I'm 20 and I've noticed recently that my areolas have lightened/are fading around the edges. Is this normal?

I noticed this change within the past month but I believe compared to about a year ago my areolas are significantly lighter. I'm not pregnant, never have been nor am I sexually active (in any way). Some other details, I was told at 17 that I had a cyst in my ovaries but it was related to my high weight. Within the past eight months though I have lost over 50lbs and while my breasts have gotten smaller, my areola/nipple size and color remained the same.