The language of weight loss is one of destruction. We cut calories, slash weight, burn fat — all in an effort to shed those unwanted pounds. But as anyone who has ever studied elementary science can tell you, matter can neither be created nor destroyed. So if that's the case, where do all of those pounds go when you "lose" them?
This question perplexed Australian Ruben Meerman, a former physicist turned TV personality and science educator. Meerman had recently lost a little more than 30 pounds and it made him start questioning where it all went. So he recruited the help of Andrew Brown, a fat researcher at the University of New South Wales, to figure it out. Their results are published in the recent issue of The BMJ.
They started their inquiry with this chemical formula:
C55 H104O6+78O2 —> 55CO2+52H2O+energy
Need a refresher on chemistry? Basically, C55 H104O6 is the chemical formula for triglyceride — the primary fat in the human body. When you burn fat, or apply oxygen and energy to force it to change shape, it turns into CO2 (carbon dioxide) and H2O (water.) OK, so where do those compounds go?
Remember all of those greenhouse gases that everyone has been talking about? Carbon dioxide is one of them. It's also a common gas in the atmosphere and one that we exhale with every breath. You could argue that the extra carbon dioxide exhaled during weight loss could contribute to climate change. Or you could look at it from a more optimistic standpoint and think of it as providing more of the carbon dioxide that plants need to survive (and in turn convert to oxygen).
As for the water, it's pretty obvious to assume that it is excreted from the body via urine, sweat or other bodily fluids.
So there you have it. Your fat was not really "lost." You just breathed it away with a sigh of relief.
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