The Centers for Disease Control and Prevention and the American Heart Association need to update the recommended daily sodium intake guidelines, say a group of researchers at the University of Copenhagen Hospital in Denmark. The recommended levels are "excessively and unrealistically low," they say, which can lead to a number of health-related issues. According to their study published in the American Journal of Hypertension, both low- and high-sodium diets are associated with increased mortality.

Fortunately, “around 95% of the global population already consumes within the range we've found to generate the least instances of mortality and cardiovascular disease,” said Dr. Niels Graudal, the study’s lead author.

Graudal says that these findings are important because they help to prove previous findings from an Institute of Medicine 2013 report. The IOM report, which cast doubt on the current CDC recommendations, failed to establish any specific optimum range of intake. "Our results are in line with the IOM's concern that lower levels could produce harm, and they provide a concrete basis for revising the recommended range in the best interest of public health."

The AHA recommends limiting daily sodium intake to no more than 1,500 milligrams — a teaspoon of salt exceeds this amount, as it contains around 2,400 milligrams. The association claims that following these guidelines would decrease high blood pressure by 26 percent. Graudal and his team, however, found that there was little-to-no variation in health outcomes when an individual’s intake remained between 2,645 and 4,945 milligrams per day.

The AHA released a statement Tuesday defending its stance on the matter, saying that no one should change the way they view sodium based on this new study, which, the association says, contains flawed data.

There is a significant body of scientific research that reinforces a very dangerous association between sodium intake and significant health problems, including in some cases death. I wish we could say sodium intake does not matter that much to your health, but it does. Millions of Americans consume too much sodium and as a result face an increased risk for high blood pressure, stroke and other very serious conditions. Based on decades of scientifically sound research, we simply cannot minimize the impact of excess sodium in our diet. [...]

American Heart Association volunteer and staff scientists have found flaws in several of the studies that were used in this newly published research. In fact, we published a Scientific Advisory in February that detailed some of this problematic research that could lead to contradictory findings. In short, this new analysis of these studies should not be used as rationale to reverse public health policy recommendations.

-Nancy Brown, AHA CEO

Graudal still doesn't believe that this information is credible to support the low intake. “The limits recommended by the CDC and AHA are so low, it means the whole population should dramatically change the whole intake. Why recommend something that is not necessary?” he told Medical Daily. He also added that this process of lowering the amount of salt and sodium would be an exorbitant expense for the food industry. However, he did point out that cost is not the main issue.

“The public recommendations are based on assumptions not proven,” Graudal added. “The major parts of the world’s population eats between 2,300 to 4,600. If you decrease the sodium intake to lower it to 2,300, the salt conserving hormones in the body starts to increase — the body is not satisfied.”

He also says that countries where people do not eat fast food but where there is much more salt, as in China and Japan, consume more than 5,000 milligrams of sodium. “My recommendation [would] be to eat as you do," Graudal said. "You should not increase or decrease, unless you already have a problem with sodium intake [higher than 4,600 mgs daily] as that can lead to cardiovascular risks and a higher mortality rate."

Even with this information, the volunteer and staff scientists of the AHA said that, in short, this information [from Graudal] should not "be used as rationale to reverse public health policy recommendations."

Source: Graudal N, Jürgens G, Baslund B, Alderman MH. Compared With Usual Sodium Intake, Low- and Excessive-Sodium Diets Are Associated With Increased Mortality: A Meta-Analysis. American Journal of Hypertension. 2014.