Proper nutrition means getting all the essential nutrients from your diet that are required to keep your body functioning normally. It is important because there are some important molecules that your body uses to live that it cannot make on its own. The essential nutrients must be obtained in the diet, or your body will have a shortage of them. This is critical because your body needs the right amount of all the required molecules to function properly. It is kind of like a string of holiday lights that needs every light to be in place and functioning properly in order to light up: if just one light is missing, the whole string stays dark. In the same way, if you do not have proper nutrition, your body will lack one or more essential nutrients and will not be able to function normally.