People tend to spend crisp, new paper money before old, dirty and crumpled bills, Canadian researchers said in studies published Wednesday.

Further, the majority of people will hide their "dirty" money and use fresh bills to impress someone else, the study published in the Journal of Consumer Research found.

Professor Theodore Noseworthy of the University of Guelph, northwest of Toronto, and Professor Fabrizio Di Muro of the University of Winnipeg in Manitoba conducted the overall study in five phases, in which subjects were either given well-worn bills or new ones with instructions to go shopping.

Observers noted the subjects were more likely to spend more of their new-looking currency, even if it meant using four fresh $5 bills rather than one crumpled $20 bill.

"It's the 'ick' factor," Noseworthy said. "The idea of touching something that others also handled: People want to rid themselves of worn currency because they are disgusted by the contamination from others."

The professor said the studies showed a curious consumer association between products and what's used to acquire them.

"We tend to regard currency as a means to consumption and not a product itself," he said. "In other words, it should not matter if it's dirty or worn because it has the same value regardless."