Osteoporosis
Also known as: brittle bones, low bone density
Medically reviewed by Nano Health Insights Editorial Team · Last reviewed 2026-06-23
Osteoporosis is a bone disease in which bone mineral density falls and fracture risk rises; a DXA T-score of -2.5 or lower defines osteoporosis.
What it is
Osteoporosis is a bone disease in which bone mineral density falls and fracture risk rises; a DXA T-score of -2.5 or lower defines osteoporosis. It develops when bone mass decreases or bone structure becomes weaker, making bones more likely to break, especially at the hip, spine, and wrist. It is often called a "silent" disease because many people have no symptoms until a fracture happens. A low-trauma or "fragility" fracture, such as breaking a bone after a minor fall from standing height, is a major warning sign.
Osteoporosis is more common with aging and after menopause, but it can also affect men and younger people with strong risk factors. Common contributors include low estrogen or testosterone, long-term glucocorticoid use, low body weight, smoking, heavy alcohol use, poor calcium or vitamin D intake, and certain medical conditions that affect hormone balance, the gut, kidneys, or inflammatory pathways. In India, risk may be influenced by lower dietary calcium intake in some groups, vitamin D deficiency despite abundant sunlight, and lower peak bone mass in undernourished populations.
A simple way to think about it is that bone is living tissue that is constantly being broken down and rebuilt. Osteoporosis happens when breakdown outpaces rebuilding for long enough that bone strength drops.
How it works
Bone is remodeled throughout life by two main cell types:
- Osteoclasts break down old bone.
- Osteoblasts build new bone.
In healthy adults, these processes are balanced. With aging, menopause, some illnesses, and some medicines, bone resorption can exceed bone formation. Estrogen loss after menopause is a major driver because estrogen normally helps limit osteoclast activity. In older adults, reduced physical loading, lower calcium absorption, vitamin D deficiency, and falls also add to fracture risk.
Bone strength depends on more than bone density alone. It also depends on bone quality, including microarchitecture, turnover rate, and mineralization. That is why two people with similar bone density can have different fracture risk.
Diagnosis / how it's measured
The main test for diagnosing osteoporosis is dual-energy x-ray absorptiometry (DXA or DEXA), usually done at the hip and spine. It is quick, painless, and uses a low radiation dose.
Key diagnostic terms
| Measure | What it means |
|---|---|
| T-score -1.0 or above | Normal bone density |
| T-score between -1.0 and -2.5 | Low bone mass, often called osteopenia |
| T-score -2.5 or lower | Osteoporosis |
| Fragility fracture of hip or spine | Can support a diagnosis of osteoporosis even without a DXA result |
Doctors also assess fracture risk using age, prior fractures, family history, smoking, alcohol use, body weight, glucocorticoid exposure, and other conditions. Tools such as FRAX may be used to estimate 10-year fracture risk, though thresholds for treatment can vary by country and guideline.
Evaluation often includes looking for secondary causes of bone loss. Depending on the person, tests may include calcium, phosphate, creatinine, alkaline phosphatase, 25-hydroxyvitamin D, thyroid-stimulating hormone, complete blood count, and sometimes parathyroid hormone or tests for celiac disease or multiple myeloma.
Possible clues before diagnosis include:
- Loss of height
- Stooped posture or kyphosis
- Back pain from vertebral compression fracture
- Fracture after a minor fall or minimal trauma
Evidence and uses
The main goal of osteoporosis care is to prevent fractures. Treatment usually combines lifestyle measures, fall prevention, and in higher-risk people, medication.
Lifestyle and prevention
Evidence-based measures include:
- Weight-bearing and muscle-strengthening exercise to help maintain bone and improve balance
- Adequate calcium and vitamin D intake through food and, if needed, supplements
- Stopping smoking
- Limiting alcohol
- Fall prevention, including vision checks, home safety changes, and review of sedating medicines
In India, clinicians may pay particular attention to calcium intake from diet, vitamin D status, and mobility in older adults. Food-based calcium sources can include milk, curd, paneer, ragi, sesame, and some leafy greens, though absorption varies.
