An elderly patient with decreased sebum production in the skin experiences increased trans-epidermal water loss (TEWL). Which mechanism explains why this sebum deficiency affects the skin barrier function?

💡 Explanation

Reduced sebum production impairs the lipid barrier formation in the stratum corneum, because sebum contains lipids that contribute to the skin's hydrophobic barrier. Therefore, increased TEWL occurs, rather than altered keratinocyte proliferation, melanocyte function, or collagen stability.

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