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Published 29th November 2017 by

We all know that consuming too many calories can lead to weight gain, but what exactly is a calorie?

If you are cutting back on calories in a bid to lose body fat, it's a good idea to know how this works towards weight loss.

The scientific definition of a calorie is:

The amount of energy required to raise the temperature of a kilogram of water by one degree Celsius.

You will have seen food packaging listing calories as kcal. This is because, in a nutritional context, the term calorie refers to the kilogram calorie, so look out for the total kcal content on food packaging. Sometimes values are given in kilojoules (kJ).

Foods are given calorie contents to define their ability to give us energy. If we don't put enough energy into our bodies, we need to source it from somewhere else to keep going. Our bodies are clever in that if we run low on calories, it will draw on energy reserves to stay active.

Hmmm... Doughnuts

Hmmm... Doughnuts

Following a low-calorie diet creates a calorie deficit which forces your body to revert to using alternative energy stores. We know that 1 kilogram of body fat is approximately equal to 7,700 calories, so it would seem reasonable to assume that for every 7,700 calories we burn, we burn 1kg of body fat, but it's not that simple.

There are three main food groups, or macronutrients, that we consume on a daily basis.

  1. Carbohydrates which contains 4 calories per gram.
  2. Protien which contains 4 calories per gram.
  3. Fat which contains 9 calories per gram.

Our bodies don't simply choose to draw upon fat for calories when we are in deficit, instead it comes from many sources, and a large deficit can actually lead to weight gain as the reduction in calories will put the body into "starvation mode" when it will store every last calorie as fat because it thinks food is scarce.

While a calorie deficit won't automatically lead to weight loss, eating more calories than we need will certainly lead to weight gain.

Unfortunately, there is no golden rule for weight loss, but these tips can help.

Build Muscle and Eat More Protien

Protein is the food group needed to build muscle, and muscle uses more calories than fat to survive, and lean muscle burns fat for energy. Protein also contains a hormone called glucagon which additionally helps boost the fat burning process.

Aim to eat around 0.45g of protein per pound of body weight or 1g per kilogram of body weight.

Roast Chicken

Roast Chicken

Don't cut carbs!



Low-carb and carb-free diet fads are not the answer to sustained fat loss. Carbs are an essential part of daily nutrition and the first choice of energy for many organs, such as your brain which by itself needs nearly 500 calories per day to function.

What you should do is banish complex processed carbs and replace them with healthy, low glycemic index carbs such as whole grains, lentils, pulses and dark fibrous veg like broccoli.

Ditch the Sugar

Sugar is everywhere, and this nasty ingredient will make you put on weight and keep it on. Sugar is not easy to eliminate as the sugar industry has all kinds of tricks to disguise it in their products. Avoid anything which says sugar, concentrated fruit juice, corn fructose, corn syrup, dextrin, dextrose, Diatase, fructose, galactose, glucose, hydrolysed starch, maltodextrin, maple syrup, sorbitol, sucrose. These are all names for sugar!

Birthday Cake

Birthday Cake

Be aware of hidden sugar as well. Fruit and fruit juices although natural, contain high levels of sugar so don't eat too much.

Try switching out syrups and white sugar for natural honey. Honey has a lower calorie count and has other nutritional benefits which regular sugar does not.

Don't Diet!

The true key to weight loss success is to make it your healthy lifestyle, not a diet. Being on a diet implies that at some point in the future you will be off the diet, back to your old habits and putting on weight again. You will be stuck in this cycle. Instead, make your diet part of your healthy and active lifestyle and make it last.



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