However, a number of actors who’ve drastically changed their bodies for movie roles have detailed their strict regimens — more often than not, with the intention of emphasizing how truly miserable and inadvisable it is.

Before we get into it, let’s first make it very clear that extreme dieting can be incredibly dangerous. The majority of these celebs will have had guidance from a professional while undergoing their transformations, and these regimens are not to be replicated. If you or someone you know needs support, you can find resources here.