By Shari Levine

Do you want to know a secret?

Losing weight is as easy as doing 1st grade math. Don't believe me? Well, here's the deal: It's a simple equation -- take the number of calories you eat and subtract the number of calories you burn by moving your body. If you eat more calories than your body burns, then over time (like a few weeks or months) you will gain weight. If you burn more calories than you eat for a few weeks, then you will lose weight.

The same equation works for everybody -kids and adults, boys and girls, and animals too. BUT  even though the math is easy, most of us find that losing weight and keeping it off is hard work. It's so hard that some people will try almost any shortcut to make it happen faster.

Because they feel desperate to lose weight, unhealthy fad diets and expensive weight loss products thrive. Companies that sell diet products, such as food or pills, want you to believe that there is a magic way to lose weight, therefore you need to buy something for the trick to work.

Magazine articles and advertisements for diet products also try to trick people into thinking that weight control is easy IF you use their method or product. Your friends may tell you about unhealthy "tricks" to lose weight -- not because they want to hurt you. They think that they're helping you, but don't necessarily know all the facts.

To help you sort out the truth from all of the baloney, here's a list of 5 Big Fat Lies.

Big Fat Lie #1: High protein, low carbohydrate diets are healthy and good for long term weight loss.

Truth be told: It's all the rage "eat only protein and lose weight" so claim the Atkins or South Beach Diet books. You may see people lose weight on this type of diet, but you're only seeing part of the bigger picture. First of all, these diets are almost impossible to keep up because people get bored eating mostly one kind of food. Second, a diet full of protein is unhealthy for your body. You need the vitamins, minerals and fiber that carbohydrates have. And finally, this diet works mainly because people who follow it eat fewer calories not because of a magical food combination. The same is true for all of the funky fad diets that tell you to combine foods in weird ways. These diets only work because people eat fewer calories than normal. (We're back to 1st grade math again.)

Big fat lie #2: Never eat late at night - it will make you gain weight.

Truth be told: The time that you eat is far less important than the total number of calories (remember, this is 1st grade math not magic). Your body doesn't really know what time of day you eat the calories -- it only knows that the calories are energy. So, the best time to eat is when you are active so that you will have the energy you need.

Big Fat Lie #3: You will lose weight if you drink a lot of water.

Truth be told: Your body needs water to stay healthy, but water will not make you lose weight. Some people think that drinking lots of water makes them feel less hungry so they eat less. But water does not have any calories so in the long run it won't replace real food to satisfy your hunger. Remember: this is not a game, and you can't trick your body into thinking it is full of food (energy) when it is not.

Big Fat Lie #4: Skipping meals will make you lose weight.

Truth be told: Some people think that by skipping meals they can eat less calories. Most of the time this diet theory backfires because people who skip meals tend to overeat at the next meal, or later on during the day. It is best to spread your calories out over the whole day so that you will have the energy you need for school and fun.

Big Fat Lie #5: Binging and then purging (throwing up) will help you to lose weight.

Truth be told: Experts studied bulimic girls and measured the number of calories they ate and the number of calories that they purged. Even after they threw up, the girls actually kept about 1500 calories in their bodies. On a regular day, most teen girls eat between 2,000 - 2,500 calories a day. In other words, this strategy is NOT an effective method of weight control and it can lead to dangerous health problems.

The "Secret"

Even though most teenage girls don't need to lose weight because their bodies are still growing, many are fascinated by weight control. If you are truly overweight and need to lose some pounds (and want to keep them off) you should talk with your pediatrician first about what is best for your health. If you, your parents and your pediatrician decide that you need to lose weight, be sure to follow these guidelines:

• Eat a variety of foods that have lots of fiber, vitamins and minerals
• Cut out the high-fat junk foods and sugary drinks that offer little nutritional value
• Turn off the TV and the computer, and increase the amount of exercise you get every day

Remember: your body is an instrument, not an ornament. Take good care of yourself inside and out.