Bone Density in Children With IBD Treated With Amorphous Calcium or Commercial Crystalline Calcium

Patients diagnosed with, or in risk of osteoporosis regularly take calcium dietary supplements, although their contribution to BMD maintenance, prevention of bone loss or reduction of the risk of fracture is questionable. Freshwater crayfish rely on amorphous calcium carbonate (ACC), a thermodynamically instable and very rare biomineralized polymorph of calcium carbonate, as the main mineral in the exoskeleton and in their temporary storage organ, the gastrolith. The study hypothesis is that amorphous calcium carbonate (ACC) will have an advantage over calcium carbonate in improving BMD of pediatric IBD patients with reduced BMD. The investigators will include children 10-18 years old with IBD and reduced bone density to recieve regular calcium or amorphic calcium for 12 months with follow up of bone density and confounders as disease activity and medications.