In this article, you will learn 5 different ways in which your body can trick you with “fake” weight loss results on just about any weight loss diet. I call these results fake, because they can make it look like you’re losing a lot of weight even when you’re hardly losing any body fat at all.
In other words, fake weight loss is any weight you might lose that won’t come out of your body fat reserves (such weight is also known as your non-fat body weight, or your lean body mass). Many rapid weight loss diets (or crash diets, if you will) take a huge advantage of this. They trick you with an illusion of fast weight loss, but as soon as you’re off the diet, you gain most of the lost weight back.
This is nothing new, we all know this as the dreaded yo-yo dieting effect. Except, only a handful of people understand exactly why this happens on so many fast weight loss diets.
In this article, I will use a combination of weight loss science and personal experiments to show you what actually happens in your body during (and after) most crash diets.
I will not only explain the 5 five different sources of fake weight loss results in your body, but I’ll also try to estimate by how much each of these 5 sources can mess up your weight loss results.
1. Dehydration (loss of body water)
Back in 2004, I did an extreme weight loss challenge to demonstrate how to lose the most weight in one day. I have shown it’s possible to lose almost 20 pounds (or 9 kilograms) of weight in just 24 hours. But you should know that what I did IS extremely dangerous. When taken to extremes, dehydration can literally cause your heart to fail , so do not repeat what I did under any circumstances.
I specifically designed my extreme weight loss experiment to lose as much water weight as possible in those 24 hours. I hardly drank any fluids during my challenge, and I used a couple of natural diuretics to force even more water out of my body. On top of that, I exercised in intense heat to lose huge amounts of body water (through sweat).
But given how many calories I actually burned in those 24 hours, I couldn’t have lost a lot more than a pound of body fat. So at least 18 out of the 20 pounds I lost didn’t come from my body fat reserves.
Not getting in any fluids, diuretics, heat, and exercise can all dehydrate in your body. But there are two more specific reasons why our bodies release even more water weight during extreme weight loss.
So let’s get those two out of the way first.
Your body stores energy in a couple of different ways. While a huge majority of that energy is stored away in your body fat reserves, some of it is also stored as glycogen. Burning away your glycogen reserves can also make it look like you’re getting great weight loss results, even when you’re not necessarily losing any body fat at all.
Our bodies store about a pound (or a little over 400 grams) of glycogen on average , but every gram of glycogen also binds about 3-4 grams of water to itself . Because I ate almost no food while exercising for about 6 hours during my extreme weight loss challenge, I wiped out most, if not all of my glycogen reserves. As my body kept burning away glycogen for energy, the number on my scale started dropping pretty quickly. But again, that didn’t mean I was actually losing a lot of body fat, I was simply losing the weight of glycogen (and the water that was bound to it).
Now, while an average person stores about a pound of glycogen, some people can store more than two pounds of it. In other words, if you completely wiped out your glycogen reserves, the number on your scale could deceive you by as much as 7.7 pounds (5 kilograms)  of fake weight loss.
3. Salt (sodium)
Salt, or more precisely, sodium (sodium is the main component of salt), plays a huge role in our modern diets. Even if you’re not adding any extra salt to your food, there’s a good chance your diet already contains a lot of sodium. Sodium isn’t just added to junk foods like pizza and hamburgers, but also to foods like bread, turkey breast, chicken noodle soup, and lots of other processed foods.
According to the Center for Disease Control and Prevention, “more than 75% of the sodium Americans eat comes from restaurant, prepackaged, and processed foods.” 
Okay, but what does all this have to do with fake weight loss results?
All that extra sodium we eat with our food, can force our bodies to hold on to quite a lot of extra body water (to keep that sodium diluted in concentrations that aren’t harmful to your body). Because I exercised and sweat a lot in my weight loss experiment, I also lost a lot of sodium and the water that was bound to it (we lose a lot of sodium as we sweat ).
So pretty much like glycogen, the loss of sodium (and the water bound to it), can trick you into believing you’re losing a lot of weight, even when we’re not necessarily losing any body fat at all.
How much fake weight loss can sodium actually cause?
This information was pretty hard to come by, but based on one study  and my own sodium weight loss experiment, it’s possible to lose as much as 6 pounds (3 kilograms) of body weight if you get rid of any extra sodium in your body.
4. Muscle mass and vital organ tissue
The loss of your muscle mass and vital organ tissue (your vital body mass) is another critical problem you’ll run into, if you try to repeat what I did in my extreme weight loss experiment. Because, once you start running low on glycogen, your body simply can’t extract enough energy from your body fat reserves alone. So after you wipe out your glycogen reserves, your body will have no choice but to start burning away some of your “structural proteins” for energy .
Where will those structural proteins come from?
Proteins are the basic building blocks of your muscles and vital organs. This means your body will literally start eating itself away, just so it can keep you alive during times of extreme weight loss.
How bad can this get?
If I “just” stopped eating food during my extreme experiment, I could end up losing as much as 1 pound (0.5 kilograms) of vital body mass in a single day . But if you keep exercising after running out of glycogen, you can lose over 100 grams of your vital body mass for every hour of exercise. I began my experiment with full glycogen reserves, but then exercised for about 6 hours. So in those 24 hours, I probably lost somewhere around 2 pounds of muscle mass and vital organ tissue in total.
