Rats would rather starve than eat healthy food

Adding fuel to the idea that junk food is like crack, scientists at Scripps Florida say rats fed high-calorie junk food became addicted to the food and voluntarily starved when given healthy food instead.

Scripps Florida scientists Paul Kenny and Paul Johnson have said that junk food changed the rats' brain chemistry in the same way that chronic cocaine use alters an addicts brain functions.

In the experiment, one group of rats was given healthy, nutritionally balanced food. A different group was given "unlimited access to the worst stuff Johnson could find at the supermarket including bacon, sausage, cheesecake, pound cake, Ding Dongs and frosting."

The junk food group gained weight and became less active. "More surprisingly, the fat rats exhibited the sort of self-destructive behaviour associated with human junkies. The rats would eat junk food even if they knew doing so would result in a mild but distinctly uncomfortable electrical shock to their feet."

The scientists then replaced the unhealthy food with the healthy diet of the first group of rats, and the fat rats refused to eat at all.

Junk food alters the brain's chemistry by releasing dopamine that would normally be released when having sex, snorting cocaine or eating a rich dessert, say the scientists. The junk food-addicted rats learned that the easiest way to experience pleasure was by eating high-calorie, high-fat food. Kenny and Johnson hope the results of the study can help people learn to deal with food addictions.