Another study from Varady's group - they've done a fair bit of research on IF in the past. Interesting how the approach is put together: not a compressed eating window, but a 1 day a week fast with the other days being 2 meal replacement shakes and a normal food but calorie controlled dinner. I wonder how important the fast was in this. (the full paper is available)
At least the researchers recognise this - they admit that they do not show whether it was the IF or the calorie restriction that caused the benefits:
This study is limited in that it did not tease apart the effect of IF and CR on body weight and CHD risk. Thus, the independent contributions of the IF diet versus the CR diet on these various parameters, are not known. In order to answer these key questions, a future study should be performed that compares the effect of IF combined with CR, to that of IF alone, and CR alone.