Balancing energy in and out
What are kilojoules (kj) or calories?
Energy is measured in kilojoules (kj) or calories, so when we refer to ‘energy in’ we actually mean ‘kilojoules in’ (the kilojoules in the food we have eaten).
Maintaining a healthy weight range is important for minimising the risk of many lifestyle diseases such as heart disease, some cancers and type 2 diabetes.
The best way to maintain a healthy weight is to match the energy you consume from food with the energy that your body uses up.
Energy in = Energy out
The table below is a guide to the estimated daily energy requirements for an ‘average’ person with low level of physical activity, eg sedentary work such as office work, and no strenuous exercise.
Actual energy needs for individuals will vary considerably depending on activity levels, body composition, state of health, age, weight and height.
Estimated daily energy requirement (kilojoules) for a sedentary person
(eg office work or study, no strenuous physical activity)
|Adults over 70 years||8300*||7200^|
Source: National Health and Medical Research Council, .
* estimated energy intake for male 180cm tall, 71.3kg
^ estimated energy intake for female 170cm tall, 63.6kg
The amount of energy delivered by the nutrients in food is as follows:
- Carbohydrates – 16.7 kj per gram
- Protein – 16.7 kj per gram
- Fat – 37.7 kj per gram
- Alcohol – 29.3 kj per gram
Source: National Health and Medical Research Council.
These figures represent the average amount of energy released from these nutrients