Are Prepared Foods Making Us Fat?

Having slowly switched to a (nearly) completely DIY diet over the past six years, I've lost about 25 or 30 pounds, though I have a small frame (5'10") and was never particularly heavy to begin with (170lb or so down to 145lb). Food you make yourself certainly tastes better---most prepared food I've tried has been full of rancid oils and musty, stale flavors.

Nevertheless, I'm hesitant to blame prepared foods as a genre. I think the real problem is a lack of consciousness, where people habitually overeat rich foods. Some of my coworkers have sizable portions of meat and cheese at nearly every meal---I don't know how they do it!