Junk food rewires the brain to keep people coming back for more.
Junk food rewires the brain
A new study has revealed how treats such as chocolate bars and crisps trigger the body's reward system and teaches it to prefer them to other foods.
Experts in Germany tracked brain activity in two groups of volunteers who were given yoghurts, with one group given a version that had a higher content of fat and sugar.
After eight weeks, the part of the brain responsible for motivation was more fired up when given the yoghurt with more fat and sugar.
Dr. Marc Tittgemeyer, of the Max Planck Institute for Metabolism Research, explained that junk food forms "new connections" in the brain that are hard to unlearn.
He said: "Our measurements of brain activity showed that the brain rewires itself through the consumption of fatty foods.
"It subconsciously learns to prefer rewarding food.
"Through these changes in the brain, we will unconsciously always prefer foods that contain a lot of fat and sugar."