Bone Density T-Score Interpretation

What Is a T-Score? A T-score compares your bone mineral density (BMD) to the average peak bone density of a healthy young adult of the same sex. The score is expressed in standard deviations (SD) above or below that reference mean.

A T-score of 0 means your bone density matches the young adult average exactly. A T-score of −1.5 means your bone density is 1.5 standard deviations below average.

WHO Classification (T-Score) T ≥ −1.0: Normal bone density T −1.0 to −2.5: Osteopenia (low bone density — not yet osteoporosis) T ≤ −2.5: Osteoporosis T ≤ −2.5 with a fragility fracture: Severe osteoporosis

Where Is BMD Measured? DEXA scans measure bone density at several sites:

• Hip (femoral neck): most clinically important for fracture risk; used as the primary diagnostic site
• Lumbar spine (L1–L4): useful but can be affected by arthritis or prior fractures in older adults
• Distal forearm (wrist): used when hip/spine measurement is unreliable

The lowest T-score across measured sites is used for diagnosis.

Fracture Risk The T-score alone doesn’t fully capture fracture risk — FRAX is the gold-standard tool that incorporates age, sex, BMI, prior fractures, medications, and other factors. Approximate 10-year fracture risk by T-score (simplified):

• T ≥ −1.0: Low risk (<10%)
• T −1.0 to −2.5: Moderate risk (10–20%)
• T ≤ −2.5: High risk (>20%)

Men and Bone Density Men generally have higher bone density than women. The WHO T-score thresholds (based on female reference data) are also applied to men. In older men, a T-score ≤ −2.5 is also classified as osteoporosis.

What Can Improve Bone Density?

• Weight-bearing exercise (walking, jogging, resistance training)
• Adequate calcium intake (1,000–1,200 mg/day for adults)
• Vitamin D supplementation (600–800 IU/day; higher for deficient individuals)
• Medications: bisphosphonates (alendronate, risedronate), denosumab, teriparatide
• Avoiding smoking and excess alcohol
• Fall prevention strategies for those with osteoporosis

Important: T-score interpretation should always be done in the context of a full clinical assessment by a healthcare provider. This tool is for educational purposes only.