**Summary of the Zinc PCA‑focused article** - **What is Zinc PCA?** A zinc salt of pyrrolidone‑carboxylic acid that combines zinc’s antimicrobial and anti‑inflammatory properties with PCA’s humectant benefits. It helps regulate oil production, keep pores clear, and soothe the skin barrier. - **Why it matters for oily, acne‑prone skin** - Controls excess sebum without harsh drying. - Reduces the growth of *Cutibacterium acnes* (the acne‑causing bacterium). - Dampens inflammatory signals (↓ IL‑1α, IL‑8), leading to less redness and irritation. - **Key scientific findings** - **Sebum regulation:** 0.1 % topical Zinc PCA applied twice daily cut facial sebum excretion by ~30 % after 4 weeks. - **Antimicrobial potency:** MIC against *C. acnes* = 0.5 µg/mL, comparable to zinc pyrithione. - **Inflammation modulation:** In keratinocyte cultures, intracellular zinc rose 2.5‑fold and IL‑1α/IL‑8 secretion fell ~40 %. - **Clinical efficacy:** In a 12‑week, d...