Why does trans-epidermal water loss increase significantly in elderly individuals even when ambient humidity remains stable?

💡 Explanation

Decreased sebum production reduces the lipid barrier on the skin surface, causing higher trans-epidermal water loss, because sebum contains triglycerides, wax esters, and squalene, all of which are crucial for water retention. Therefore, water loss is elevated, rather than a result of altered melanin or collagen.

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