I don't have to tell you that a diet won't work if it makes you feel hungry or tired. That's why on the Flat Belly Diet, you're required to eat every 4 hours. Waiting too long to eat can cause you to become so hungry (and irritable) that it's hard to even think clearly. That means you won't have the energy or patience to think through the healthiest meal choice, let alone prepare one. You'll probably want to tear into the first thing you see (bag of chips, handfuls of dry cereal straight from the box, cookies, and so on), and you'll probably have a hard time slowing down while you eat and not reaching for seconds.
Snacks are especially important, but when you eat them is entirely up to you. I like to have a snack in the evening while I'm reading manuscripts, but some of the editors I work with need a small meal in the afternoon to keep them going until dinnertime. Your snacktime is entirely personal and entirely essential. To help you include your snack every day, Cynthia has created a variety of Snack Packs that you can prepare ahead of time and take with you each morning. They're portable and MUFA-loaded. Use the Snack Pack as a floating meal.