How Does a 1% Increase in Salt Concentration Really Degrade Cellular Function?

Why are our body so sensitive to these tiny changes in osmolality, in the amount of osmolites dissolved in the blood? Why would like a 1% increase in salt concentration really cause that much of a problem? Well, the authors offer some explanations. So if you change your blood osmolability away from its ideal, I would say your body sort of becomes like a city that starts having system-wide problems opening and closing doors. Eventually, this would just cause myriad, diverse problems throughout the city, much like it would in your body.