A recent scientific study on rats shows that our brains’ wiring is what causes humans to love overeating so darn much. Rats offered a selection of rich, tasty human foods not only became obese, but their brain chemistry changed. The rats needed more food to feel content…and discomfort wouldn’t keep them away from their tasty snacks.

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.

The difference between us and other mammals, of course, is that we have access to a stunning array of unhealthy food, and are bombarded with advertisements trying to get us to eat that food.

Fatty foods may cause cocaine-like addiction [CNN] (Thanks, Kelly!)

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