Brain circuitry may make it more difficult for obese people to lose weight, researchers have found.

Research has shown that the neurotransmitter Neuropeptide Y (NPY), known for stimulating appetite, also controls whether the body burns or conserves energy.

When people curtail their calorie intake, NPY levels rise, signalling to the body that it is in starvation mode and should conserve energy.

Researchers will now look at how to circumvent or manipulate the NPY circuit to trick the body into losing weight.