Calories (also known as kilojoules) are a measure of how much heat is released in our bodies when we convert food energy into our own energy.

1kg of body weight on the scales contains approximately 700g of fat. Each gram of fat is worth 9 calories.

If you want to lose 0.5kg to 1kg of excess body fat each week, you have to reduce your daily calories by 500 to 1000. That is 3500 to 7000 calories over the course of 1 week.

Dieters frequently underestimate how much they eat and overestimate how active they are. The only way to be sure is to keep a record.