I had shellac for the first time ever last July, for a wedding. Come summer, camping, swimming, gardening etc and the shellac was chipping and growing out. I fully intended on getting it removed properly but didnt get round to it.
Now, I have half a new nail growing through and it looks smoother and flatter by comparison. The shellac bit looks dented and not as smooth as the new nail. So, this led me to think that shellac isn't healthy? I was planning on trying to get a healthy pink shellac and encouraging good nail health but now I'm not so sure.