by 25 to 35 percent (from 3,556 mg a day down to 2,286 mg a day in one part of the study and from 4,207 mg down to about 3,229 mg in the second part).
Why didn't the IOM find evidence of benefit in people who ate less than 2,300 mg of sodium a day? The fact is that no good studies have been done. Studies can't test whether a diet with, say, 1,500 or 2,000 mg of sodium a day lowers the risk of heart attacks and strokes, because such a study would have to keep hundreds or thousands of people on a very-low-sodium diet for years. Eating so little sodium is just not practical as long as the food industry keeps dumping so much salt into our foods.
Just gradually reducing our sodium intake to 2,300 milligrams a day, about a 40 percent reduction for most people, would yield enormous benefits. Doing so would save an estimated 280,000 to 500,000 lives, as well as about $90 billion in medical costs over the next decade. Inasmuch as the food industry is not lowering sodium levels enough on its own, it's high time that the Food and Drug Administration did what a landmark 2010 IOM report recommended: set limits on sodium for different categories of food.
But you don't have to wait for government action to protect your health. Instead, read food labels carefully, eat smaller portions at restaurants (where sodium levels are notoriously high), and choose more fruits and vegetables, which are naturally low in sodium and high in potassium, which helps lower blood pressure.
For more by Michael F. Jacobson, click here.
For more health news, click here.