Startling new research suggests there’s a “switch” in the brain that regulates how your body converts food, be it into energy or store it as fat.
Researchers say that switch may not work in some people with obesity, meaning losing weight is not always as easy as changing your diet.
They believe they’ve discovered a mechanism in the brain that controls the body’s conversion of food into white fat or brown fat in the body.
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The scientists at Monash University's Biomedicine Discovery Institute conducted the study on mice, but evidence suggests it would apply to humans too.
"What our studies have shown is that there is a fundamental mechanism at play that normally ensures that energy expenditure is matched with energy intake,” said Dr Garron Dodd, first author on the study.
“When this is defective, you put on more weight.”
This means that not only do scientists have a clearer understanding of why obesity occurs, but could also help with weight loss.
“Potentially we may be able to rewire this mechanism to promote energy expenditure and weight loss in obese individuals,” said Dr Gordon.
"For a long time, the missing piece to the puzzle was always why this occurs in the body.
"We've shown not only why this occurs but also the fundamental mechanism involved. It's very exciting.”
He did warn however that inhibiting the switch to shed excess fat safely is a “long way off”.