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Demystifying Calories

By Marcus Fernandez

And just like that, the Easter holiday period is behind us. Much like other holidays and special occasions, we tend to find ourselves overindulging. The world still turns even after eating Easter eggs, birthday cake, or having one too many sugary drinks. Yet many still struggle to reconcile indulging with maintaining a healthy lifestyle. As is the case with almost every nutrition related question, the answer lies in balance.
Counting calories is not for everyone, but for many it can be empowering. Much like when creating a financial budget, it can force us to take stock. For this reason I have put this blog together to shed some light on calories.

What is a calorie?
If you are unsure what a calorie is, you are not alone. When we speak about calories we usually mean a kilo-calorie or ‘Kcal’ if you read your food labels. These terms are often used interchangeably. Don’t be confused; they usually mean the same thing. A calorie is a unit of energy. To be precise it is the amount of energy required to heat up one kilogram of water by one degree Celsius. Excess calories are stored in the body. For the purposes of simplicity, I will refer to kilo-calories as calories.

How many calories should I have in a day?
It should be simple. If we are burning more calories than we ingest, we should be in a caloric deficit, and lose weight. In actuality, this is where it gets confusing. There are a large number of variables here to work out how many calories we require. Firstly we need to work out our Basal Metabolic Rate. This will tell us how many calories are required to perform all the functions needed to live. Such as breathing, pumping our heart, regulating our temperature etc.

Basal Metabolic Rate (BMR)
A number of BMR calculators or charts can be found online to help crunch the numbers for you. As an example, for a male who weighs 83kg and is 177cm tall their BMR would be: 1864 calories a day.

The next step is to work out Total Daily Energy Expenditure. This is a more relevant measurement because it takes into consideration physical activity. This can also be worked out online or manually. Commonly people simply multiply their BMR by 1.2 – 1.5 depending on their level of physical activity. If we used the above example of 1864 calories and multiplied by the middle rating of 1.35 we would get: 2516 calories per day.

This means an 83kg male who is moderately active should aim below 2516 calories a day to lose weight, and above this figure to gain weight.

In recent years, wearables such as Fitbits and Apple watches can also assist with these calculations.

I don’t see Kcal on food labels only kJ?
kJ refers to a Kilojoule. This is another unit of energy. To convert a kilojoule to a calorie you simply divide the number by 4.2. This will give you a rough conversion.
e.g. 1 x 330ml can of soft drink has 594 Kilojoules which works out to 141 calories.

How many calories are there in the food we eat?
Calories can be derived from 4 different sources:

Fat: 1 gram = 9 calories
Protein: 1 gram = 4 calories
Carbohydrates: 1 gram = 4 calories
Alcohol: 1 gram = 7 calories

Does counting calories work for weight loss/gain?
When used in isolation, and without support, it usually does not. Here are three reasons why:

1. All calories are not created equally. We need certain levels of fat, protein, and carbohydrates to lose/gain weight and be healthy. Counting calories usually does not consider macro-nutrient needs. 500 calories from a piece of fried chicken is different to eating 500 calories from grilled chicken, a garden salad and a generous serving of quinoa. This is not to mention the differences in vitamins, minerals, fibre, and other goodies our body needs to stay healthy.

2. Counting calories is difficult when you did not cook the meal yourself. This can take some of the fun out of going out to dinner or socialising. Although, once done for awhile, one can get quite proficient at estimating. The key is not to lose sleep trying to be pedantic about it. Again, apps, website, and wearable technology can also assist with calculations making the task a little more manageable.

3. Lack of food variety. The trap many fall into when counting calories is to eat the same foods over and over again. Once calories are counted for a certain meal, it can be tempting to eat the same thing often. Cooking in bulk, and portioning out exactly the same thing for days. This can bring some short term assistance to meeting goals, but can lead to nutritional deficiencies, boredom, and even resentment.

If counting calories does not work, why should I be pay any attention to it?
Counting calories, or at least being aware of them, can be used as a tool. In Australia today, caloric information can be found in almost everything we consume. There is no ‘silver bullet’ to health, but with a number of tools, we can be empowered to make good food choices. This helps us to reach our goals, and plan social gatherings with confidence and without guilt.

More about the author

Demystifying Calories
Marcus Fernandez

Marcus has been involved in the health industry in one way or another for close to 20 years. Starting out working in gyms and health food stores before getting his degree in nutrition. He later went onto complete a Master of Business Administration (Public Health).

Since then he has split his career between private practice and public health.

Marcus specialises in weight management and sports nutrition. He has helped many clients over the years achieve their goals, and continues to do this as a passion of his. He understands many people have lost their pre-pandemic routines, and is committed to creating innovative ways to help people achieve their goals.

Marcus also works in the field of intolerances. Especially focusing on fructose intolerance, which often goes undetected as a lesser known condition.