My experiment was extreme, so the destruction of my vital body mass was extreme as well. But the same destruction of your vital body mass will happen on pretty much all but the slowest of weight loss diets (although it won’t be nearly as extreme as in my experiment). Explaining the science on why that happens – and more importantly, how to prevent this without slowing down your fat burn rates – is definitely a story for another article.
So let me just wrap this part up by saying that your final weight loss results will also look better if you’re losing your vital body mass on a rapid weight loss diet. Again, this will have nothing to do with your body fat and is something you’d want to avoid at all cost.
5. Food waste
Let’s take a look at the one last thing that can cause a fake drop of the number on your bathroom scale. I ate almost no food during my 24-hour weight loss experiment, but I could have gone even more extreme. I could have taken a laxative, or use any colon cleansing method to empty out my colon.
If I got rid of all food waste from my colon, this too could make my final weight loss results look even better on paper. I could be “bragging” about an even bigger drop of the number on the scale (without losing any extra body fat).
Colon cleansing is something that actually gets recommended on a lot of different diets/cleanses. Also, if you do any kind of a juice/liquid diet, or simply eat less food overall, you could again be looking at “better” weight loss results at the end of the weight loss diet. The less (solid) foods you eat, the more your colon will empty out, and the better your final weight loss will seem.
How much fake weight loss are we talking about here?
According to one study  – in which they tested “industrial-strength” colon cleansers (the stuff they use in medicine to prepare patients for surgery) – you could end up losing up to 6.6 pounds (3 kilograms) of weight, simply by clearing out your colon.
For the last time, this quick drop of the number on the scale would have absolutely nothing to do with your body fat.
What are the maximum possible fake weight loss results?
To sum up the maximum potential for fake weight loss results on just about any rapid weight loss diet, here’s how much weight you could lose from all 5 sources of fake weight loss results in your body:
- up to 7.7 pounds (5 kilograms) of weight by wiping up your glycogen reserves
- up to 6 pounds (3 kilograms) of weight by reducing the amount of sodium in your diet
- up to 6.6 pounds (3 kilograms) of weight by emptying out your colon
- up to 1 pound (or more with exercise) of muscle mass and vital organ tissue per day.
- on top of all this, you could keep dehydrating your body to the point where it becomes the very last thing you’ll ever do (but I am counting on you to NEVER try anything like that).
Ok, so these are the maximum possible numbers, and they at least roughly add up if I compare them to my real-life results. In my extreme 24-hour weight loss experiment I lost at least 18 pounds of non-fat weight, which can be explained with the numbers above.
If I wanted to precisely measure how many of the 18 pounds I lost came from each of the 5 possible sources, I would need access to some pretty expensive & complicated equipment. But exact number aren’t important. The important thing is that you now have a good enough idea of just how big of an weight loss illusion crash diets can create.
And what happens when you break off a rapid weight loss diet and return to your normal diet?
The real reason for fast weight regains after a crash diet
If you return to roughly the same diet you were on before you started a crash diet, all the non-fat weight you lost during the diet will return pretty quickly.
Your glycogen reserves will refill, your body will regain the water it lost because of dehydration, you will gain back the sodium-bound water weight, and your colon will fill back up again. In my extreme weight loss experiment, it only took two days to gain back almost all the weight I lost (but I did eat more food than I normally do).
Now, if you do a crash diet and then start eating too many calories once you’re off the diet, you WILL gain back any body fat you lost over time (and likely add some on top). But those first couple of pounds you gain back very quickly will have nothing to do your body fat.
The only way to make sure if a diet has actually helped you lose body fat instead of just dropping your non-fat weight temporarily (or worse, destroying a lot of muscle mass and vital organ tissue), is to measure your body fat percentage before and after the diet. The important thing is that you now understand what happens “under the hood” if you do a fast weight loss diet and then quickly gain back some weight.
You will no longer think that the diet didn’t work, that you did something wrong, that your metabolism has been “crippled” by the diet, or even that you’ve lost and regained pounds and pounds of body fat in a matter of days (which is simply not possible).
Can crash diets deliver only fake weight loss results?
Let’s put something into perspective. Even though I lost “just” a pound of body fat in my 24-hour weight loss challenge, it would still take a week or two to lose the same amount of body fat on most standard weight loss diets.
If my experiment didn’t involve dangerously dehydrating my body and destroying a lot of muscle mass and vital organ tissue in the process, we could actually be talking about one of the fastest fat burn methods on the planet (but we can’t, cause what I did is simply too dangerous).
Crash diets have gained a very bad reputation because of the rarely understood yo-yo effect, but some well-designed rapid weight loss diet can actually target your body fat reserves extremely well (and do so without the destruction of your muscle mass and vital organ tissue).
The problem is, only a handful of rapid fat loss diets have ever been scientifically proven to be able to deliver those kind of results . I have to wrap this article up, but if you’re interested in more information on this, look up muscle sparing fasting (or as scientist call it, protein-sparing modified fasting).
This was a long read, but congratulations for making it all the way to the end.
My hope for this article is to eliminate at least some of the confusion, frustration, and disappointment people usually run into when they regain weight after a rapid weight loss diet. If you know someone who ever suffered through such feelings, do them a favor and share this science-based explanation of the yo-yo dieting effect with them.
Featured photo credit: pixabay.com / geralt via pixabay.com