Medicines used for osteoporosis
| Drug group | Main role |
|---|---|
| Bisphosphonates | Reduce bone breakdown and lower fracture risk |
| Denosumab | Slows bone resorption; used in higher-risk patients |
| Anabolic agents such as teriparatide | Stimulate new bone formation in selected high-risk patients |
| Romosozumab | Builds bone and reduces resorption in selected patients |
| Selective estrogen receptor modulators or hormone therapy | Used in some postmenopausal women, depending on risks and benefits |
Large clinical guidelines support treatment for people with osteoporosis by DXA, prior hip or vertebral fracture, or high estimated fracture risk. The strongest evidence is for reducing vertebral fractures, with several medicines also lowering hip and other nonvertebral fractures in appropriate patients.
Treatment choice depends on fracture history, age, kidney function, menopausal status, cost, access, and whether fracture risk is very high. Medicines are not interchangeable in all situations, and some require a plan for what happens when they are stopped.
When to see a clinician
See a clinician if you:
- Have a fracture after a minor fall or simple twist
- Notice loss of height, new stooped posture, or unexplained back pain
- Are a woman age 65 or older, or younger with major risk factors
- Are a man with risk factors such as steroid use, low testosterone, prior fracture, or older age
- Take glucocorticoids for weeks to months
- Have conditions linked to bone loss, such as celiac disease, hyperthyroidism, chronic kidney disease, inflammatory disorders, or malabsorption
Urgent assessment is reasonable after sudden severe back pain in an older adult, especially if there is tenderness or recent height loss, because vertebral fractures are often missed.
Limitations and open questions
DXA is useful but does not capture all aspects of bone quality, so fracture risk cannot be judged by bone density alone. Some people fracture with osteopenia rather than osteoporosis-range T-scores, while others with low T-scores may not fracture for years.
There are also practical limits in screening and treatment. Men are underdiagnosed, vertebral fractures are often not recognized, and access to DXA and long-term follow-up can be uneven. Evidence for the best screening intervals and treatment duration varies by drug and risk level.
Long-term therapy raises questions about rare but important harms, such as atypical femur fractures and osteonecrosis of the jaw with antiresorptive drugs, though these are uncommon compared with the fracture risk in untreated high-risk osteoporosis. Stopping some medicines, especially denosumab, can lead to rapid bone loss unless another treatment is started.
Research continues on better risk prediction, how to personalize treatment sequences, and how nutrition, sarcopenia, and falls interact with bone health across different populations. For any suspected osteoporosis or fracture, a clinician can help confirm the diagnosis, look for reversible causes, and choose the safest treatment plan.
FAQs
What is the difference between osteopenia and osteoporosis?
Both terms describe lower-than-normal bone density, but osteoporosis is more severe. On a DXA scan, osteopenia usually means a T-score between -1.0 and -2.5, while osteoporosis means a T-score of -2.5 or lower. Fracture history also matters, because a hip or spine fragility fracture can indicate osteoporosis even if the T-score is not below -2.5.
What are the first signs of osteoporosis?
Often there are no early symptoms, which is why osteoporosis is called a silent disease. The first sign may be a fracture after a minor fall, especially at the wrist, spine, or hip. Some people notice height loss, a stooped posture, or sudden back pain from a vertebral compression fracture.
Who should get tested for osteoporosis?
Testing is commonly recommended for women age 65 and older and for younger postmenopausal women with important risk factors. People with prior fragility fractures, long-term steroid use, low body weight, smoking, heavy alcohol use, or conditions that cause bone loss may also need testing earlier. A DXA scan of the hip and spine is the standard test.
Can osteoporosis be reversed?
Bone loss can often be slowed and fracture risk can be reduced, but complete reversal is not always possible. Exercise, adequate calcium and vitamin D, fall prevention, and medicines such as bisphosphonates or anabolic therapy can improve bone density and lower fracture risk. The best results usually come from early diagnosis and consistent follow-up.
Do men get osteoporosis too?
Yes. Osteoporosis is less common in men than in postmenopausal women, but older men and men with risk factors can still develop it and have serious fractures. Important male risk factors include aging, low testosterone, glucocorticoid use, smoking, alcohol excess, and chronic illness.