Anti-aging claims for “reactivating cell regeneration” are under scrutiny by the U.S. Food and Drug Administration (FDA), but still appear on many products including Shu Uemura’s Tsuya Youthful Radiance Generator Essence. This column will review the ingredient listing for claims and functionality.
This serum contains several humectants including sugar derivative rhamnose, butylene glycol, glycerin and methyl gluceth-10. There are also a number of silicone derivatives including bis-PEG-18 methyl ether dimethyl silane, dimethicone and dimethiconol/methylsilanol/silicate crosspolymer, which provide slip, conditioning and emolliency.
More than likely, any ingredient appearing in the list after methyl gluceth-10 is present in the formula at 1% or less. Hydroxyethylpiperazine ethane sulfonic acid is classified as a buffering agent for maintaining enzymatic structure, but is formulated into many products for pigment regulation and skin brightening to support the “translucent” claim.
The thickening/stabilizing agents are carbomer and acrylates/C10-30 alkyl acrylates crosspolymer, which is neutralized with pH adjustor potassium hydroxide. Hydrogenated lecithin and surfactant decyl glucoside are probably included as co-emulsifiers.
The cosmeceutical or “bio-active” ingredient is Salix alba bark (willowbark) extract, a natural source of salicylic acid that helps exfoliate the skin. The preservative used is ethylhexylglycerin, which is boosted by chelating agent disodium EDTA. Ethylhexylglycerin is not considered broad spectrum when used alone, and it is usually combined with other preservatives. Mica, titanium dioxide (CI 77891) and red 4 (CI 14700) add a little tint and opacity to the serum.