If a patient maintains chronically low vitamin D levels while consuming adequate calcium and phosphorus, which consequence becomes most likely regarding bone mineral density?

💡 Explanation

Reduced vitamin D impairs calcium absorption in the intestines, because this triggers increased parathyroid hormone (PTH) secretion, which then stimulates osteoclasts to break down bone and release calcium. Therefore, bone mineral density decreases due to mineral resorption, rather than increased osteoblast activity or sustained calcitonin secretion.

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