What is a Calorie?
A calorie is a unit of energy. It is a measurement of how much energy there is in food we eat. Knowing the calories in our food helps us to balance the energy we eat and the energy we use.
Why are Calories important to humans?
All humans need energy to survive, if we didn't consume energy then our cells would perish. Our vital organs would stop working and we would die.
Calories and Energy Balance
As you eat and drink you're putting energy into your body (Kcal) and the more physical activity you do the more energy you will use up. So to maintain a healthy energy/calorie balance you must even out the calories you consume with the energy you use up. If you consumed the exact number of calories required each day, then you would live a very healthy lifestyle.
Eating too many calories and not using up the energy you've consumed for a sustainable length of time you will start to put on weight. This happens because when you consume too much energy (Kcal) and don’t use all of it then overtime your body starts to store the unused energy as fat.
More Energy IN than OUT overtime = Weight Gain
More Energy OUT than IN overtime = Weight Loss
Your energy balance doesn’t have to be perfect every day it’s how it balances out over time. Children also have to keep an eye on this however they are also growing which should be considered as well.
Estimated Calorie Requirements
|Gender||Age (Years)||Sedentary||Moderately Active||Active|
These levels are based on Estimated Energy Requirements (EER) from the Institute of Medicine Dietary Reference Intakes macronutrients report, 2002, calculated by gender, age, and activity level for reference-sized individuals. "Reference size," as determined by IOM, is based on median height and weight for ages up to age 18 years of age and median height and weight for that height to give a BMI of 21.5 for adult females and 22.5 for adult males.
Sedentary means a lifestyle that includes only the light physical activity associated with typical day-to-day life.
Moderately active means a lifestyle that includes physical activity equivalent to walking about 1.5 to 3 miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life
Active means a lifestyle that includes physical activity equivalent to walking more than 3 miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life.
Checking Calories in your Food
The calorie content is stated on the nutrition label which is usually on the back or the side of the package under the heading of energy. The calorie content is under the letter Kcal (kilocalories) or Kj (kilojoules), kilojoules are a metric measurement of calories.
In many countries such as the EU, Australia and New Zealand they include the calorie content as kilojoules and calories.
1 joule = 0.239005736 of a calorie, or 1 calorie = 4.18 joules.
Examples of Calories used in Sport
- Michael Phelps took in 12000 calories a DAY due to his rigorous training regime he needed the energy he got from foods like eggs, pasta and ham.
- Olympic heavyweight rower when training 3 times a day can consume 6000 calories a day.