One of the bonuses about the intermittent fasting lifestyle is that no food is off limits. While you can eat high-carb foods like pasta, pizza, bread, and fruit smoothies, you want to make sure that you're eating enough protein to prevent hunger. If you don't, you'll end up feeling hungry, which can result in you eating more.
Leslie Langevin says, "The basic idea is that IF is a tool, but if you're not paying attention to calorie intake, or a balanced intake during your eating window, that can backfire," and result in weight gain.