Ever wondered, where does the fat go when you lose weight? If you are still reading this blog, you are in for a chemistry lesson in the metabolic process of weight loss, and fat burning. If you have been “dieting” and “exercising”, counting macros and calories, and believing in that math (or myth) of Calories In, Calories Out. You may be led to believe that the fat converts to energy when you exercise. Well I came to find out a long time ago that is not true. I am just not sure why I never wrote about this, until now.

So here goes the TLDR version. When your body starts burning the fat, it expels excess fat in form of carbon dioxide and the fat cells shrink. So you theoretically “breathe out” the fat while burning it.

Misconceptions about Fat Burning

Check out how mis-informed doctors, dieticians, and personal trainers were about fat burning. Look at their responses to this question “When somebody loses weight, where does it go?” (Correct answer CO2).

where does the fat go when you lose weight
Source BMJ 2014;349:g7257

I am not playing doctor. Any advice you read on this blog cannot be used as a substitute for professional medical advice. If you are experiencing a health condition please reach out to a qualified healthcare professional. I repeat, do not use this blog as medical advice to treat yourself or others.


The Science of Fat Burning

This study was published in 2014 by Robert Meerman and Andrew Brown in 2014. And they did some pretty cool calculations to show exactly how fat burning works in numbers. Very Simply speaking – When somebody loses 10 kg of fat (triglyceride), 8.4 kg is exhaled as CO2. The remainder of the 28 kg total of CO2 produced is contributed by inhaled oxygen. Lungs are therefore the primary excretory organ for weight loss.  Losing weight requires unlocking the carbon stored in fat cells!  

Where does the fat go when you lose weight?
BMJ 2014;349:g7257

Before there is fat burning, there is another secret quick win.

Lose That Water Weight

And You can do this by drinking a lot of water. We usually go for a muffin instead of water. And hence we are constantly dehydrated. When you do not drink enough water it forces your body to store water. Which makes you feel and look bloated.

So, easy peasy – just the way I like it. When in doubt drink water. When hungry, drink water. Drink water before a meal. Drink your “Weight” out!! I talk about this in more details here – Hydration Matters: Drink More Water.

The Weight You Want to Lose

Now that you have lost the water weight, next comes the “Fat” you want to burn. And as you learned above – When your body starts burning the fat, it expels excess fat in form of Carbon Dioxide. Hence you burn fat simply by existing. You exhale out the Carbon Dioxide while you are living (breathing). And the fat cells shrink.

Is Counting Calories the Answer?

The question now becomes how can you accelerate the fat burning. An average man needs 1500 calories per day to live, and a woman needs 1200 calories. However counting the calories itself for simplicity’s sake is alright, but what is even more important than that is where your calories are coming from?

You can get those 1200 (or 1500) calories from the unhealthiest white bread made out of all-purpose wheat flour or processed foods (which literally gives you no nourishment and lots of chemicals for your digestive system to process.)

Or you can get those calories from Healthy and Nutrition Dense foods, herbs, spices. These foods not only give you nourishment in many different ways, but they also give you a long and healthy lifespan.

Every one is getting older. You might as well age as healthy as you are able to.

So how can you apply this information for weight loss?

You could DIY Your weight loss using the methods I talk about here – Easiest Way To Lose Weight & the Quest For a Permanent Weight Loss Solution

And while I do not want you to go crazy about counting and tracking calories and foods, I want you to care about measuring your weight and waist Importance of Weights and Measurements – Quantified.

It takes a tremendous amount of Exercise to burn small amounts of Calories. Hence Exercise is definitely not the answer.

Physical activity as a weight loss strategy is, therefore, easily foiled by relatively small quantities of excess food.

BMJ 2014;349:g7257

And follow this powerful lesson on micro workouts No Time to Exercise? Learn about The 5-Minute Exercise here. Or consistent every day walking Health Benefits of Walking.


Do you have a desk job? You sit at your desk all day and the job stresses you out. You follow through with a cycle of stress eating the first thing you get your hands on. If you want to finally lose all your excess weight, burn belly fat, increase zen, support a healthy inflammation response and repair your broken metabolism. And More of this – without giving up great food, without sweating in the gym. Learn more here –  How to start losing your “computer belly” without counting calories, dieting OR sweating in the gym.


Funny, Not True. One would wish the Fat Burning Math was this easy!

Robert Meerman says in this study – For comparison, a single 100 g muffin represents about 20% of an average person’s total daily energy requirement. Physical activity as a weight loss strategy is, therefore, easily foiled by relatively small quantities of excess food.

Jerry Seinfeld Experiment: Don’t break the chain. Post #106


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