Every RN I have ever met is either fat, or on their way to getting there.  Most I have seen practically run off of fast food and junk food, mainly due to it being easy to grab and go.  Most of the heavy labor and running on the hostipal floors are left up to lower level staff, such as CNAs.  I find it really ironic though.  These people know the consequences of overeating more than anyone through their training, and yet they do it to themselves anyway.