Why does hyperkeratosis, resulting in scaly skin, develop in vitamin A deficiency?

💡 Explanation

Vitamin A (retinol) is essential for regulating keratinocyte differentiation. Because vitamin A deficiency impairs the signaling pathways controlling keratin production and maturation, it disrupts the normal shedding and replacement of skin cells. Therefore, abnormal keratin accumulation occurs, leading to hyperkeratosis, rather than melanocyte stimulation, sebum changes, or reduced collagen.

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