Study leader Susan E. Swithers, a Purdue University psychology professor, and colleagues used laboratory rats, giving half of the rats high-fat chow and the other half low-fat chow. Half of the rats in each group also were fed Pringles potato chips that are high in fat and calories and the other half in each group were fed high-calorie Pringles chips on some days and low-calorie Pringles Light chips -- made with olestra, a fat substitute with zero calories that passes through the body undigested -- on other days.
The study, published in the journal Behavioral Neuroscience, found the rats on the high-fat diet that ate both types of potato chips consumed more food, gained more weight and developed more fatty tissue than the rats that ate only the high-calorie chips.
In addition, the rats on the high-fat diet didn't lose the extra weight even after the potato chips were removed from their diet.
"Based on this data, a diet that is low in fat and calories might be a better strategy for weight loss than using fat substitutes," Swithers said.