Two things. Firstly, It is easy to count 'Points' or 'ProPoints' then it is to count kj's (they are smaller numerals). Secondly, The new ProPoints system doesn't even use kj's - this new system, ProPoints, looks at the composition of the food: it looks at how much Protien, fibre, carbohydates and total fat make up the food; because depending on the food composition our bodies use the food in different ways. Not all calories are created equal - calories (kj's) are simple the 'rate at which food burns', means they set it on fire and time it. Our bodies don't 'burn' food, we digest it, and we do so at different rates depending on what the food is and how it is made up and how our digestive system breaks it down. ie, fibre doesn't breakdown totally but travels through your digestive system, protien takes longer to break down and the energy is released slowly, carbohydrates breakdown much faster, and fats breakdown fastest of all and will then be stores within the body quickest and not sustain you for that long.