Kim K is Obsessed with waist Trainers

It seems like the newest trendy crase amongst ladies today in the waist trainer…recently made popular by Mrs West. Ladies are now actually wearing corsets all night at any given time, some to even bed, to simply help compress their core, that is designed to eventually shrink their waist and provide them with that hourglass figure (like Kim), but could it be safe to use it constantly and does it really work?