When you lose fat, where does it go?

When you lose fat, where does it go?

Picture this: Breathe in and fill those lungs — and breathe out fat.

The image may be an exaggeration, but it’s not much of one.

Matter is neither created nor destroyed. So, the widely held belief that fat is burned off as extra energy or heat, or is converted into muscle, is incorrect, according to researchers from Australia’s University of South Wales. The researchers reported their findings in The British Medical Journal.

To solve the mystery of where fat goes, researchers began with what type of fat we actually lose: triglyceride. In order for you to get rid of it, the fat must be broken down into the atoms that make it up. This happens through a process called oxidation.

When triglyceride is oxidized, it breaks into carbon, hydrogen and oxygen, which the researchers then tracked.

Turns out, a good portion of the triglyceride is exhaled as carbon dioxide. The researchers found that for 10 kilograms of human fat to be oxidized, humans must inhale 29 kilograms of oxygen. When the fat reacts with the oxygen, 11 kilograms of water and 28 kilograms of carbon dioxide are produced.

The researchers think this means your lungs are responsible for releasing your fat. The water produced exits your body in other typical ways: Through your urine, sweat and other bodily functions.

Throughout the day, a 155-pound person exhales at least 200 grams of carbon. When you exercise, you breathe more frequently and deeply, ridding your body of even more carbon. The researchers say that one hour of moderate exercise can remove an additional 40 grams of carbon from the body.

So, next time you exercise, don’t feel bad about huffing and puffing. You’re actually just blowing the fat away.

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