Don't Sweat Your Salt Intake

University of California Davis nutrition researchers are challenging the decades-old conventional wisdom that we should watch our salt.

The controversial article, published this week in the Clinical Journal of the American Society of Nephrology, found that humans naturally regulate their sodium intake, rendering government intervention useless.

It's a study that has angered nutrition policy advocates -- one went so far as to call the study "junk." But co-author David McCarron, an adjunct UC Davis nutrition professor, said it is backed by sound data and he expects such a left-field finding to get heat.

The study concludes that the human body makes sure sodium levels remain within a certain range at all times, similar to bodily functions that are homeostatically maintained, such as body temperature.

"Our sodium intake is regulated by the brain, and your brain won't let you go very far outside of that boundary," McCarron said. "You may eat that whole bag of chips, but it just means that as you sit down you'll unconsciously go toward foods that are lower in sodium."

After aggregating sodium intake data from 20,000 adults in 32 countries, researchers found the adult range of sodium intake to be narrow: between 2,700 to 4,900 milligrams of sodium a day. Because the data encompasses many different dietary cultures, researchers concluded that humans, on their own, maintain a "normal" range of salt intake.

"There looks to be a pretty darn strict lower and upper limit on sodium levels," McCarron said. "Just because our food supply is filled with sodium doesn't mean it's ending up in our bodies."

Furthermore, the authors concludes that the U.S. Food and Drug Administration guidelines are too stringent. Current FDA dietary guidelines recommend no more than 2,300 mg of sodium be consumed per day, which is 14.8 percent lower than the study's observed lower limit.

Co-author Judith Stern, a nutrition professor at UC Davis, said lawmakers should instead focus on more pressing public health issues, such as childhood obesity.