Fat Loss Vs. Weight Loss: The Truth About Weight Loss

By JC Deen



Weight loss and fat loss are not created equal even if they seem similar at first glance. One can lose weight without losing fat. And one can lose fat without losing much weight. But just because you lose weight, it doesn’t mean you’re losing body fat.

Because let’s face it — no one wants to just lose weight, we want the weight that’s lost to be fat.

If you want to know the proper way to make sure the weight you lose is fat, and not muscle, keep on reading…

What Is Body Weight?

Your body weight is made up of your entire being, not just your body fat alone. How much you weigh has nothing to do with who you are as a person, your self-worth, or anything else outside of how much the scale reads out when you step on it.

You might use kilograms, pounds, stone, or some other method, but it’s all the same.

Therefore, your body weight is a mixture of the following:

  • Skin
  • Bones
  • Muscle
  • Nerves
  • Connective tissue
  • Internal organs
  • Water
  • Fecal matter

So when looking at your body weight only, we can’t accurately assess your body composition.

Body composition is the proportion or percentage of fat and fat-free mass in the human body.

For instance, skin, bones, nerves, connective tissue, organs, and skeletal muscle are all parts of the fat-free mass in the body.

Here’s an example: a man weighing 200 pounds at 6 foot tall is going to have a different body composition than a woman weighing 200 pounds at the same height.

We’ll get into this more in depth in a second, but just know this for now.

Your weight is everything that your body is made of, not just fat.

Now to the next logical question:

What Is Weight Loss?

Weight loss is a reduction in your body weight, regardless of the means of how you go about losing that weight.

For instance, weight loss can come from any of the following bodily functions:

  • Sweating (it’s not unheard of to see people lose upwards of 10 pounds after a long run or workout where they sweat a lot)
  • Peeing (just like sweating, this is water loss)
  • Pooping (yes, your poop has weight)
  • Fat burning (more on this in a second)
Just remember: losing weight is not the same as losing fat. From my previous example, you can lose water weight through peeing or sweating, or when you relieve yourself while catching up on your reading. But just because you took a dump and now weigh less as a result, you only lost weight, not fat.

What Is Fat Loss?

Fat loss is exactly what it sounds like. It’s the fat magically leaving your body through diet and exercise. In this case, fat loss almost always correlates with weight loss due to the nature of how the body works in terms of energy balance (more on this in a moment) and energy expenditure.

The way fat loss happens is through a reduction in calories ingested, either through deliberately eating less than you normally do, through exercise, or a combination of the two.

Fat loss is a product of what’s known as a calorie deficit. In short, everyone has a baseline level of calories required to maintain their body weight. This is known as your maintenance caloric intake.

And in order to lose fat, you have to eat less than what it takes to maintain your body weight. This is the primary way fat loss happens. Now I’ve written on this extensively and you can read all about how this process works in my fat loss guide.

Why Losing Weight Doesn’t Mean You’re Losing Fat

Repeat after me: Losing weight doesn’t guarantee you’re losing fat.

Many people will often confuse fat loss with weight loss. And because we’re so obsessed with body weight in our culture, the idea of reducing your weight is always associated with being less fat.

But just losing weight alone is no guarantee you’ll lose body fat.

In fact, there are a lot of people who lose weight relatively quickly and they’re convinced they’re losing a lot of fat when in reality, they’ve lost mostly water and muscle size because they’ve recently manipulated their water and carbohydrate intake.

Here’s an example…

You’ve probably seen a friend or family member go on a diet and lose 15 pounds in a span of a few weeks. From the outside looking in, most people will be amazed at how fast this weight loss happened.

And while it’s nothing to scoff at, we have to be realistic with what’s actually happening.

Chances are this person who just lost 15 pounds made a few changes, such as:

  • Increasing their water intake
  • Cutting out carb-heavy foods and/or fast food
  • Started exercising regularly

When you combine those activities, you have a very good recipe for quick weight loss from losing water weight and a reduction in glycogen stores.

When you increase your water intake, you will begin to excrete more water. Oftentimes, people will try to drink up to a gallon of water per day, and that often over-hydrates them, causing them to pee every 20 minutes.

As you cut out carb-heavy foods, you will begin to lose muscle glycogen because you’re not replacing it with the typical foods full of carbs you may have been eating. Glycogen is stored in the muscles and when you lose glycogen, water goes with it.

