Mice that can’t sense the two tastes find high sodium attractive

By Rachel Ehrenberg

Web edition: February 13, 2013
Print edition: March 23, 2013; Vol.183 #6 (p. 20)

Salt has a split personality with its ability to enhance deliciousness or ruin a dish. Now scientists have revealed the underpinnings of salt’s dark side: Heavy doses of the seasoning trigger taste cells that detect bitter and sour flavors.

Mice without working versions of these taste cells find high levels of saltiness appetizing rather than repugnant, scientists report in the Feb. 14 Nature. The mice even liked a salt concentration equivalent to that of sea water.

The researchers don’t know how high salt levels kick-start the bitter and sour detectors, but the research suggests that a triumvirate of taste cells must oversee salt detection. Dedicated salt detectors enable attraction to salt, while bitter and sour detectors take over when salt levels skyrocket.