Can Weight Loss Really Contribute to Carbon Emissions?

In a shocking new study, researchers found that weight loss can possibly be contributing to the world's carbon emissions problem.

Even though weight loss is a major topic considering the current worldwide obesity epidemic, many health professionals cannot actually tell you where body fat goes when people shed some serious poundage. More than 50 percent of the surveyed doctors, dieticians and personal trainers assumed that this missing mass is converted into energy or heat, but according to new research, that's not the case.

"There is surprising ignorance and confusion about the metabolic process of weight loss," researcher Andrew Brown, from the University of New South Wales (UNSW), said in a news release.

"The correct answer is that most of the mass is breathed out as carbon dioxide. It goes into thin air," said the study's lead author, Ruben Meerman.

The report published in the British Medical Journal shows that losing 10 kilograms of fat, for example, requires 29 kilograms of oxygen to be inhaled, a metabolic process that in turn produces 28 kilograms of carbon dioxide (and 11 kilograms of water).

"The misconceptions we have encountered reveal surprising unfamiliarity about basic aspects of how the human body works," the authors said.

If you follow the atoms in 10 kilograms of fat as they are 'lost', 8.4 of those kilograms are exhaled as carbon dioxide through the lungs. The remaining 1.6 kilograms becomes water, which may be excreted in urine, feces, sweat, breath, tears and other bodily fluids, according to the study.

So what does this mean in terms of global warming and the accumulation of carbon dioxide, an abundant greenhouse gas, in our atmosphere?

"This reveals troubling misconceptions about global warming which is caused by unlocking the ancient carbon atoms trapped underground in fossilized organisms. The carbon atoms human beings exhale are returning to the atmosphere after just a few months or years trapped in food that was made by a plant," Meerman explained.

While this doesn't suggest that you think twice before trying to lose weight, it does open your eyes to the inner workings of the human body, and demonstrates a rather unique aspect to the circle of life.

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