Pass the Salt; Or Not

There has been quite a bit of interest of late in trying to force consumers to ingest less salt as a part of their diet. The problem is that the science is anything but settled on the subject. Studies are inconsistent in showing that reduced sodium intake can occur over the long term and that there are often unintended consequences to public health decisions that were initiated with the best of interests:

Officials responded by advising Americans to shun fat, which became the official villain of the national dietary guidelines during the 1980s and 1990s. The anti-fat campaign definitely made an impact on the marketing of food, but as we gobbled up all the new low-fat products, we kept getting fatter. Eventually, in 2000, the experts revised the dietary guidelines and conceded that their anti-fat advice may have contributed to diabetes and obesity by unintentionally encouraging Americans to eat more calories.

That fiasco hasn’t dampened the reformers’ enthusiasm, to judge from the growing campaign to impose salt restrictions. Pointing to evidence that a salt-restricted diet causes some people’s blood pressure to drop, the reformers extrapolate that tens of thousands of lives would be saved if there were less salt in everybody’s food.

But is it even possible to get the public to permanently reduce salt consumption? Researchers have had a hard enough time getting people to cut back during short-term supervised experiments.

The salt reformers say change is possible if the food industry cuts back on all the hidden salt in its products. They want the United States to emulate Britain, where there has been an intensive campaign to pressure industry as well as consumers to use less salt. As a result, British authorities say, from 2000 to 2008 there was about a 10 percent reduction in daily salt consumption, which was measured by surveys that analyzed the amount of salt excreted in urine collected over 24 hours.

But the British report was challenged in a recent article in The Clinical Journal of the American Society of Nephrology by researchers at the University of California, Davis, and Washington University in St. Louis. The team, led by Dr. David A. McCarron, a nephrologist at Davis, criticized the British authorities for singling out surveys in 2008 and 2000 while ignoring nearly a dozen similar surveys conducted in the past two decades.

When all the surveys in Britain are considered, there has been no consistent downward trend in salt consumption in recent years, said Dr. McCarron, who has been a longtime critic of the salt reformers. (For more on him and his foes, go to nytimes.com/tierneylab.) He said that the most notable feature of the data is how little variation there has been in salt consumption in Britain — and just about everywhere else, too.

As with most food-related issues, I'll take my food in moderation - portion control is the best way to eat healthy, followed by a balanced diet.