Fitness Rush Personal Training Blog

Weight vs Fat loss

Weight vs Fat loss

Is all of your weight loss from fat? 


The common myth of being able to lose an incredible amount of weight in a matter of weeks is being jumped upon by fitness trainers and supplement companies alike, who want to entice you into using their products.

Sorry to those whose sales might take a hit from consumers knowing the reality of Fat Loss after being led down a path of deceit, but yet again, here I am to unveil the truth of what really happens when you lose a stone in a week.

Yes, it is possible, but is it healthy for you? Definitely Not!

So, after following the miracle plan designed by your trusted fitness professional, you step on the scale after a week and cannot believe your eyes. All of those green smoothies, rice cakes and hunger pains have paid off, you will be your younger fitter self in no time. So as promised, you have just lost a stone of Fat in just one week. That sounds too good to be true and unfortunately it is.

This may look like an amazing achievement but in reality, it’s just unrealistic and can have serious health implications for your body.

So, if it's not all Fat, what else could it possibly be I hear you ask?

Not to say some of it wouldn't be fat, but if we look at the calculations behind fat loss, things should become a little clearer. 

As 3,500 calories equals approximately 1 pound of fat, it's estimated that you would need to burn around 3,500 calories to lose 1 pound.

So, if we look at the calories you need daily to maintain your weight and spread it across the week, we can then begin to calculate how many calories less you will need to consume to reach your fat loss goals.

To find your daily needs, your everyday activities will need to be taken into consideration to show how many calories will be left after exercise and daily tasks have been completed. The calculation is known as TDEE or total daily energy expenditure, which can easily be calculated on a number of online calculators.

Once your energy expenditure has been worked out, you then know by eating 500 calories less will give you a pound fat loss each week.

So, if you have a very inactive job and complete no exercise, your calorie intake could be lower than 1800 per day. This would mean, you would need to create a 1000 calories deficit a day, just to lose 2lbs of fat.

This is now making that stone of weight loss even less likely to be all fat. In fact, we are a whole 12 lbs off the science-based fat loss of 2 lbs weekly by using the dramatic calorie decrease of 1000 per day.

To put it into perspective, the average female needs 1500 calories daily to survive in a coma, so you would need to consume half of that to reach a 2 lb fat loss weekly.

Sound dangerous? Probably because it is!

Most of the dangers come from what you're actually losing during your dramatic weight loss.

So here is what actually contributed to the weight loss on your scales



Something you simply can't live without, but the first thing your body wants to get rid of when that crash diet begins.

This is due to our stress hormones being raised, which causes our bodies to drain water quickly. Water obviously weighs and will be the first number off the scales.


Similar to water weight in the fact they work together. In simple, glucose (sugar) is stored as glycogen and is easily accessible for the body to use for energy. This is the storage system your body will use first before anything else. During exercise, in between meals and through the night are examples of when glycogen will be used primarily.

Through crash dieting, your body will use glycogen stores very quickly due to the lack of essential energy connected to reduced calorie intake. The less there is to use, the more your body will want it and as glycogen is stored alongside water, it can increase water loss which will speed up the weight loss process but not in a good way.


This is the most crucial loss which can lead to the largest detrimental affects. 

Due to the increase in stress hormones through dramatic weight loss, the body needs to access protein for a quick dose of energy.

Not only can protein be used to build muscle, but it can also be broken down into sugar to replace the glucose you have been depriving yourself of and when your body faces starvation, it will use more protein (muscle) than body fat.


I know this might seem slightly extreme, but you deserve to know the whole truth and nothing but the truth.

Completing low calorie diets have shown to use more nutrients from your bones which can affect weight but more crucially weaken bones, increasing the risk of fractures.

If you want strong bones, you need to consume those important nutrients.


And it doesn't stop there!

That stone of weight loss over the course of one week doesn't take into consideration the amount of minerals which are lost through water loss and with this, important electrolytes like potassium, sodium and magnesium are also lost, leaving you feeling drained.

This feeling is definitely not worth the leaner look you have been dreaming of. Good things come to those who wait.

What happens when you reintroduce your normal foods?

Over the period of your calorie cutting, your body will react, but not in the way you have been advised. This dramatic approach to weight loss actually slows down your metabolism to conserve energy rather than speeding it up to burn fat, as with more balanced diets.

This is mainly why the fitness professional you see strutting their stuff on social media,

will eat smaller meals spread throughout the day opposed to consuming all their daily calories at once. This then keeps your metabolism working regularly in order to use the energy provided by your food.

So, once you reintroduce your usual food to your diet, your metabolism will be too slow to keep up with the need to turn the calories into to energy, eventually storing the excess into fat in your liver.

What's the answer?

I can't speak highly enough of a healthy balanced diet, full of nutrients and minerals. This will be the key to becoming fit and healthy, giving you the energy to complete increased exercise, allowing you to create your 500 daily calorie deficit and eventually reaching your 1lb fat loss per week.

Just think, over 6 weeks, you would have lost 6 lbs of actual fat.

Be patient and the results will come, just remember - Rome wasn't built in a day!