Table salt may be able to prevent an infection from spreading, according to a recent study.

Researchers at Vanderbilt University and in Germany have found that sodium -- salt -- accumulates in the skin and tissue in humans and mice to help control infection. They concluded that salt stores may be nature's way of providing a barrier to microbial invasion and boosting immune defenses.

"This is a totally different view on the role of salt in health and disease," Jens Titze, senior author of the study and associate professor of Medicine and of Molecular Physiology and Biophysics, said in a statement.

The study began with the observation that salt levels in mice with infected skin were surprisingly high. Jonathan Jantsch, M.D., a microbiologist at Erlangen and Regensburg Universities in Germany and the paper's first author, suggested that skin might utilize salt accumulation to ward off infections.

Indeed, the researchers found that salt increased the activation of infection-fighting macrophages, a type of white blood cell.

Utilizing a magnetic resonance imaging (MRI) technique they developed, they also found that salt accumulated at the site of bacterial skin infections in six patients.

"The infected legs showed massive salt accumulation, while the uninfected legs were totally normal," Titze said.

The salt accumulation in the infected legs disappeared when the patients were treated with antibiotics.

The researchers also tested the effect of an extremely high-salt diet in mice with persistent footpad infections. Salt stores at the site of the infection increased after consumption of the high-salt diet, and the infections cleared up.

This does not mean that a high salt diet is beneficial for health in the 21st century.

"I think that the most important finding here is that tissues can accumulate massive amounts of sodium locally to boost immune responses where ever needed," Titze said. "This mostly happens totally independent of the diet. This novel biology of salt homeostasis goes beyond the idea that dietary salt is the major component that influences the salt levels in our body."  

With the advent of effective antibiotics and other treatments for infection, humans may no longer need huge salt stores to protect them.

The findings are detailed in the journal Cell Metabolism.