Photo's. Similar to everyone else on here. Seeing them on people's face book and seeing my face and butt compared to my friends in photos. The big one though, suddenly not having any pants because NONE of the ones you own will zip anymore. That morning of discovery was horrid... and I refused to go shopping for new pants in a bigger size. I just threw on a pair and wore an extra baggy shirt from an ex boyfriend and didn't button them. Embarrassing day. No one noticed, but I felt like the world knew.
I can now fit back into most my jeans...