Every time alcohol is consumed, the body is damaged. Usually, the body can repair itself. If the body is overwhelmed, it cannot repair itself and the person will die. Aside from the effect that alcohol has on the body itself, drinking impairs ones judgment. Many of the injuries from drinking underage are caused when people have hurt themselves or others due to lack of co-ordination or poor decision making.
Many people fall when drunk.
They break bones, sprain joints, or knock themselves unconscious. Usually, they recover. Sometimes, a simple fall can end their life. Intoxicated people have fallen down stairs and broken their necks. Or, they have fallen and permanently hurt themselves.