We’ve all seen bent over little old ladies, spines almost folded in two, walking gingerly, slowly, down the street. But how does that happen?
It’s important to remember that bones are a bit like the Golden Gate Bridge: They must be constantly maintained. Your body—like the bridge paint and maintenance crews—is constantly trying to build up your bone, putting down calcium over the protein scaffolding of your skeleton. Meanwhile, bone is constantly being chewed up by the bumps and strains of living, in the same way that wind and water and salt constantly chip away at the famous bridge. It’s a constant process, the wearing away and the building up.