Now that it's spring, many people are starting to think about how to lose winter weight in time for summer. But once you've finally dropped a few pounds, where does all that excess fat go? Into the air, according to physicist Ruben Meerman.
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Meerman was surprised to learn that many health professionals weren't sure about the mechanisms in how weight loss works. A survey he conducted of 150 Australian doctors, dietitians and personal trainers showed that most thought fat was converted to energy. In 2014, Meerman, along with biochemist Andrew Brown of the University of New South Wales in Australia, published a paper in the journal BMJ explaining why that's false.
In the paper, the team explain that metabolized fat turns into carbon dioxide, water and energy.
According to their reasoning, our lungs are the main excretory organ for weight loss as it releases the carbon dioxide. Water from the metabolized fat is passed through our urine, sweat, tears or other bodily fluids.
Dietitian Duane Mellor, lecturer at Coventry University in the United Kingdom, told the BBC in December 2014, when the paper was published, that this process is similar to how a car burns fuel.
"The atoms left after breaking down fat for energy are like the exhaust fumes," he said.
The study authors estimate that the average 150-pound person loses about 203 grams of carbon each day. However, if you replace one hour of lounging on the couch with jogging, you would lose another 39 grams of carbon, which essentially means exercise does assist with weight loss.
Although it may seem counter intuitive, increasing your intake of healthy fats can help prevent weight gain & help you feel as if you've had enough to eat. Olive oil, coconut oil, avocados, nuts & seeds are examples of healthy fat that can have a beneficial effect on #weightloss pic.twitter.com/H7NznOQ14n
— Lori Shemek, PhD (@LoriShemek) March 23, 2018
"None of this biochemistry is new, but for unknown reasons it seems nobody has thought of performing these calculations before," Meerman and Brown told BBC.
For those who want to drop a few pounds, the authors advise people focus on the "eat less, move more" way of thinking. Losing 1 pound requires burning 3,500 more calories than you've consumed, according to the Mayo Clinic.