Where did the fat go?


You have seen at least one person who was overweight or fat and has lost fat in a healthy manner through a structured diet and exercises!

You lose weight when there is a calorie deficit (i.e your calorie in is lesser than your calorie-out). More specifically, to lose fat without losing muscles (which is the healthy way of losing weight), you need to be on a structured calorie deficit with right macro nutrient mix and physical activities

Where did all that fat go?

Is it melted and excreted out through urine and feces? Or does it disappear just like that!? Some even think fat is converted into muscles, as one exercise (which is terribly wrong)

Yet another popular misconception among fitness trainers and even dietitians, is that the missing mass is converted into energy. (which is a violation of the law of conservation of mass)

Alright, so where did all that fat go!? Let us understand the metabolic process of weight loss or fat loss in particular –

A vast majority of the fat is exhaled out as carbon dioxide.

Yes!!! Roughly 84% of the total body fat one loses is exhaled by him/her as carbon dioxide, while the remaining leaves the body as water as bodily fluids such as urine, sweat, etc. in other words, if you lose 10 kg fat, then 8.4 kg comes out through the lungs as Carbon dioxide and the remaining 1.6 kg turns into water.

To metabolise 1 kg of fat, you need 2.9 kg of oxygen to be inhaled. The corresponding metabolic activity results in 2.8 kg of carbon dioxide and 1.1 kg of water being produced.

i.e    1 kg fat + 2.9 kg O2  ==> 2.8 kg CO2 + 1.1 kg H2O

before and after a chemical reaction, there is the same amount of mass..it just changed form!

Hold on! Hold on! Hold on! 🙂 

I know what you are thinking!!

NO! You will not lose fat by simply breathing in and out more. Trying to huff & puff unnaturally will only cause hyperventilation and make you go dizzy or may even faint. However, the good news is that exercise increases the carbon dioxide output from your body.

In a nutshell, the lungs are the primary excretory organ for fat

By the way, did you know that you never lose your fat cells!? They just shrink as you lose weight and they are pretty much capable of storing fat once again if need be. 

Intrigued? Do, check out – https://www.nuvovivo.com/blog/fat-cells-do-not-die/

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