What is the medical term for loss of calcium in bones?

The term that refers to the loss of calcium in bones is osteoporosis. This condition is characterized by a decrease in bone density and quality, leading to an increased risk of fractures. Osteoporosis primarily occurs when the formation of new bone doesn't keep up with the removal of old bone. The loss of calcium is a significant factor in the development of this disease, making bones weaker and more brittle.

Osteopenia is a precursor to osteoporosis and indicates lower than normal bone density, but it does not imply the same extent of loss or the risk of fractures. Osteomalacia refers to the softening of bones due to vitamin D deficiency, affecting the mineralization process rather than directly signifying a loss of calcium. Arthritis pertains to inflammation of the joints and does not directly address bone density or calcium loss. Thus, osteoporosis is the most accurate term associated specifically with calcium loss in the bones.