• A healthy diet for teens means incorporating fruits and vegetables while moderating starch, fat, and sugar.diet image by pershing from Fotolia.com
  
  A teenager's body mass index can be figured by using a BMI calculator on line or at a reputable fitness center. You can also compute it by dividing weight in pounds by height in inches squared, and then multiplying by 705. A teenager's body mass index will help determine if weight is within a healthy range for height and bone structure, and if a better eating plan should be prescribed.
  
  

Balancing a plate

• The U.S. Department of Health and Services states that there is no such thing as a short term diet with lasting effects. While some diets may seem to work at first by eliminating certain foods or eating only specific ones, maintaining such a diet is deprives the body of needed vitamins and minerals. A return to normal eating habits usually results in weight gain. Teens should seek to balance their plate. This means eating a mixture of fruits, vegetables, whole grain, lean meat or legumes, and low-fat dairy products at every meal. This will ensure a long term healthy BMI.
  
  

Serving size

• A healthy diet that leads to a healthy BMI is easily achieved by knowing what counts as serving size. Medium size fruit, like a banana or an orange, equals one serving. If the fruit is chopped, a serving is one cup. Eat one cup of raw vegetables, or half a cup of cooked vegetables. A serving of calcium includes a cup of low-fat yogurt, or one and a half ounces of cheese made with skim milk. Stick to one ounce servings of meat, or one cup of a protein equivalent, such as nuts or soy. In the carbohydrate department, one slice of whole wheat bread counts as a serving, or a cup of something loose such as rice or cracked bulgur wheat.
  
  

Good and bad fats

• When dieting or changing eating habits to reach a healthy BMI, it's important to know that not all fats are bad fats. Fat is a necessary part of the diet, performing important functions like keeping hair, skin, and nails healthy. Good fats are primarily found in plant products, and include peanuts and olive oil. They are also present in some fish, like salmon. Avoid animal based fats like butter, cheese, and fat from non-lean cuts of meat, if you want to improve your BMI.