The more meth you take, the less hungry you'll be. Take moderately large doses and you start not being thirsty too. It can become a serious problem, quite frankly: dehydration isn't unpleasant for no reason -- it's awfully unhealthy.Yeah, the mouthwash will definitely help your teeth not erode. They'll still decay, unfortunately, but apparently it causes a lot of bone and tooth loss if your mouth is dry all the time. I guess our saliva is kind of like a mild acid bath for bacteria that eats our teeth, so it helps kill them. Without it they just feast.