3. High-Fiber Snack Bars

Yes, everyone needs fiber — it keeps your digestive system churning and keeps you feeling full, even when you're cutting back on calories. What you don't need: Nearly one day's worth of fiber (about 25 grams) in one snack bar, with a diet that's otherwise devoid of it, Harvest says. "Fiber intake has to be consistent throughout the day to stave off hunger, improve digestive health, and not cause stomach upset." So ditch the bars, and try to include some kind of naturally fiber-rich produce — any fruit or veggie will do— in every snack and meal.