HealthTeacher

Understanding Calories

Standard: Identifying energy available from foods
Standard: Relationship between physical activity eating and health

Balancing Food Intake and Physical Activity

What is a Calorie?
Calories are units of energy. Humans need energy to breathe, move, pump blood etc. Our bodies get energy from food. The number of calories in food is a measure of how much potential energy that food possesses.
1 calorie = the amount of energy it takes to raise the temperature of 1 gram of water 1 degree Celsius.

Nutrients that Provide Energy:
Fats, Proteins and Carbohydrates all provide energy to our body and have caloric measurement.

Carbohydrates: 1 gram = 4 calories
Fats: 1 gram = 9 calories
Protein: 1 gram = 4 calories

Energy wise, 1 calorie = 1 calorie no matter what food it comes from. Nutritionally wise, it does matter where our calories come from. Calories from whole grains provide our body with vitamins, minerals and fiber. Calories from sugar don't offer any nutrition.

Monitoring Calories
The number of calories our bodies need to eat is different for every person. This number is determined by calculating the following three factors:

1. Basal Metabolic Rate(BMR): the amount of energy your body needs to function at rest which includes the energy required to keep the heart beating, the lungs breathing, the eyelids blinking and the temperature stabilized.

2. Physical Activity (exercise): The amount of energy we burn when moving our bodies.

3. Thermic Effect of Food: The amount of energy your body uses to digest the food you eat.

Recommended Daily Allowance of Calories
Children, teenage girls, active woman, & sedentary men = 2,000 calories a day.
Teenage boys and active men = 2,000
Sedentary woman and some older adults = 1600

Burning Calories
In order to maintain body weight, the calories we eat need to correlate with the calories we burn. When you burn more than you eat, you will loose weight. When you consume more calories than you burn, you will gain weight. Calories that are not burned are turned into body fat and stored. 3,500 extra calories consumed = 1 pound of body fat. If you burn 3,500 more calories than you eat, your body will convert 1 pound of stored fat into energy.

Calories are burned in the three ways described above: BMR, Physical Activity and Thermic Effect. The metabolic rate that is raised while we exercise continues to function at a higher level for an additional two hours from the time we stop. This results in additional burned calories, hence one of the many benefits of exercise.

The USDA recommends that children and adolescents engage in at least 60 minutes of physical activity everyday in order to maintain average body weight. The USDA also recommends that overweight children increase their physical activity and consume fewer calories while under the care of a physician.

Food	Quantity	Calories
Fast food hamburger double patty	1 sandwich	576
Raisins, seedless	1 cup	434
Chicken, stewed	1 cup	332
Chickpeas	1 cup	286
Chocolate ice cream	½ cup	143
Yogurt plain, whole milk	8-oz container	138
Kiwi	1 medium	46
Popcorn, air popped	1 cup	31
Broccoli, raw	1 cup	30

Source: USDA Nutrient Database found at http://www.nal.usda.gov/fnic/cgi-bin/nut_search.pl

Activity 1-hour	Body Weight	Calories Burned
Backpacking	130 lbs	413
Bicycling 10 mph	130 lbs	236
Cleaning house	130 lbs	207
Bowling	130 lbs	177
Dancing, aerobic	130 lbs	354
Calisthenics, vigorous	130 lbs	472