Lab rats raised on a diet of junk food appeared to prefer to starve themselves rather than switch over to healthier food, scientists in the United States have found.

Research out of Scripps Florida contends that the high-fat, high-calorie food consumed by the rodents affected their brains in much the same way that cocaine alters human brains.

The Palm Beach Post said on Monday that the conclusions could bolster what was an increasingly popular theory that junk food has addictive characteristics that contribute to the surge in obesity in the United States.

The journal Nature Neuroscience has published the results of the 3-year study.

Rats that consumed cheesecake, icing and other products found at a Florida supermarket not only made the rats fat but triggered behaviors that included a refusal to eat more-nutritious fare, and a refusal to lay off the fattening stuff even when a mild electric shock was administered, Paul Kenny, one of the authors, told the Post. (With Inputs from Agencies)