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The Truth Behind Weight Loss vs Fat Loss

Are you seeing no change after coming off the scales? Are you struggling to lose that layer of fat hiding your six-pack? Weight loss and fat loss are two terms that are often used interchangeably. It’s time for you to learn the difference between them.

Woman measuring her slim waist to check her weight loss


It sounds simple but a person’s bodyweight is the total amount of weight that person possesses. What people forget to remember is that this total is made up of lots of different substances. Some of these substances include; muscle mass, bone mass, organ mass, fat mass and water. The amounts and proportions of these substances are what account for your total body composition.

When people think to lose weight they have a perception and desire to lose fat mass. In reality it usually comes at a cost of losing muscle mass and water along with only small amounts of fat mass. These results can leave us being disappointed with the outcome.

Whilst attempting to reduce weight, the general assumption is that you must use scales to track the success of losing weight. Although a useful tool, unfortunately scales don't give you the breakdown of what you're actually losing. You don't know if it's fat mass, muscle mass or water.

So when thinking of weight loss, picture it as a general overview of what’s lost. It’s a physical measurement i.e. a number on a scales. These meaurements do not take into account the different types of substances that are lost.


Fats have many important functions in the body so everyone needs a certain amount of body fat. Body Fat is expressed as a percentage. It helps make up your body composition. The percentage indicates what proportion of your body composition is made up of fat.

On average women tend to have more body fat than men. One of the reasons for this is that women need to maintain a higher level of body fat for the reproductive system. Men tend to have a higher muscle mass percentage on average than women for a given weight. This can lead to a lower level of body fat.

Excess fat is stored around the body and is known as adipose tissue. There are two main types of fat most responsible for health and appearance. These are visceral fat and subcutaneous fat. Visceral fat is the fat stored around organs. Subcutaneous fat is stored between the skin and the muscle. To lose fat we must breakdown and reduce the stored fat.

Despite the wild claims, wild ab workouts or magical health formulas cannot burn belly fat. We cannot actually choose where we want to lose fat from. We cannot spot reduce our body fat. Instead, it's all about choosing the right diet plan and maintaining regular exercise. You need to create a calorie deficit.


There are many different ways to measure body fat. Some are more fancy. These include; DEXA scans, Air Displacement Plethysmography and Hydrostatic Underwater Weighing. But these measures aren’t always accessible to the everyday individual. Generally speaking, body fat measurements are only predictions based on the equipment used.

Bioelectrical Impedance Analysis-BIA

BIA involves running an electric current through a scale and or a handheld device. Quite often seen in big commercial gyms such as Pure Gym and The Gym Group. With a large margin for error and different variables that can affect it's validity or reliability, this is one of the less accurate measures to determine body fat levels.


Skinfolds can be a very practical and cheap way to measure body fat. It involves having various skinfold sites measured with calipers to determine body fat levels.

The accuracy of your results is dependent on the quality of calipers as well as the experience of the person leading the test. If done by a qualified practitioner results will be more accurate.

It’s worth noting that the sum of the skin folds could be more useful than the actual percentage. This is because fat tends to shift around the body and the percentage is an algorithm based on equations. The sum is the total of all skinfolds added together.


Taking regular pictures of your body can be a great way to measure progress. It’s simple and requires no fancy equipment. Pictures don’t give you a mathematical figure that lets you know how much you’ve lost. You can look at the picture and see aesthetic progress. Visible appearance can be an important indicator, seeing any changes over time. For greater accuracy constancy is important. Try to keep as much as you can the same. The type of clothes, timing of photo, lighting and angle can all impact the effect of the photo. The more you keep the same the easier it is to see the differences in the pictures.

The scale

There is a lot of speculation around the usefulness of using scales. On a daily basis your weight can fluctuate. Hormonal fluctuations, varying sodium intake, different amounts of dietary fibre and food sitting in the gastrointestinal tract can all affect what you weigh. So should people use scales? Research indicates that people who weigh themselves more often are more likely to stick to a diet and exercise plan, as well as keep the weight off. To improve measurements, consistency is important. Sticking to the same time of day is the biggest one to remember. Try to weigh yourself immediately after you wake. This gives the body time to settle overnight.

It is important to take into consideration your body composition when thinking of using scales with fat loss. Someone that's overweight attempting to lose fat will show a decrease on the scales as they lose weight/fat. An athlete who's body fat percentage is already reasonbly low but wants to reduce their fat mass, the scales may be misleading. The measurement on the scales may go up (put on weight) as muscle mass increases, yet body fat may reduce.

A better approach might be to use a combination of these measurements to get a better idea of what your body is doing in relation to weight loss or fat loss.

Young male holding dumbbells with high muscle mass and low body fat.


Muscle Mass

If the end goals is to lose weight then maintaining muscle mass or even increasing muscle mass may not be for you. Muscle weighs more than fat so a reduction/increase in muscle mass will likely affect the measure on the scales more dramatically.

There is a big misunderstanding surrounding body fat and muscle mass. There are very few scenarios where it’s possible to both lose body weight whilst gaining muscle. So it is suggested to focus on either one at a time to get better results. This is because building muscle requires a calorie surplus. Losing fat requires a calorie deficit. So like two bulls locking horns the two don’t go well together.

Having a higher amount of muscle mass impacts your basal metabolic rate (BMR). This is because there is more active tissue. This increases the rate your body burns calories. So having less muscle mass means having a lower BMR, reducing the calories burned throughout the day. The mitochondrion cells found in muscle are one of the locations responsible for breaking down fat. So the more active muscle mass you have, the more fat that can be burned. This benefits fat loss. Regular exercise can also improve mitochondria function again aiding the fat loss process. As previously mentioned muscle weighs more than fat so having a higher amount of muscle mass means a higher bodyweight.

Losing muscle mass can result in the nutrients consumed through your diet not being properly utilized. The more muscle mass the more nutrients needing to be absorbed and used by the active muscles. Losing muscle mass can increase the chances of excess nutrients being stored as fat.

Water Loss

Our bodies are made up of around 60% water. Our muscles contain 70% water and other body systems also contain high amounts of water. This means that any change your bodies water levels can have a dramatic impact on what you weigh.

Carbohydrates keep around three times as much water as any other type of macronutrient. If you reduce your carbs, you reduce the amount of water retained also. This is one of the biggest reasons why people see almost an instant reduction to their bodyweight when they go on a low-carb diet. Yet this is not related to fat loss.

Woman feeling the gap in her jeans from weight loss. A diagram comparing the differences between a weight loss plan compared to a fat loss plan.


Although used interchangeably hopefully now you can see the clear difference between weight loss and fat loss. When most people mention loosing weight what they tend to actually mean is fat loss. When people want to lose weight they do it for the feel good look good element that comes with it. They also want to improve their health.

Understanding how can better track your progress, you can better understand if you’re burning fat or are you losing water and muscle too. Understanding how muscle mass can help you lose body fat can help determine what exercise routine might best help you achieve your fat loss goal.

Think about what you’re after, is it weight loss or fat loss? Once you’ve established that it makes it easier to choose the right tools to help guide you towards your goal.

There is a lot to take on board after reading this, so feel free to ask any questions you may have in the comments section.

Further Still you can Learn More About Weight Loss in my online guide.


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