New York, Oct 26 (IANS) Have you ever wondered why some people just cannot stick to a planned diet while others face no such issues? They may just not be wired for that, suggests a new study that found a link between ability to self-regulate a healthy body weight and individual brain structure.

Dieting success may be easier for some people because they have an improved white matter mechanism connecting the executive control and reward systems in their brain, the study, published in the journal Cognitive Neuroscience, said.

The research involved a group of thirty six chronic dieters, with mean body fat of 29.6 per cent.

Pin-Hao Andy Chen from Dartmouth College in Hanover, New Hampshire, US and colleagues asked them to make simple judgements on images in order to divert their attention from the real aim of the task.

The activity carried out was a food cue reactivity task designed to localise the executive control and reward areas in the brain, using functional magnetic resonance imaging (fMRI).

After localising the executive control and reward areas, the researchers used diffusion tensor imaging (DTI) to identify the white matter track connecting these areas in order to quantify the integrity within this tract.

The functional MRI results demonstrated that dieters showed greater reactivity to food images than control images.

The DTI results further showed that those with lower body fat percentages showed greater white matter integrity between executive control and reward areas of the brain.

"Individuals with reduced integrity may have difficulty in overriding rewarding temptations, leading to a greater chance of becoming obese than those with higher structural integrity," the researchers said.