When you're surrounded by a wide variety of foods, your appetite will suddenly seem bigger. This isn't a scientific fact, but merely an astute observation. Don't agree? Think about the last time you ate at a buffet. Did you eat more than you usually do?

Now for the scientific facts. According a study published in the journal Eating Behaviors, dieters who were allowed to eat whatever snack they wanted consumed more calories each week than those who were restricted to one type.

Use this logic to your advantage. Whatever it is you crave the most, go for it -- but only it. For example, if your weakness happens to be frozen Snicker bars, avoid having cake, cookies, and Doritos lying around, too. Chances are, you'll soon grow a bit tired of eating the Snicker bars all the time, making you less likely to reach for them when you have an urge to snack. And, because you don't have those other unhealthy treats around, you'll reach for what you do have: healthy snacks.