I’ve never used this, but it got rave reviews on MUA & one reviewer claimed it helped w/ loss of HCG as one gets older. As far as I know, this wasn’t a claim made (necessarily) by CHANEL so there’s no known scientific validity, but it’s of interest to me because I’m currently researching HCG due to the relationship w/ the pituitary gland & sleep, as well as muscle & bone integrity, circulatory health & youthful skin. In any event, there’s *something* in this that users felt made a difference & it was also said to be soothing/cooling. Not surprising, as ingredients are irrelevant unless the formulation is solid & the PH optimal. CHANEL skincare is pricy in part because they are do a good job w/ the aforementioned; however, for whatever reason, they discontinued this serum.