And when you cut out fast food and eat more whole foods, you’ll automatically slash your sodium intake, which will tend to help you drop lots of water weight because excess sodium will tend to cause water retention. People will often say they feel way less bloated than before when switching to whole foods and that’s largely because of the lower sodium intake as well as a lower calorie intake, in general.

Lastly, as people begin exercising more, they’ll do two things that contribute to weight loss.

They will:

  • Deplete muscle glycogen (which isn’t being replaced by typical carb-heavy foods).
  • Excrete more water through sweating.

And this is a great recipe for quick weight loss, but there isn’t much fat loss happening during this initial weight loss period and the progress will typically stall fairly quickly.

You’ve probably heard this line: “I’ve tried everything and nothing works.”

And it’s usually uttered by those who change their diet drastically, lose some weight in the beginning and then can’t make any more progress. After a few more weeks, they try something else and run into the same problems of making quick progress initially, followed by a long plateau.

This is why we should focus more on fat loss than weight loss in order to be successful in the long term.

Why Fat Loss Almost Always Means You’ll Lose Weight

For the majority of the clients I’ve worked with, losing fat almost always correlated with weight loss. The reason for this is because of how the body works through anabolism and catabolism.

In short, anabolism = growth (constructive metabolism) through the synthesis of new tissue in the body.

For example: when someone is bulking to build muscle, they’re gaining weight in the form of new muscle tissue, as well as body fat.

Catabolism = the breakdown of bodily tissues (destructive metabolism).

For example: when someone is eating less than their maintenance intake, their body breaks down fat for fuel, which causes them to lose weight.

Let’s think about this logically for a moment.

If you put yourself into a catabolic state by eating fewer calories than you burn, you’ll lose fat as long as you follow the main principles, all of which I’ve covered in my free fat loss guide.

Those principles are:

  • A moderate caloric deficit
  • Regular resistance training (2-4 days per week)
  • Sufficient sleep (8-9 hours per night)
  • Adequate recovery (you have to take days off)
  • Consistency (the mother of all progress)

If you’re consistently losing fat, you’re going to be losing weight.

But there is another phenomenon that happens every so often. And that’s what we call a body recomposition.

What Happens When You Lose Fat But Your Weight Doesn’t Change?

Body recomposition is a process where you burn fat and gain muscle at similar rates. This is when you notice more muscle and less fat over time while staying within a 5-10 pound weight range.

For example: let’s say someone is 190 pounds at 20% body fat. After 6 months of working out and eating a better diet, they still weigh 190 pounds, but they’ve reduced their body fat percentage to 14%.

When you do the math, that’s a loss of 11 pounds of fat and a gain of 11 pounds of muscle.

Of course, this is the holy grail of transformation experiences. All the ads online promise you will torch fat and build insane amounts of muscle by following a very specific and peculiar diet.

However, most people won’t burn fat and build muscle at a similar rate. This type of progress is mostly reserved for those brand new to training (those with very little training or diet experience in the past).

Most everyone else will do better by focusing on one goal at a time and will definitely lose weight when they lose fat. This is truer the heavier you are and the more fat you want to lose.

So don’t expect to magically lose fat and build muscle at similar rates. Just so you know, losing fat is typically much easier than building muscle from a physiological perspective.

How To Accurately Track Fat Loss

Now you know that weight loss isn’t the same as fat loss. But how do you track your fat loss accurately? How will you know that you’re losing fat, not just weight?

There are four ways to ensure you lose fat as the scale weight does down. And in the rare case, the scale doesn’t budge, you’ll have a foolproof set of metrics to make the necessary changes.

Scale Weight

Scale weight is helpful because if it’s going down on a consistent basis, you have a good indicator the work you’re doing is paying off.

I recommend tracking your scale weight every day and keeping an average. To put this in perspective, I have a client who’s kept his body weight records for 8 years. This may seem excessive, but the data is great to have.

How to do it: every morning, step on the scale in the nude. Only weigh yourself after using the restroom and before eating or drinking anything. Record that number in a spreadsheet every day and then run an average formula.

If your goal is fat loss, and you’re losing weight steadily, you know your diet and training is working in the way you want it to. If the average is not changing or going down on a regular basis, then it’s time to make an adjustment.

Beware of the fact that your body weight is going to fluctuate on a daily basis. It’s not unheard of to gain a few pounds in a day and then lose a few more pounds the next day. This is totally normal and why I recommend keeping a running average of your daily weight to make sure progress is happening.

The last thing you want to do is step on the scale once every few weeks because it won’t give you an accurate picture of what’s really happening with your body weight.

