Thehigh-calorie foods can be as addictive as tobacco or drugs, according to a study by the Scripps Research Institute (United States) published in the online edition of the journal Nature Neuroscience. The study, conducted with rats, shows that excessive consumption of high-calorie foods cantrigger addiction-like responses in the brain, and that “junk food” can turn rats into compulsive eaters in the laboratory.
The scientists, led by Paul Kenny, measured the rats’ sensitivity to reward experiences. When the researchers regularly offered the rodents a choice of high-calorie foods such as bacon, sausage and chocolate, in addition to their usual healthier but less palatable diet, the animals ate excess calories and quickly gained weight. Also, as they developobesityI knowimpairs chemical balance in reward circuits.
On the other hand, the experiments showed that whenpleasure circuits become less responsive; rats eat more high-calorie and high-fat foods.Similar changes occur in the brains of these animals when they consume cocaine or heroin.
A real addict, be it rat or human,You will also use your drug compulsively, even if it is clearly harmful to your health. To test this, the researchers trained the rats to expect painful electric shocks to the legs when they saw a light signal. Although normal rats stopped eating even the most delicious junk food when the light was turned on, obese rats accustomed to the high calorie diet continued to eat.
The study authors also found lower levels of a specific dopamine receptor in overweight rats, just as they do in drug-addicted humans.
