What Causes Band Of Fat Under Breast After C Section?

It is a month and a half since my c-section, and I healed completely without complications, and have been following my low-fat diet and exercise regiment. However, my water weight is still regulating, and I have increased my bananna consumption. I have noticed that although having to lose my normal pregnancy weight (this was my third child), I have what appears to be a band of fat right under my breasts. Is this fat or possibly water weight as I've read in some blogs?