What does it mean when a guy...?

The other day I was I.Ming my friend,I hadn't talked to him for like 3 or 4 weeks and we were talking about T.V shows. Then all of a sudden he said "Btw the girl in my profile picture isn't my girlfriend"...Now I have a habit of over analyzing every little thing someone says to me,so I could be reading into this to far,but why would he tell me this? Could he have been 'just telling me'? Or did he want to change the subject? I mean we were talking about sports! I should have been the one wanting to change the subject.So why do you think he would tell me this?