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Most of us are well aware that weight loss is hard.

You can slave away at the gym and eat barely anything and lose a kilo at most.

So why was it that on Sunday night’s episode of "I’m a Celebrity.....Get Me Out Of Here," Casey Donovan was able to lose a massive 17kg, Dane Swan dropped 14kg, and Steve Price shed more than 10kg — while Ash Pollard and Tegan Martin only managed just a tiny few kilos off on the scale over the same time frame?

Here are some of the reasons for the weight loss outcome:

The more you have, the easier it is to lose
The body works like a machine when it comes to burning energy. This means the more body fat you have, the more likely it will be burnt as there is plenty of extra.

On the other hand, when you have relatively small amounts of extra body fat, the machine will work a lot more efficiently to preserve energy.

It is for this reason that larger people can lose seemingly massive amounts of weight compared to a few kilos for those who only have a little extra to spare even though they are following the same diet and activity regimen.

The more you have, the more fluid you have

The actual process of burning body fat is a demanding metabolic process, which means the body has to work pretty hard to do it. This is part of the reason that losing body fat is tough for anyone.

For people who carry a lot of extra body fat, and for those whose cells are packed full of extra carbohydrate in the form of glycogen, the body will also be storing a significant amount of extra fluid.

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