Waist Measurements

This is one of the best methods of tracking fat loss progress because as you lose fat, your waist is going to shrink. The reasoning for this is because we tend to store the majority of our fat on our trunks (waist, hips, thighs). If your waist measurements aren’t going down, but your weight is, there’s a chance you’re not losing that much fat.

However, if your scale weight isn’t moving as much as you’d like, but your waist measurements are going down, then you’re likely losing fat and building some muscle at the same time.

Also, using waist measurements as a way of tracking progress is great because fat loss isn’t always going to be linear. You might not lose exactly 1 pound per week every single week. And your measurements aren’t going to go down every time you take them. However, as you look back over the weeks and months of proper tracking, you’ll have records as proof that what you’re doing is or isn’t working.

For example, I have a client I’ve been working with for 6 months and she’s gone from 157 pounds down to 140 pounds in that timeframe. That’s 17 pounds lost in total, but when looking at her weight on a weekly basis, there were many times where she didn’t seem to lose any weight. In fact, some weeks she gained weight.

But her waist measurements tell the best part of the story.

In that 6 months, she’s gone from a 34-inch waist to a 29.5-inch waist. That’s a loss of 4.5 inches, which is an amazing indicator of how much fat she’s lost from her midsection.


Here’s what’s good about that old pair of pants you can no longer wear… they stay the same size. And this allows you to get a feel for how well your fat loss diet is working. Every few weeks, you can put on a pair of pants, or a shirt that fit well at a certain size or weight. If the piece of clothing fits better or looser than the week or month before, you’re making progress. If it feels the same, you might not be losing fat in the manner you’d like to.

Often times people will notice their current clothes becoming baggier and loose the further they get into their weight loss journey. This is also a great way of seeing your progress in real-time.


Lastly, the tried-and-true method of taking images of yourself can be extremely rewarding, or mentally draining depending on how you look at it. You don’t have to schedule a professional photo shoot or anything. All you need to do is take some mirror selfies or use the timer on your phone or computer camera.

I tell my clients and customers to take images once every two weeks. This way, they’ll have a record for how their body is changing over time.

It’s pretty common for people to avoid taking photos of themselves because they’re embarrassed or feel like the pictures don’t matter. But images are important because when you’re focused on losing weight or body fat, you won’t notice the changes happening because you see yourself in the mirror every day.

Fat loss happens pretty slowly for most people and since the changes are so subtle, you’ll rarely notice them when looking in the mirror.

Here are a few case studies:

From Fluffy to Ripped, Sans the Obsession

fat loss vs weight loss

I remember getting the email with a photo update from Chris at 15 weeks and he said something like “I’m not really sure if I’m making much progress. What do you think?”

That’s why I sent him those photos above next to each other saying “I beg to differ — you’ve made a ton of progress.”

And then we have Salim’s story: How To Lose 15 Pounds Of Fat Without Skimping On The Carbs

fat loss vs weight loss

As you see, Salim made gradual changes over the months and while these look drastic compared side by side, you’re never going to notice these changes in the mirror.

Taking photos is a great way to measure progress because it can help keep you motivated when weight loss starts to feel slow or like you’re not making much progress.

Why ‘The Scale Lies’ Is A Terrible Mantra For Making Progress

People will often say “forget what the scale says!” but that’s mostly because they either:

  • have a negative relationship with their weight, or
  • they operate under this delusion that if they only eat healthy food and exercise they won’t have to pay attention to their weight.

First of all, if you have a negative relationship with the scale, try to entertain the idea of scale weight being nothing more than data. I know it can be an emotional rollercoaster for some, but the more you become emotionally tied to a certain number on the scale, the harder it is to let go of negative feelings around body weight.

And let’s be real — there is no perfect body weight for everyone. Some people feel more comfortable weighing less or weighing more. This is also going to vary a lot depending on how much muscle you have, your bone structure, and how active you are.

The other reason neglecting scale weight is a bad idea is due to the massive delusions about weight loss people have developed. I oftentimes experience this with men I’m coaching.

They will come to me wanting to get lean enough to see their abs. And when they tell me they only have about 10 pounds to lose, I can quickly assess after seeing their pictures, they’ll likely have to lose 20-30 pounds to have a well-defined six pack.

So we have to face the truth… If you’re 20 pounds overweight, you’re going to have to lose weight (in the form of fat) in order to get leaner. Most people are not going to magically replace that 20 pounds of fat with 20 pounds of muscle unless they’re a rank beginner, and even then, it’s not likely.

