What Is Osteoporosis?

Osteoporosis is a condition in which bones lose density and become porous, fragile, and much more likely to break. The word comes from the Greek for “porous bones” — and that is exactly what happens. Healthy bones are dense and strong; osteoporotic bones, when viewed under a microscope, look like a honeycomb with larger holes than normal.

How Does Bone Density Work?

Bone is not a static material — it is living tissue that is constantly being broken down and rebuilt in a process called remodelling. Specialised cells called osteoclasts break down old bone, while osteoblasts build new bone to replace it.

In younger years, bone formation outpaces breakdown, and bone density increases. Most people reach their peak bone mass around the age of 25–30. After this, bone density gradually declines. In women, this decline accelerates significantly in the years following the menopause, when the protective effect of oestrogen is lost. In some women, up to 20% of bone density can be lost in the first five to ten years after menopause.

Osteoporosis develops when bone is broken down faster than it is replaced, leaving bones increasingly weak and brittle over time.

Why Is It Called “The Silent Disease”?

Osteoporosis has no symptoms in its early stages. There is no pain, no visible changes, and no warning signs — until a bone breaks. This is why it is often called “the silent disease”. Many people only discover they have osteoporosis after they suffer a fracture from a surprisingly minor event, such as a gentle fall, a cough, or lifting a light object.

This is also why bone density testing (a DXA scan) is so important for people with risk factors. It is the only reliable way to detect osteoporosis before a fracture occurs.

Who Is Most at Risk?

Osteoporosis can affect anyone, but it is most common in:

• Post-menopausal women — the most commonly affected group, particularly in the first 10 years after menopause
• Older adults — risk increases significantly after age 60 for women and 65 for men
• People taking long-term corticosteroids (such as prednisolone) for conditions like asthma, rheumatoid arthritis, or IBD
• People with certain medical conditions — including coeliac disease, inflammatory bowel disease, hyperthyroidism, and others
• Men — often overlooked, but one in five men over 50 will have an osteoporosis-related fracture

A full list of risk factors is available on our Risk Factors page.

How Is Osteoporosis Diagnosed?

Osteoporosis is diagnosed using a DXA scan (Dual-energy X-ray Absorptiometry), which measures bone mineral density at the hip and spine. The result is given as a T-score, which compares your bone density to that of a healthy young adult.

A T-score of -2.5 or below indicates osteoporosis. A score between -1.0 and -2.5 indicates osteopenia (lower than normal bone density, but not yet osteoporosis). You can learn more on our Understanding Your Results page.

Can Osteoporosis Be Treated?

Yes. While bone density cannot be fully restored to its youthful level, treatment can significantly slow or halt further bone loss, reduce fracture risk, and in some cases modestly increase bone density. Treatment options include medication (such as bisphosphonates), calcium and Vitamin D supplementation, and lifestyle changes including exercise.

The most important thing is to be diagnosed early. If you think you may be at risk, speak to your GP about a bone density scan.

Frequently Asked Questions