I’m 87 years old. My eye doctor recommended that I use Longenivex products.   I ordered Advantage, and I’ve been using it since September 1, of this year, now for six weeks.  I happen to have white hair above my ears.  I notice that the use of Advantage in that brief period, my white hairs are darkening, as well as my eyebrows. For me, there is no better evidence of the efficaciouness of the use of Longenevix products.  I’ll keep you posted!