How do you Determine the Daily Caloric Requirement for Teens?

Although the average person has a 2,000 calorie diet, which is reflected on the nutrition facts, this number is different for every person. Finding out how many calories you need as a teenager can be difficult, but recognizing the variables makes it easier.

Some variables that affect daily caloric needs are
• gender
• height
• weight
• activity level

There are also methods for calculating you daily caloric needs for both males and females. Here you can see that gender, weight and height all affect how much you should be eating per day.

for males
66+(6.23 x your weight in lb)+(12.7 x your height in inches)-(6.8 x age in years)=basic metabolic rate for a male.

for females
655+(4.35 x weight in lb)+(4.7 x height in cm)-(4.7 x age in years)=basic metabolic rate for a female.

Using your basic metabolic rate you can now find your daily caloric needs based on your activity level using the Harris Benedict equation. This equation involves multiplying your basic metabolic rate by your activity level.

these are the activity levels
BMR(basic metabolic rate)
Sedentary = BMR X 1.2 (little or no exercise, desk job)
Lightly active = BMR X 1.375 (light exercise/sports 1-3 days/wk)
Mod. active = BMR X 1.55 (moderate exercise/sports 3-5 days/wk)
Very active = BMR X 1.725 (hard exercise/sports 6-7 days/wk)
Extr. active = BMR X 1.9 (hard daily exercise/sports & physical job or 2X day training, i.e marathon, contest etc.)

so basic metabolic rate X activity level=daily caloric needs
This equation is pretty accurate and the only variable it does not account for is lean body mass. This makes the equation pretty accurate in everyone except the very muscular and very obese person.

Sources:
http://www.bmi-calculator.net/bmr-calculator/bmr-formula.php
http://healthrecipes.com/calories.htm
http://www.drugs.com/cg/normal-diet-for-adolescents-12-to-18-years-of-age.html