I've used them and never noticed any thing different or any improvement. Though I must admit I was in my late 50's when I started using them and after 2-3 years gave up. I have been on a program though that is causing my gray hair to return to dark. I've been on the Stop Hair Fall Out and restore Hair color modules for 5-6 months. I also take 1 t. of Himalain salt brine each day. It has loads of minerals in it. PS..l I am a woman and my hair was almost totally white and gray except in the back at the base and my crown and sides were very thin. (lots of pink scalp showed) I have lots of new hair now and my hair continues to improve.