Did you know that a recent survey stated that two-thirds of girls under 13 have been on a diet?

There is the no-sugar diet and the no-fat diet, the just-eggs diet, the no-carb diet, about a billion liquid diets, the pill-popping fads and the meal-skipping diet. With so many diets and weight-loss plans out there, it’s no wonder so many girls are confused. The problem is, diets like these are not only ineffective in the long-run, they are also extremely dangerous—especially for girls your age. If you want to be healthy now and in the future, keep these tips in mind.

DON'T

Don't Skip Meals: A common mistake that many girls and women make is skipping breakfast, a meal or even a whole day of eating—as part of their “diet.” Nothing could be worse for you and your weight than skipping meals. When you eat breakfast, your body is prepared to burn calories throughout the day. Plus, if you skip breakfast or lunch, you are much more likely to binge on snacks later on, in front of the TV or before bed.

Don't Take Diet Pills: Diet pills may become addictive, and might even create some other serious health problems in real life, too. The fact is: Diet pills can be dangerous. Furthermore, most diet pills, though legal, are not recommended for people under the age of 18. Not only do some of these pills have negative side effects like liver damage, high blood pressure and increased heart rates, they are also especially dangerous for teenagers because there is generally no need to suppress your appetite when your body is still growing. You need a lot of calories to continue growing, and you could stop your bone growth or easily become malnourished if you don't eat enough.

Don't yo-yo: Dieting habits for life start now. Your relationship with food and your dieting technique have the tendency to remain the same throughout your life. So, if you have a habit of dieting hard to lose weight only to gain it all back a month later, you are not setting a good example for your future self. Do you want to be constantly changing back and forth between weights forever? The key is to maintain a healthy weight. If you can only lose weight by extreme dieting, then maybe you are doing something wrong. Or maybe you don't need to lose as much weight as you think you do. Follow our healthy nutrition tips and get at least 30 minutes of exercise three days a week to keep in good shape.

Don't cut out all carbs: With all the hype you've been seeing lately, this advice might be confusing to you. But seriously, you need complex carbohydrates (carbs) in your diet. Remember what you read earlier—you are growing, and the average girl your age needs about 2200 calories per day (although this varies). That means that you are going to have to get some breads and cereals and pastas into your body in order to get through the day. The good old-fashioned food pyramid says you should consume up to six servings of breads, grains and cereals every day. A great tip is to choose whole grains and wheat instead of plain white bread and pasta. The whiter the carb, the less nutrition it has in it (think blah white bread, Twinkies, and boring white spaghetti). Also, you gain lots of great nutrients including iron from these whole-wheat and grain-based complex carbs. Recently, nutritionists warned that strict non-carb dieters may be starving their brains of much-needed glucose, which means that brain functions are impaired and growth is stunted. Also, a lot of low-carb diets focus on high fat intake, which isn't necessarily a good thing. Forgoing bread for bacon is only going to contribute to health problems like clogged arteries, heart conditions and high blood pressure and cholesterol levels later on down the road. Of course, cutting back on carbohydrates by limiting your serving size to one helping of pasta (1 cup = 2 servings!) and only one small bagel (not 3!) is a good way to remain healthy. Replace high-fat low-carb items with nutrient-rich foods like veggies, fruits, lean meats (or non-animal protein sources) and nuts. Talk to your doctor or a registered dietitian if you really want to test out a low-carb diet to find out if it’s a good idea for your body type, and how to do it right.

Don't throw up: Lots of teens think that if they eat too much, they can quickly remedy the guilty full feeling and reduce their calorie count by throwing up. This is a dangerous idea. Purging like this is also very harmful for your throat and mouth because the acids that were present in your stomach are not meant to be in your mouth. Furthermore, if you throw up all of your food, you're not going to get any nutrients. Most of all, puking up snacks sets a very bad example that could lead to some dangerous behavior and a serious eating disorder. If you think you ate too much, suck it up (no pun intended!), keep it in your stomach and take steps to avoid overeating at your next meal. Your stomach takes some time to communicate back to your brain to say “Stop. I’m full.” By eating slowly, taking small bites, chewing your food thoroughly, and paying attention to what you eat while you eat it (that means focusing on your food when you eat, not watching TV or IMing with your friends during dinner or snacks) you’ll give your stomach enough time to signal your brain. That means you’ll have a better chance of stopping before you’ve eaten too much and need to put on those extra baggy pants to feel comfortable.

Don't obsess about food: If you’re on a diet that’s running your life, then you’re not on the right diet. If you set unrealistic goals for yourself and then become preoccupied with attaining them, you are going to have major problems. Your aim shouldn't be to get to an "ideal weight" or into a tiny pair of jeans. So, if you are dieting so you can look like Britney or Jessica Simpson, then you are not dieting for the right reasons. The only reason that a girl at your age should even be going on a diet is if she is severely overweight or obese. Click here for more info on teen obesity. In fact, most nutritionists say that dieting before you are 20 is a major no-no. Instead, set realistic and reachable goals. For example, tell yourself that you want to start feeling better, or eat the right amount of vegetables, or run in a mini-marathon. Then eat in order to help yourself achieve those goals. Check out our How to Eat Right section for advice on how to get there, and don't forget to exercise!