Why does a Vitamin D deficiency increase fracture risk during falls?

💡 Explanation

Vitamin D is critical for calcium absorption in the intestines. When Vitamin D levels are deficient, calcium absorption decreases, leading to lower blood calcium. Because of this, parathyroid hormone (PTH) increases to pull calcium from bones to maintain blood calcium levels, therefore weakening bone structure, rather than directly impacting collagen synthesis or osteoclast activity.

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