Can Your Nose Make You Fat? The answer will surprise you.

As ridiculous as the statement sounds, find out here.

When you lose weight, where does all that fat go? And what does it have to do with my nose? The answer will surprise you.

Turns out, the majority of fat is exhaled.

A research from the University of New South Wales in Australia debunks some of the biggest misconceptions about the fate of fat in a human body. Contrary to popular belief, fat does not simply turn into energy or heat, nor does it break into smaller parts and get excreted.


In reality, what happens is the excess carbohydrates and protein are converted to a type of fat called triglyceride. The triglyceride consists of just three elements:

  • Carbon
  • Hydrogen
  • Oxygen

When people attempt to lose weight, they attempt to metabolize these triglycerides. The triglyceride molecules are broken down by unlocking these elements, through a process called oxidation.

When a triglyceride is oxidized, the process consumes many molecules of oxygen while producing carbon dioxide (CO2) and water (H2O) as waste products.


The researchers found that when 10 kg of fat were oxidized, 8.4 kg were converted and excreted as carbon dioxide (CO2) via the lungs, and 1.6 kg became water (H20).

In order for 10 kg of human fat to be oxidized, the researchers calculated that 29 kg of oxygen must be inhaled. Oxidation then produces a total of 28 kg of CO2 and 11 kg of H20.


This shown that lungs are the main excretory organ for weight loss, with H20 produced by oxidation, leaving the body in urine, feces, and other bodily fluids.

On average, a person weighing 70 kg will take a total of 17,280 breaths during the day which gets rid of at least 200g of carbon. A third of this weight loss occurs during 8 hours of sleep.

This has some important implications.

A growing body of research is finding a link between sleep disorders and weight gain.

In one study published in the International Journal of Obesity, for example, scientists from the University of Helsinki found that among 5,700 middle-aged women, those who struggled with sleep disorders were significantly more likely to struggle with their weight than their peers who got the recommended eight hours a night.


Obstructive sleep apnea is a disorder in which the airway becomes blocked during sleep, interrupting breathing. Someone suffering from sleep apnea can stop breathing during sleep for anywhere from 15 seconds to more than a minute – and it can happen dozens of times in a single night. 

In addition to reducing your sleep quality, it can also contribute to weight gain.


The sleep deprivation caused by sleep apnea adversely affects the body’s metabolism. The metabolism regulates hormones which have a direct impact on our hunger levels.  Some of these hormones are insulin, leptin and ghrelin.

  • Insulin regulates our blood sugar levels. When you don’t get enough sleep, insulin tells your body to slow the release of leptin.
  • Leptin is the hormone that tells you to stop eating, and so when leptin levels are low, a sense of insatiable hunger persists.
  • Even worse, when you are sleep deprived, your ghrelin levels go up. This is the “go” hormone that tells you when to eat.
  • Having higher levels of ghrelin makes you more hungry.
  • These hormonal patterns contribute to obesity and lack of exercise.


This can be a vicious cycle. As explained above, insufficient sleep can lead to weight gain and weight gain can lead to a serious problem like sleep apnea, which in turn causes more sleep deprivation and even more weight problems.

About 70% of people with obstructive sleep apnea are overweight or obese, according to the American Sleep Apnea Association


As ridiculous as the above statement sounds, your nose does indeed have a part to play in weight gain. The nose has an extremely important role in normal breathing. Those with a difficulty with breathing through the nose, are likely to have their sleep interrupted. And as you have just learned, quality sleep has an important role in the proper functioning of your metabolism. Essentially inadequate sleep may predispose you to weighty consequences.

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Wiktoria Banda

Wiktoria is a content writer and illustrator at Shape.
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