Britney Spears -- My Women's Health Cover is the Real Deal ... Here's Proof!

Britney Spears looks ... different on the cover of Women's Health Magazine, and while many people suspect a Photoshop job -- TMZ has obtained video that shows that's probably not the case.

Sources involved with the photoshoot tell TMZ ... Britney's facial changes can be attributed to a makeup technique called "contouring" ... which accounts for her slimmer nose and more defined cheek bones.

Check out the video ... she looks exactly the same on set as she does in print.

It really is Britney, bitch.