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So, you know you should only be eating a certain number of kilojoules or calories each day, but how do you find out how many you should be eating? And what does that actually look like?

How many kilojoules should I be eating?

First of all, it’s important to understand what a kilojoule is. A kilojoule is a measure of the energy in food and drink, which is something we all need to keep our bodies functioning. Click here to learn more about kilojoules, and the difference between kilojoules and calories. Watch the below video to find out how your body gets kilojoules from the food you eat.

The number of kilojoules you should be eating is going to depend on your gender, age, weight and the amount you exercise. Use our kilojoule calculator to help you figure out how many kilojoules to eat each day.

A general figure that’s often referred to is 8,700 kilojoules, which is regarded as the average daily intake of an Australian adult. This number is just a rough guideline though, as the number of kilojoules different people use every day can vary quite a lot depending on how active they are.

Kilojoules are often spoken about in connection to weight gain and loss. Generally speaking, if a person eats more kilojoules than their body burns, their body will store the excess as fat. If a person eats fewer kilojoules than they need, their body will use stored fat to meet their requirements.

So, what does a daily intake of kilojoules look like as food and drink?

We put together some examples of daily diets for different Queenslanders to show you how kilojoules add up. The numbers we’ve used are just averages: the actual number of kilojoules in a food will depend on the type of food and brand, preparation methods and amount eaten.

Remember: a food’s kilojoule count doesn’t indicate its nutritional value. It is possible to eat your daily kilojoule requirement by consuming unhealthy food, but you will only get the nutrients you require from eating a good balance of different types of food.

For example, the average adult man could eat between 12 and 15 chocolate bars (36g) to fulfil his kilojoule (or energy) needs each day, but this diet would severely lack a lot of the nutrients necessary to maintain a healthy body!

Sample diet: Queensland Woman

Meet Queensland Woman, we’ll call her QW for short. She is lightly active, taking a short walk every morning, and sits down most of the day when at work. Her daily energy requirement is 8,970kilojoules.

For this day, QW’s diet is higher than her kilojoule requirement. If her body doesn’t burn the excess kilojoules she’s consumed, it will begin to store it as fat. To counter this, she could do more exercise, or change some of the foods that she is eating which are high in kilojoules.

What about the sweet treats for between meal snacks? You can see that QW has consumed more kilojoules from the vanilla slice at morning tea than at lunchtime with this treat.

Discretionary foods, or foods that are high in sugar, fat or salt, are often much higher in kilojoules than we might guess. To maintain a healthy diet, it’s important to be aware of what is in the food we are eating, and eat discretionary foods only occasionally.

QW might have her vanilla slice and chocolate biscuits on a special occasion, but choose to have a healthier snack like some fruit on regular days instead to lower the total daily kilojoule intake.

Sample diet: Queensland Man

Our next example, Queensland Man (QM), works at a job that requires lots of physical activity throughout the day, so his current daily energy requirement is quite high at 14,350kilojoules.

QM is over his kilojoule count for the day, which is bad news because he’s trying to lose a bit of weight.

Drinks are building up his kilojoule count, and some don’t even add a lot of nutritional value to his diet. It’s easy to forget that there are kilojoules in drinks as well as food, and sugary drinks and alcohol can contain a surprising amount.

Knowing how high in kilojoules they are, QM might think about his drink choices as a first step to lowering his kilojoule intake. It’s important he still gets enough fluids to stay hydrated, so most of the time he should choose to drink water instead. He could also skip the fries with his lunch and try some healthier snacks between meals.

How can I apply this information to my life?

A healthy diet isn’t just about kilojoules, but understanding what kilojoules are and how your body uses them is a really good start. Once you know how many kilojoules your body requires in a day and what types of food to aim for, it’s time to create a meal plan.

Like our examples above, mapping out your diet in advance can help you check that you’re going to meet your goals. You can use our range of healthy recipes to create delicious healthy meals, and our meal and exercise planner as a template for your weekly plan.

For further information, a health professional or Accredited Practising Dietitian can give you specific advice about your diet, including what to eat if you’re trying to lose weight or managing any health conditions.