I consume lots of salt. I eat sour pickles and sauerkraut. I liberally salt my eggs, meat, poultry and fish. I take seriously the derivation of the word “salad” from the Latin “sal” [pronounced sel], which roughly translated means salted raw vegetables, and so wield the salt shaker aggressively over my lettuce, arugula or kale. And for long bike rides in the heat, I power up with a balanced electrolyte solution rich in sodium.
For the record, my blood pressure is 110/70, and I don’t suffer from heart disease, tinnitus, ankle edema, or any of the maladies for which salt reduction is considered de rigeur. Oh, and I’m 63, another reason invoked for salt restriction because it’s said that older individuals’ kidneys can’t eliminate sodium as well.
This, of course, goes against numerous public health recommendations that are parroted endlessly: The World Health Organization recommends that all adults should consume less than 2,000 milligrams of sodium per day, irrespective of whether they have hypertension. The American Heart Association goes even further, urging Americans to limit their sodium intake to below 1500 milligrams per day (the average American consumes more than 3,400 milligrams per day).
New York City, a pioneer in enacting smoking bans (2003) and trans-fat restrictions (2006) under Mayor Michael Bloomberg, has advanced a new rule that would require city chain restaurants to post an ominous icon of a salt shaker encased in a black triangle as a warning next to menu items that exceed 2,300 milligrams of sodium, the upper daily limit called for by the federal government. The rule, challenged in court by the National Restaurant Association, was recently upheld, and violators will be subject to fines of $200. New York City Mayor Bill DeBlasio hailed the court’s decision on what he called a “common sense” regulation in the public interest.
Clearly, there are instances when sodium restriction is merited. Some—but not all—individuals with hypertension respond favorably to sodium restriction. Persons with compromised kidney function lack the ability to filter excess sodium and may experience dangerous swelling. Many Americans with congestive heart failure must restrict their salt intake to prevent fluid overload (It was said—and this may be an apocryphal story—that, in his 80s, the late James Cagney would often ignore his doctors’ advice and indulge in a corned beef sandwich, precipitating trips to the hospital for emergency treatment of acute episodes of congestive heart failure).
But in medicine, things are often not as straightforward as they seem. A surprising degree of controversy surrounds universal recommendations for a low-salt diet. A recent study is only the latest to raise caution flags.
Previous studies had suggested that a very low sodium intake—less than a gram per day—actually has the paradoxical effect of increasing the risk of cardiovascular death. Why might that be?