Why Sleep Is More Important Than Diet Or Exercise

Finally, sleep is the most important macro. You heard that right.

Of course, sleep is not a macronutrient, but when weighed against diet and training, it’s one of the most important factors for changing your body composition.

Without adequate sleep, you cannot recover properly. If you fail to get enough sleep, your stress hormones will rise. And with more stress, the body becomes catabolic.

More stress often means you will lose muscle, see a decrease in performance, which means you’ll lose strength.

You’ll be hungrier, and will have a harder time controlling your diet. The hungrier you are, the more likely you’ll overeat on high-calorie foods that will make weight loss nearly impossible.

And if you try to work out when you’re low on sleep, you run the risk of injuring yourself. If you get injured, you have to take time away from the gym, which means you only delay your weight loss progress.

How does sleep affect fat loss directly?

A study done in 2010 makes this incredibly clear.

Straight from the study:

“During the two-week, 8.5-hours-in-bed phase, volunteers slept an average of 7 hours and 25 minutes each night. In the 5.5-hour phase, they slept 5 hours and 14 minutes, or more than two hours less. The number of calories they consumed, about 1,450 per day, was kept the same.

“The volunteers lost an average of 6.6 pounds during each 14-day session. During weeks with adequate sleep, they lost 3.1 pounds of fat and 3.3 pounds of fat-free body mass, mostly protein. During the short-sleep weeks, participants lost an average of 1.3 pounds of fat and 5.3 pounds of fat-free mass.”

Do you see that?

Those who slept for 5.5 hours per night lost mostly muscle while those who slept 8.5 hours lost equal parts muscle and fat.

Now here’s what these people weren’t doing:

  • Eating a healthy, protein-rich diet
  • Following a structured weight training routine

When you combine good nutrition and a solid strength training program with enough sleep and rest, you will be able to lose the majority of your excess body weight from fat and maintain most all of your muscle mass.

Sleep is the most important part of the fat loss process… yes, even more important than the diet or training because without proper rest and recovery (which happens when you sleep), you cannot reap all the benefits from proper training and nutrition.

To further your understanding of why sleep is so important, listen to this Joe Rogan podcast with Matthew Walker Ph.D., and then read Matthew’s book, Why We Sleep.

Fat Loss Vs. Weight Loss QnA

Here are some general questions with straightforward answers:

Can you lose fat and not weight?

Yes. It is possible and it happens. But unless you’re brand new to strength training and exercise, in general, the chances of you losing fat without seeing much weight loss are pretty low. This is especially true if you have more than 20 pounds of fat to lose.

Does burning fat make you lose weight?

Yes, in most cases because body fat is a part of your body mass. When you burn body fat, you will almost always lose weight unless you happen to build muscle at the same time that you burn the body fat.

How much fat do you lose when you lose weight?

It’s almost impossible to answer because when you lose body weight, you’re not only losing fat, but you’re also losing water that’s stored in the fat cells, and you’re depleting muscle glycogen, which also contains water.

How can I lose body fat instead of weight?

The only way to lose body fat instead of body weight is to build muscle at the same time. The best way to make this happen is to lift weights and to follow a progressive strength training program while putting yourself into a caloric deficit to lose body fat.

Why do I feel thinner but weigh the same?

It’s because you lost body fat but maintained or gained some muscle, so your body weight remained the same.

Why do I look thinner but weigh more?

This is because you’ve lost body fat and gained muscle. Muscle mass tends to be dense and hard-looking compared to how fat looks on the body. Fat is deposited on top of the muscle, and beneath the skin, so when you reduce your body fat, the muscles underneath are more defined and create a thinner look overall.

Is it better to lose inches or weight?

In general, it’s best to lose inches while losing body weight because this is a sure sign you’re losing body fat, not muscle mass.

Why does my weight fluctuate 10 pounds in a day?

Most people’s body weight will fluctuate throughout the day because we all drink water, other beverages, and eat food between the time we wake up and the time we go to sleep. When we go to sleep, we’re spending a period of time (typically 6-9 hours) in a fasted state (which means you haven’t eaten) and most of the weight loss that happens overnight is from water loss. Every time we exhale, we’re losing a tiny bit of water vapor, which contributes to dehydration.

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If your goal is to lose fat and maintain your muscle, check out 4D Fat Loss (for men) and HOT BOD (for women).

JC Deen is a nationally published fitness coach and writer from Nashville, TN. Currently living in the blistering Northeast. Follow me on X/Twitter