Botox is safe in younger population, the youngest patient I have treated with Botox for cosmetic reasons was 22 years old. If you already started seen lines in the forehead it is a good idea to start using Botox to prevent the progression of the lines. Once the lines becomes static, meaning you can see them at rest , Botox may not be able to provide a full correction. Hope this helps, and remember is never to early to start taking care of yourself:))