HIE EVR1,brIn the last 1 month since I got smoothening done, I haven't noticed any ill effects on my hair and health. The hair looks perfect, and I haven't noticed any side effects that could have occurred, Like dry scalp,Thinning of hair etc.., AND THE RESULT WAS GREAT,Anybody who has frizzy hair. Wavy and slightly curly hair will love this treatmentbr! LOVE MY NEW LOOK! THANK YOU GUYS!!!thanks to Ksaloonbr