Actually, snacking can be healthy, as long as you choose wisely.
"It keeps blood sugar stable" and keeps you from getting too hungry between meals, says Debra Waterhouse, RD, author of Outsmarting the Mother-Daughter Food Trap.
"My general rule is going no longer than four hours without eating something, whether a meal or a snack," says dietitian Constance Brown-Riggs, RD.
Update: Try cutting back slightly on meals so you can have one or two daily snacks between 100 and 200 calories. Good choices include nuts, fruit, yogurt, and vegetables with dip.
2. Finish everything on your plate.
"It's fine to leave a little food," Brown-Riggs says. "Get in tune with your body to know when you've had enough."
Update: As you're eating, notice how you're feeling. Are you full? Are you eating just because there is still food on your plate? Be particularly careful when you're eating out -- the food is appealing, the plates are huge, and you may want to eat it all because you paid for it. "If there are large portions, ask for half now and have them box the other half," Brown-Riggs says.
3. Don't eat before exercising -- you'll get a cramp.
You won't want to go running immediately after dinner, but eating a little bit 30 to 60 minutes before exercising can help you maximize your workout.
You'll get "a quick boost of energy that helps you optimize the exercise session," says Natalie Digate Muth, MD, RD, author of "Eat Your Vegetables!" and Other Mistakes Parents Make: Redefining How to Raise Healthy Eaters.
Update: Choose high-carbohydrate, low-fat, low-fiber snacks with moderate amounts of protein in the 100- to 300-calorie range, such as a glass of chocolate milk, a slice of toast with peanut butter, or a granola bar. Fruit is also fine, although it won't have much protein (add a few nuts for that).
4. Hurry up!
Did your parents rush your breakfast so you were on time for school? If you still eat in a hurry, you might miss your body's cues that you're full.
"It takes 20 minutes for the brain to register that you feel full," Brown-Riggs says. "If you eat too quickly, you can scarf down a lot of food in a 20-minute period, and then you feel stuffed."
Update: Slow down. Take mini-breaks by putting your food and utensils down between bites, Brown-Riggs says.
5. You deserve dessert today!
"We never want to use food as a reward; it sends the wrong message," Brown-Riggs says. "The wires get crossed, and we no longer eat because we're hungry; we eat because we were good and we deserve something."
Update: It's great to reward yourself, but not with food. How about a movie, a manicure, or time with friends? "Soon, you'll realize that you shouldn't just eat because you think you deserve something," Brown-Riggs says.