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What causes osteoporosis?

Medically reviewed by Last updated on April 10, 2023.

What causes the bones of people with osteoporosis to become thin and weak?

Official answer


Osteoporosis occurs when our bodies do not make enough new bone or our bodies reabsorb old bone, or both. It is a bone disease characterised by the thinning of bone and loss of bone density often resulting in a bone fracture (broken bone).

Our bones can be weakened in several ways:

  • Calcium is a mineral essential to bone production. We get Calcium through our diet. If we do not get enough calcium in our diet bone production suffers.
  • As we age our body can reabsorb calcium from our bones leaving our bones weak, brittle, fragile and prone to fracture.

This bone loss happens gradually over years and it often is not picked up until a fracture occurs and by then the osteoporosis is well advanced.

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