Lactic Acid, an alpha-hydroxy acid (AHA) with the chemical formula C3H6O3, functions prominently in skincare as a gentle exfoliant that cleaves corneodesmosomes in the stratum corneum, accelerating desquamation to unveil a refined epidermal layer and mitigate hyperkeratosis. Derived through bacterial fermentation, it exhibits humectant properties by binding water molecules, thereby augmenting the skin’s natural moisturizing factor and reinforcing ceramide synthesis for enhanced barrier integrity against environmental stressors. Clinical trials reveal its capacity to stimulate collagen production, diminishing fine wrinkles and hyperpigmentation via melanocyte inhibition, while its antimicrobial spectrum curbs Propionibacterium acnes proliferation in acne-prone conditions. As an antioxidant, it neutralizes free radicals, fostering even tone and resilience, particularly beneficial for sensitive profiles due to its larger molecular size that limits penetration and irritation. Its inclusion in formulations ensures stable pH, optimizing active delivery for sustained cutaneous health.

In haircare, lactic acid acts as a pH modulator, restoring acidity to the cuticle post-cleansing to compact scales and amplify reflectance for heightened luster and reduced porosity in strands. This organic acid exfoliates the scalp by dissolving sebum and debris, unclogging follicles to alleviate dandruff and promote anagen phase extension for denser growth. As a conditioner, it hydrates the cortex, enhancing elasticity to curtail breakage in chemically processed or environmentally taxed fibers, with studies noting improved tensile strength. Its antimicrobial attributes balance the scalp microbiome, mitigating inflammation and itchiness, while preventing frizz through moisture retention across diverse textures. Commonly, it stabilizes emulsions in treatments, ensuring uniform application for vibrant, manageable locks without residue accumulation.