Sodium restriction may hurt, not help, cardiac patients

While the American Heart Association (AHA) and other prominent public figures (most notably, Mayor Michael Bloomberg) are calling on Americans to restrict their sodium intake, new evidence is suggesting that such recommendations may actually be not only without merit, but harmful.

For instance, a study published last year in JAMA found that, among nearly 30,000 patients with cardiovascular disease or diabetes who were followed for over four years, those who consumed less than 3,000 mg of sodium per day were at a significantly increased risk of cardiovascular events. Considering that the official U.S. dietary guidelines are even more restrictive than this 2,300 mg of sodium per day for the average person, and only 1,500 mg per day for people over 51, African Americans, or those with other cardiovascular risk factors this finding is cause for concern.

And now another study on the adverse effects of sodium restrictions should encourage doctors and public health officials to more carefully review their sodium recommendations. Published in BMJ s Heart, the latest research was a meta-analysis of six studies involving over 2,700 patients with systolic heart failure. After measuring 24-hour urinary sodium levels a good proxy for assessing sodium intake researchers led by a pharmacist in New York found striking results: Compared to those on normal-sodium diets, patients on low-sodium diets had a 95 percent increased risk of death. In addition, low-sodium patients also had a 72 percent higher risk of sudden cardiac death and over double the risk of heart failure. For the study, low-sodium was defined as less than 1,800 mg daily, while normal-sodium diets consisted of 2,800 mg of salt per day.

As ACSH s Dr. Ruth Kava observes, the latest results could be the beginning of a paradigm shift. And in an opinion piece forInternal Medicine News, Dr. Jon O. Ebbert, a professor of medicine and primary care clinician at the Mayo Clinic in Minnesota, hopes the latest findings will generate more discussion among major health organizations. Let s hope they [AHA] can convince us with open minds and thoughtful analysis rather than reflexive defense of traditional paradigms, he writes.