"The Biologique Recherche Lotion P50 Original 1970 ($101) is a beauty lover's cult favourite that I have used and loved for years. It combines niacinamide, AHAs, and PHAs for an effective, yet gentle exfoliation. I use chemical exfoliants to eliminate dullness and improve my skin texture. It also maintains the proper pH of the skin's acid mantle (pH - 5.5)."