Sensible, Sustainable Energy Targets
Weight change depends on energy balance over weeks and months, not on any single meal. These guides help you estimate your maintenance kilojoules, choose a realistic deficit, and track accurately whether your labels are in kJ or Calories.
We focus on approaches that are safe for healthy adults: moderate deficits of about 1,000-2,100 kJ (250-500 Calories) a day, enough protein and fibre, and regular check-ins rather than crash diets.
Tools That Help
- Daily kJ calculator, maintenance and weight-loss targets.
- Macros to kJ calculator, check the energy in a meal.
- Food kJ chart, find lower-kJ swaps.
These articles are general information. If you are pregnant, breastfeeding, under 18 or managing a medical condition, please speak with a doctor or accredited dietitian before changing how much you eat.
What Realistic Progress Looks Like
A deficit of about 2,100 kJ a day is often quoted as losing roughly half a kilogram a week, because a kilogram of body fat stores around 32,200 kJ. Real progress is rarely that tidy: early weeks include water changes, and your energy needs fall as your weight drops. Looking at a weekly average of your weight, rather than single weigh-ins, gives a much clearer picture.
Small, repeatable changes usually beat drastic ones, swapping sugary drinks for water, choosing smaller coffee sizes, filling half the plate with vegetables and walking more each day can add up to a meaningful kilojoule difference without feeling like a diet.