The human skeleton is pretty tough. If you drink a lot of milk and get plenty of sunshine, your bones can grow to be stronger than concrete* By weight, anyway. A pound of bone is stronger than a pound of concrete, but only just.; shattering a bone requires a really, really strong hit, as in "crashing your car at 60 km/h"-strong. Did you know that crematoria actually grind bones because otherwise [...] [tvtropes.org]