Smelling food before eating linked to weight gain

US researchers used mice in a study that found the smell of food could play an important role in how the body processed calories.

Using gene therapy, researchers at the University of California, Berkeley, cut off the sense of smell in a group of obese mice.

The scientists found that mice who were unable to smell lost weight as against those who could.

The team was however surprised to find that the slimmer mice who were unable to smell also ate the same amount of high-calorie food as mice who could. Also, the mice who were able to smell doubled in weight and mice with a boosted sense of smell, meanwhile, had the most weight gain.

According to the team, smelling food could lead the body to store it rather than burning it off.

''This paper is one of the first studies that really shows if we manipulate olfactory inputs we can actually alter how the brain perceives energy balance, and how the brain regulates energy balance,'' said Céline Riera, of Cedars-Sinai Medical Center in Los Angeles, The Independent reported.

Another researcher, Andrew Dillin stated, ''We actually made mice get fat and then blocked their sense of smell, www.express.co.uk reported. And what we found that they had lost weight almost immediately. The weight that they lost wasn't muscle mass, not bone mass, only fat mass.

"Weight gain isn't purely a measure of the calories taken in; it's also related to how those calories are perceived."

The next step in the study was to check whether it correlated with humans and could be key to helping weight loss.

He continued: "If we can validate this in humans, perhaps we can actually make a drug that doesn't interfere with smell but still blocks that metabolic circuitry. That would be amazing."