What is osteoporosis?

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The word osteoporosis literally means spongy (porous) bone. It causes your bones to become fragile, so they break more easily.

Bone is made up of minerals, mainly calcium salts, bound together by strong collagen fibres. Our bones have a thick, hard outer shell (called the cortex, cortical bone, or sometimes compact bone) which is easily seen on x-rays. Inside this, there’s a softer, spongy mesh of bone (trabecular bone) which has a honeycomb-like structure.

Bone is a living, active tissue that’s constantly renewing itself. Old bone tissue is broken down by cells called osteoclasts and replaced by new bone material produced by cells called osteoblasts.

The balance between the breakdown of old bone and the formation of new bone changes at different stages of our lives.

  • In childhood, new bone is formed very quickly. This allows our bones to grow longer.
  • Later, in our teens and early 20s, the bones stop growing longer but continue to grow in density and strength. Bone density reaches its peak by our mid to late-20s.
  • After this, new bone continues to be produced at about the same rate as older bone is broken down. This means that the adult skeleton is completely renewed over a period of 7–10 years.
  • Eventually, bone starts to be broken down more quickly than it’s replaced, so our bones slowly begin to lose their density. This phase usually starts at about the age of 40 and continues for the rest of our lives.

We all have some degree of bone loss as we get older, but the term osteoporosis is used only when the bones become quite fragile. When bone is affected by osteoporosis, the holes in the honeycomb structure become larger and the overall density is lower, which is why the bone is more likely to fracture.

The effect of osteoporosis on bone

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Osteoporosis identified as potential diabetes complication

Osteoporosis identified as potential diabetes complication

A new study has demonstrated for the first time that diminished bone strength and osteoporosis are potential complications for type 2 diabetes patients.

Research sheds light on fractures among those treated for osteoporosis

Research sheds light on fractures among those treated for osteoporosis

New research has uncovered genetic variations that could explain why some women taking osteoporosis drugs such as bisphosphonates are at risk of atypical fractures in the long bones in their legs.