Ren sirtuin phytohormone replenishing cream is a clean and simple day and night treatment designed for pre and post menopausal skin ren sirtuin phytohormone replenishing cream is a extremely advanced moisturiser designed to prevent and treat the signs of ageing especially those due to hormonal changes by using ren sirtuin phytohormone replenishing cream both day and night skin feels reinvigorated deeply hydrated and looks smoother firmer and brighter naturally