Diabetes increases fracture risk through two different patterns. Type 1 diabetes lowers bone mineral density and raises hip fracture risk roughly 6-fold. Type 2 diabetes often shows normal or higher density on DXA but still carries about 2× the hip fracture risk — driven by poor bone quality from advanced glycation end products, microarchitectural defects, and a higher fall rate from neuropathy and hypoglycemia. Thiazolidinediones (pioglitazone, rosiglitazone) and the SGLT2 inhibitor canagliflozin add to risk. Prevention combines bone-targeted strategies (calcium, vitamin D, weight-bearing exercise, possibly bisphosphonates) with fall risk reduction.
The Type 1 vs Type 2 Bone Paradox
Type 1 Diabetes
- Lower bone mineral density at hip, spine, and wrist
- Onset of disease in childhood and adolescence may impair peak bone mass
- About 6× the hip fracture risk of non-diabetic peers
- About 2× wrist and vertebral fracture risk
- Mechanisms: insulin deficiency (insulin has anabolic effect on bone), IGF-1 alterations, low bone turnover
Type 2 Diabetes
- Bone mineral density usually normal or higher than peers
- Still about 2× hip fracture risk despite normal DXA
- DXA underestimates fracture risk in T2D — clinicians may use a “diabetes correction” with FRAX
- Mechanisms: advanced glycation end products (AGEs) cross-link bone collagen and weaken matrix, cortical porosity, low bone turnover, increased fall risk from neuropathy and hypoglycemia
Why Falls Matter as Much as Bone Density
- Diabetic peripheral neuropathy impairs proprioception and balance
- Visual loss from diabetic retinopathy reduces obstacle detection
- Severe hypoglycemia can cause sudden falls — particularly insulin or sulfonylurea users
- Orthostatic hypotension from autonomic neuropathy
- Sarcopenia (muscle loss) common in long-standing diabetes
- Polypharmacy — multiple medications increase confusion and dizziness
Diabetes Medications and Fracture Risk
| Drug Class | Bone Effect |
|---|---|
| Thiazolidinediones (pioglitazone, rosiglitazone) | Clear increase in fracture risk, especially in postmenopausal women |
| SGLT2 inhibitors | Canagliflozin had fracture signal in CANVAS; empagliflozin and dapagliflozin do not |
| Insulin | Neutral on bone; severe hypoglycemia increases falls |
| Metformin | Neutral, possibly mildly bone-protective |
| GLP-1 receptor agonists | Neutral on bone in trials |
| DPP-4 inhibitors | Neutral |
| Sulfonylureas | Neutral on bone; hypoglycemia risk increases falls |
Screening — DXA and FRAX
DXA Scan
- Dual-energy X-ray absorptiometry measures bone mineral density at hip and spine
- T-score compares with young adult average: -1.0 to -2.5 is osteopenia, ≤-2.5 is osteoporosis
- Z-score compares with age-matched peers (used in younger patients)
- Recommended for women 65+, men 70+, and earlier with risk factors
FRAX (Fracture Risk Assessment Tool)
- Calculates 10-year probability of major osteoporotic and hip fracture
- Combines age, sex, weight, height, prior fracture, parental hip fracture, smoking, alcohol, steroid use, rheumatoid arthritis, secondary osteoporosis
- Does not formally include diabetes but underestimates risk in T2D
- Some clinicians add a 10-year age correction for diabetes
- Treatment threshold: 10-year hip fracture risk ≥3 percent or major osteoporotic ≥20 percent
Calcium and Vitamin D
- Calcium target: 1000 mg daily for women under 50 and men under 70, 1200 mg for older adults
- Food sources preferred (dairy, leafy greens, fortified foods, canned salmon or sardines)
- Supplement only the gap if dietary intake is insufficient — high-dose supplements may have small cardiovascular signal
- Vitamin D target: serum 25(OH)D ≥30 ng/mL (some labs use ≥20)
- Supplement 800 to 1000 IU daily for general adult bone health; higher doses if deficient (e.g., 50,000 IU weekly for 8 weeks per clinician)
- Vitamin D deficiency is common in people with diabetes due to obesity (vitamin D sequestration in fat) and indoor lifestyle
Bone-Targeted Drugs
| Drug | Class | Route and Frequency |
|---|---|---|
| Alendronate (Fosamax) | Bisphosphonate | Oral weekly |
| Risedronate (Actonel) | Bisphosphonate | Oral weekly or monthly |
| Ibandronate (Boniva) | Bisphosphonate | Oral monthly or IV quarterly |
| Zoledronic acid (Reclast) | Bisphosphonate | IV annually |
