I lost weight on IF before going low carb. I did 19/5 though; I don't think I would have lost much if anything on 16/8. I did do some jogging but not a rigid program.

My IF FaceBook group makes a point of reminding members that they need to find an IF style that works for them; some can lose with 16/8, others do better with one meal a day spread over 4 hours, yet others find success with ADF. And while some can eat what they like in their window, others need to cut their carbs to some extent or radically.