A new study has found that an addiction to junk food can be compared to that of drugs like cocaine. How? Basically the pleasure center of the brain gets overloaded when often consuming junk food. Then, in the same way it works with drugs like cocaine or heroin, the pleasure centers “crash”, thus requiring more of the “drug” to achieve the same levels of pleasure.
In the study, published in the journal Nature Neuroscience, three groups of lab rats were studied for 40 days. One of the groups was fed regular rat food. A second was fed bacon, sausage, cheesecake, frosting, and other fattening, high-calorie foods--but only for one hour each day. The third group was allowed to pig out on the unhealthy foods for up to 23 hours a day.
Not surprisingly, the rats that gorged themselves on the human food quickly became obese. But their brains also changed. By monitoring implanted brain electrodes, the researchers found that the rats in the third group gradually developed a tolerance to the pleasure the food gave them and had to eat more to experience a high.
They began to eat compulsively, to the point where they continued to do so in the face of pain. When the researchers applied an electric shock to the rats' feet in the presence of the food, the rats in the first two groups were frightened away from eating. But the obese rats were not. "Their attention was solely focused on consuming food," says Kenny.
In previous studies, rats have exhibited similar brain changes when given unlimited access to cocaine or heroin. And rats have similarly ignored punishment to continue consuming cocaine, the researchers note.
The neurotransmitter dopamine appears to be responsible for the behavior of the overeating rats, according to the study. Dopamine is involved in the brain's pleasure (or reward) centers, and it also plays a role in reinforcing behavior. "It tells the brain something has happened and you should learn from what just happened," says Kenny.
Overeating caused the levels of a certain dopamine receptor in the brains of the obese rats to drop, the study found. In humans, low levels of the same receptors have been associated with drug addiction and obesity.
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joker
almost 2 years ago
A very interesting article, who would've thought the addictive imapct of junk food could be so great. Definitely not surprised by the findings though
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