80% of fat may leave the body via the lungs

More than 80% of body fat leaves the body through breathing out, say experts.

Human fat cells store triglyceride, made up of three atoms: carbon, hydrogen and oxygen, so to shed fat, people have to break down the atoms in triglyceride via oxidation. By tracing every atom's pathway out of the body, the team of scientists at the University of New South Wales discovered that when 10kg of fat is oxidised, 8.4kg departs the body via the lungs as carbon dioxide (CO2).The remaining 1.6kg becomes water (H2O).The analysis shows the inhaled oxygen required for this metabolic process weighs nearly three times more than the fat being 'lost'. To completely oxidise 10kg of human fat, 29kg of oxygen must be inhaled, producing a total of 28kg of carbon dioxide and 11kg of water.

At rest, a person who weighs 11 stone (70kg) exhales around 200ml of CO2 by taking 12 breaths a minute, they claim. So by breathing out 17,280 times a day they will lose at least 200g of carbon, with around a third of that weight loss achieved during eight hours of sleep.

Going for a run for an hour would help remove an additional 40g of carbon from the body, the researchers say, raising the total loss by around 20 per cent, to 240g.

Follow NEWS.am Medicine on Facebook and Twitter