The Effect of Effervescent Alendronate on Bone Turnover

Inclusion Criteria: * 2 years since last menstrual bleeding * Bone mineral density T-score \< -1 at either lumbar spine or hip * CTx \> 0.42 µg/L Exclusion Criteria: * Ever treatment for osteoporosis * Indication for teriparatide treatment * Treatment with oral systemic glucocorticoids within last 12 months * Rheumatoid arthritis * Inflammatory bowel disease * Untreated thyroid disease * Primary hyperparathyroidism * Diabetes mellitus * eGFR \< 60 mL/min * Cancer within last 2 years except basal cell carcinoma of the skin * Hormone therapy * Unstable liver disease * Contraindications for alendronate * Major gastrointestinal disease within 12 months (eg. esophagitis, ulcer, major surgery). * Vitamin D \< 50nmol/L