How many kilojoules (kJ) of energy are equivalent to 1 kg of body weight, i.e. without taking in extra nutrition, how many kJ would I need to use to lose 1 kg of body weight?

This answer is brought to you by many of the Australian nutrition professionals who regularly contribute to a nutrition email discussion group.

If you're talking about losing 1 kg of body fat, you need to use 39,000 kJ of energy. If the body weight lost is mostly fat but also some lean body mass (as commonly happens when weight is lost), a little under 30,000 kJ is the amount of energy that needs to be expended. In other words, all other things being equal, if you weigh about 65 kg you need about 2 weeks of jogging 40-50 km per week to lose just one kilogram. No wonder people have trouble losing weight!

For more information Nutrition Australia recommends:

• Weight for a Change

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[Date issued: February 2007]

Disclaimer: This material is provided on the basis that it constitutes advice of a general nature only. It is not intended to replace the advice of a physician or a dietitian.