Osteoporosis is a condition that affects bone strength. (The word osteoporosis literally means 'porous bones'). Bone tissue is made of tough, elastic fibres (collagen fibres) and gritty, hard material (minerals). It is a living tissue and contains cells that make, mould and take back up (resorb) bone.
This is a companion discussion topic for the original article at https://patient.info/bones-joints-muscles/osteoporosis-leaflet