| Denosumab (Prolia) | RANKL inhibitor | Subcutaneous every 6 months |
| Teriparatide (Forteo) | PTH analog (anabolic) | Daily subcutaneous injection |
| Abaloparatide (Tymlos) | PTHrP analog (anabolic) | Daily subcutaneous injection |
| Romosozumab (Evenity) | Sclerostin inhibitor (anabolic) | Monthly subcutaneous for 12 months |
| Raloxifene (Evista) | SERM | Oral daily |
Exercise for Bone and Fall Prevention
- Weight-bearing aerobic activity 3 to 5 times weekly (brisk walking, hiking, dancing, tennis)
- Resistance training 2 to 3 times weekly (free weights, bands, body weight)
- Balance training: tai chi, single-leg stands, heel-to-toe walking
- Yoga and Pilates for posture and core strength
- Avoid forward flexion-only exercises (deep crunches, toe-touches) if vertebral fragility is present
- Pool exercise builds muscle but is less effective for bone density
Home and Lifestyle Fall Prevention
- Remove loose rugs and clutter from walking paths
- Add grab bars in bathroom, especially shower and beside toilet
- Improve lighting, especially night-lights along hallway and bedroom
- Wear well-fitting closed-toe shoes inside and out; avoid loose slippers and bare feet
- Use a cane or walker if balance is impaired
- Address vision: annual eye exam, current prescription, cataract surgery when indicated
- Review medications with clinician to minimize sedatives, sleep aids, and unnecessary antihypertensives
- Hearing aids — falls are more common with untreated hearing loss
- Pet safety (small pets underfoot cause many falls)
Hypoglycemia and Fractures
- Severe hypoglycemia can cause sudden falls with significant injuries
- Higher-risk medications: insulin, sulfonylureas (glipizide, glyburide, glimepiride), meglitinides
- Discuss medication choice with clinician — GLP-1 RA, SGLT2 inhibitors, DPP-4 inhibitors do not cause hypoglycemia alone
- Continuous glucose monitor (CGM) reduces unrecognized hypoglycemia
- Glucagon kit available for emergencies (nasal Baqsimi, prefilled Gvoke)
Other Bone Risk Factors to Address
- Smoking — independent risk factor for low bone density and fracture
- Excess alcohol (more than 2 drinks daily for men, 1 for women)
- Vitamin B12 deficiency, common in metformin users — consider checking annually after 5 years on metformin
- Hypogonadism (low testosterone in men, premature menopause in women)
- Thyroid disease — both hyperthyroidism and over-replaced hypothyroidism harm bone
- Chronic kidney disease — alters calcium, phosphorus, vitamin D, and PTH
- Long-term steroid use (prednisone ≥5 mg daily for ≥3 months)
- Eating disorders and very low body weight
Special Considerations
Postmenopausal Women with Diabetes
- Highest fracture-risk population
- DXA at age 65 or earlier with risk factors
- Consider hormone replacement therapy benefits and risks individually
- Anti-resorptive or anabolic therapy if T-score ≤-2.5 or prior fragility fracture
Men with Diabetes and Low Testosterone
- Low testosterone is common in T2D and impairs bone density
- Testosterone replacement, when clinically indicated, improves bone density
- DXA appropriate at age 70 or earlier with risk factors
Older Adults with Cognitive Impairment
- Fall risk is particularly high
- Adherence to oral bisphosphonates is poor — annual IV zoledronic acid or 6-monthly denosumab may be preferred
- Caregiver education on home safety
Related Reading
See our overviews on complications and related conditions and treatment options. The Bone Health and Osteoporosis Foundation publishes practical screening and treatment guidance.
The Bottom Line
Diabetes increases fracture risk in both type 1 and type 2 forms, but through different patterns. Type 1 lowers bone density and raises hip fracture risk about 6×; type 2 often shows normal density but still carries 2× hip fracture risk due to poor bone quality and a higher fall rate from neuropathy and hypoglycemia. Thiazolidinediones and canagliflozin add to risk; metformin, GLP-1 receptor agonists, and most SGLT2 inhibitors do not. Screening with DXA is reasonable at age 65 in women, 70 in men, or earlier with risk factors. Prevention combines calcium and vitamin D, weight-bearing and resistance exercise, fall prevention in the home, and bone-targeted drugs (bisphosphonates, denosumab, anabolic agents) when indicated. Talk to your doctor about a personalized bone health plan.
