What primarily causes osteoporosis and osteopenia?

Osteoporosis and osteopenia are primarily characterized by a reduction in bone mineral density, which leads to decreased bone strength and an increased risk of fractures. The condition arises when there is an imbalance between bone resorption and bone formation; that is, bones are broken down faster than they are rebuilt. This depletion in bone mineral density affects the structural integrity of the bone, making it fragile and more susceptible to fractures under stress or injury.

While factors such as excessive physical activity or lifestyle habits can influence bone health, they do not directly cause the fundamental changes in bone mineral density that lead to osteoporosis and osteopenia. Similarly, excessive calcium intake is generally not a primary cause of these conditions, as long as calcium levels are within a normal range, the effects are more related to deficiency rather than excess.

Genetic predisposition plays a role in individual risk factors for these conditions but is not the primary cause. Environmental and lifestyle factors combined with the influence of genetics contribute to the overall change in bone mineral density.

In summary, the primary cause of osteoporosis and osteopenia is indeed the depletion of bone mineral density, which is critical for maintaining healthy bone structure.