I sometimes feel dehydrated only on my left side of the body, especially the left side of the face feels dry. Why does this happen?

Driving? If you are more dry on one side of your face, there is most likely a simple explanation. This can happen if you drive a lot and the window is open, or the heating is pointed at that side of your face. Maybe there is something at work that dries you out more on that side. Take your time and figure it out ... The answer will most likely be staring you right on the left side of your face :)!