What it measures
- Vitamin D
- Calcium
- Phosphate
- Parathyroid hormone (PTH)
- Alkaline phosphatase (ALP)
What does a bone screen test show?
Strong bones need the right balance of calcium and phosphate, controlled by parathyroid hormone and vitamin D. This test checks all of them, plus alkaline phosphatase (ALP), an enzyme that rises when bone is being broken down and rebuilt quickly.
It can reveal problems such as vitamin D deficiency, an overactive parathyroid gland, or calcium levels that are too high or too low.
What it can’t show
A blood test can’t measure how dense your bones are. If you’re worried about osteoporosis, your GP can assess your fracture risk and may refer you for a DEXA scan. This blood test helps find treatable causes of bone loss.
Who it’s for
- Concerns about osteoporosis or a family history of it
- Menopause, or long-term steroid use
- Bone pain or a previous fracture from a minor fall
- Low vitamin D or limited sunlight
How to prepare
- Drink plenty of water beforehand; it makes the sample quicker and easier to take.
- You don’t need to fast.
Bone Screen Blood Test: your questions
Can a blood test diagnose osteoporosis?
No. Osteoporosis is diagnosed with a DEXA bone density scan. A bone screen blood test looks for treatable causes of bone loss, such as low vitamin D or parathyroid problems.
Information on this page is general and doesn’t replace advice from your GP, midwife or consultant. If you feel unwell or are worried about symptoms, contact your GP, call NHS 111 or, in an emergency, 999.