Over-salting ruins the balance of the immune menu.

Regulatory components of the immune system are critical for preventing unintended activation of immune cells. Failure to prevent this unintended activation raises the risk of developing exaggerated inflammation and autoimmunity. In this issue of the JCI, Binger et al. and Hernandez et al. report that salt can play an important role in undermining regulatory mechanisms of the innate and adaptive immune systems. High salt levels interfere with alternative activation of macrophages (M2), which function in attenuating tissue inflammation and promoting wound healing. High salt also impairs Treg function by inducing IFNγ production in these cells. Together, these results provide evidence that environmental signals in the presence of high dietary salt enhance proinflammatory responses by interfering with both innate and adaptive regulatory mechanisms.