We talk a lot about dieting and burning off fat, but
we actually have a lot of misconceptions about weight loss. Some people think
fat is converted into energy or heat—a violation of the law of conservation of
mass—while others think that the fat is somehow excreted or even converted to
muscle. I was told early on that you can never lose your fat cells (adipose)
once you gain them...they just shrink if you work it off.
Well, according to Andrew Brown from the University of New South Wales and Australian TV personality (slash former physicist) Ruben Meerman, when you lose weight, you exhale your fat. Their new calculations,
based on existing knowledge about biochemistry, were published in the British
Medical Journal this week.
“There is surprising ignorance and confusion about
the metabolic process of weight loss,” Brown says in a news release. “The
correct answer is that most of the mass is breathed out as carbon dioxide,”
Meerman adds. “It goes into thin air.”
Excess carbs and proteins are converted into
chemical compounds called triglycerides (which consist of carbon, hydrogen, and
oxygen) and then stored in the lipid droplets of fat cells. To lose weight,
you’re attempting to metabolize those triglycerides, and that means unlocking
the carbon that’s stored in your fat cells.
Losing 10 kilograms of human fat requires the
inhalation of 29 kilograms of oxygen, producing 28 kilograms of carbon dioxide
and 11 kilograms of water. That’s the metabolic fate of fat.
Then the duo calculated the proportion of the mass
stored in those 10 kilograms of fat that exits as carbon dioxide and as water
when we lose weight. By tracing the pathway of those atoms out of the body,
they found that 8.4 of those kilograms are exhaled as carbon dioxide. Turns
out, our lungs are the primary excretory organ for weight loss. The remaining
1.6 kilograms becomes water, which is excreted in urine, feces, sweat, breath,
tears, and other bodily fluids.
So, for this upcoming post-holiday season, should we
all just exhale more to shed those extra pounds? No. Breathing more than
required by a person’s metabolic rate leads to hyperventilation, followed by
dizziness, palpitations, and loss of consciousness.
Source: iflscience.com
