Why does vitamin D deficiency increase the risk of osteoporosis?

💡 Explanation

Vitamin D is crucial for calcium absorption in the intestines; impaired absorption leads to lower blood calcium levels. This stimulates parathyroid hormone release, causing calcium to be leached from bones via increased osteoclast activity, because this process aims to maintain blood calcium homeostasis. Therefore, weakened bones result, rather than direct impacts on collagen or phosphate.

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