L-Ascorbic Acid ek biologically active form hai Vitamin C ka, jo skin pe apply karne se free radicals ko neutralize karta hai, collagen banane mein help karta hai, aur hyperpigmentation kam karta hai. Yeh sabse zyada effective hota hai jab pH low ho, around 3.5 ke aas paas, aur jab formulation stabilized ho.