A handful of recently published studies suggests that restricting intake may be less beneficial than thepublic thinks and in fact might actually be harmful for some people.
I think I hear a rumbling of approval from the Salt Institute.
The trade group has been working for years to counteract the sodium-is-bad-for-you message so prevalent in the national conversation about health and nutritional standards. The Salt Institute’s latest salvo: a Facebook campaign asking the public to “fight for salt freedom” by leaving online comments for five federal agencies charged with finding strategies to reduce American salt consumption.
The Salt Institute also delivered a 17-page letter in October to the USDA, asking the government to withdraw new federal dietary and school lunch guidelines that call for more restrictions on sodium. The group argues that the sodium provisions are “arbitrary and capricious”, based on “inadequate medical and scientific evidence” and deeply flawed.
Biased much? Of course. The Salt Institute, after all, does represent the industry. At least they’re up front about it; their letter to the USDA is pretty open in pointing out that when salt is unfairly disparaged, it “adversely impact[s] the market for dietary salt, and caus[es] concern for inappropriate regulatory and litigation initiatives.”
But don’t be too quick to dismiss the Salt Institute’s position as one of mercenary self-interest, because it contains a kernel of truth: Humans need a certain amount of salt in their diet, and too little can have health consequences.
The latest study to draw this conclusion appeared a couple of weeks ago in the Journal of the American Medical Association. The study involved an international group of nearly 29,000 adults over age 55 who were at high risk of heart disease and whose salt intake was tracked for three years.
The findings confirmed what medical experts have known all along: Too much sodium led to a significantly greater chance of heart problems. But too little sodium was almost as bad. The individuals in the study who consumed the least salt were more likely to be hospitalized with congestive heart failure or die from a stroke or heart attack.
Other studies have reached similar conclusions about the health risks of reducing sodium too aggressively. For instance, a small-scale study published earlier this year in the journal Metabolism found that low-salt diets may promote insulin resistance and lead to diabetes in some people.
Another study, this one appearing in August in the American Journal of Hypertension, analyzed seven previous studies and concluded that reducing dietary salt did little to lower the risk of premature death.
It’s not clear what to make of all this. In some respects, the debate might be purely academic because for most Americans, the issue isn’t too little salt; it’s too much. New guidelines issued by the federal government this past year call for adults to consume no more than 2,300 milligrams of sodium per day. This daily limit is even lower – 1,500 mg – if you’re older than 51, African-American or have high blood pressure, diabetes or kidney disease.
In view of the fact that the average American adult gets 3,400 mg of sodium per day, much of it from processed foods, there’s obviously room for improvement. But how low can the threshold go? More to the point, how low should it go? Many nutrition experts say that for most people, cutting their sodium intake in half to meet the new dietary guidelines is likely to be very, very difficult and perhaps not achievable for some. And if, as the research suggests, too little salt might be harmful (or at least not all that beneficial), it raises the question of how far we can go before reaching the point of diminishing returns.
I don’t think I’m going to stop buying low-sodium bacon any time soon. It’s still pretty clear that a diet heavy in sodium is undesirable. But it would seem that a little more moderation is called for in the discussion. Perhaps it’s time for a more honest and realistic look at where the bottom limit of sodium consumption should be.
Photo: Wikimedia Commons