It's both painful and insulting to rub salt in a wound. But a new study shows that salty skin can actually ward off infections, at least in mice fed a high-sodium diet. That's according to a study in the journal Cell Metabolism. We tend to think of dietary salt as a health threat. And it is. Too much sodium has been linked to high blood pressure and a increased risk for heart attack and stroke. But we also crave salty snacks and store the accumulated sodium in our bodies, particularly in the skin. A clue to explaining this paradox came when researchers noticed that mice that were attacked by a cage mate wound up with an unusually large amount of sodium at the site of the bite. They then found high sodium levels in people at the locations of bacterial skin infections. So the researchers fed mice a high-sodium diet. And found that the dietary salt boosted the activity of immune cells in the animals' skin, which gave them a leg up when it came to healing their wounds.