Why we love junk

Scientists believe they may have cracked the secret of why we all love junk food so much.

The answer, they claim, is in the texture. Certain consistencies, such as those of cream or butter, trigger the pleasure centres in the brain.

The researchers found the oiliness of cream, the thickness of gravy or the grittiness of nuts can all affect how much we crave a particular food.

Doctors at the University of Oxford placed 12 people inside a brain-scanning machine, and fed them different-textured foods through a tube.

The thicker solutions triggered a brain area that overlaps with one activated by taste. Fatty mixtures also fired up a brain region that is activated by pleasure.

The researchers believe humans evolved ways to detect the textures of energy-dense foods, such as fats, so that they could gobble them down in case supplies became scarce.