Besides thinking of how long you can live, if you haven't been eating for a while your body loses a lot of nutrients which are vital to your survival and overal well-being. Even if you began to eat again after say 10-11 days your body is still is sorry shape and it will take a couple of days before your back to normal. I highly suggest you invest in some kind of vitamin supplement to atleast keep some kind of nourishment in your system.