U. study says foods curtail shopping impulses

If you want to avoid an expensive Black Friday shopping spree, you might want to consider scarfing down a heaping helping of turkey and mashed potatoes.

Just in time for the holiday shopping season, two University of Utah researchers have conducted a study that shows some traditional holiday foods enhance the levels of a specific neurotransmitter that can reduce a person's level of impulsive shopping.

The research suggests that eating a traditional Thanksgiving dinner with turkey and mashed potatoes makes consumers less likely to buy on impulse, which might affect the outcome of their shopping on Black Friday, historically one of the busiest retail shopping days of the year.

"We were trying to find out how different types of food can influence subsequent preferences (and) choices," Arul Mishra, study co-author and assistant professor of marketing at the David Eccles School of Business, told the Deseret News.

"We realized that if people had food which was high in tryptophan content, it increases the level of serotonin … and that reduces impulsive responses."

"We Are What We Consume: The Influence of Food Consumption on Impulsive Choice" is expected to be published sometime next year in the Journal of Marketing Research, according to Himanshu Mishra, study co-author, assistant professor of marketing at the University of Utah and Arul's husband.

Arul Mishra said foods rich in carbohydrates have the potential to hike the amount of serotonin in the brain, which could lower a person's willingness to purchase discounted or sale items on a whim.

"Black Friday sales gave us a very good context to (conduct) this research (in a realistic circumstance)," she said.

The study was conducted in 2007 and 2008 with 125 Salt Lake-area participants surveyed on consecutive Thanksgiving holidays using an online questionnaire.

"We found that participants who had consumed a traditional Thanksgiving dinner with turkey displayed less willingness to buy deeply discounted products compared to those who did not consume a traditional dinner," Himanshu Mishra said in a news release about the study.

The combination of tryptophan-rich foods like turkey and carbohydrates like mashed potatoes increases levels of serotonin, a chemical produced in the brain that affects many functions in the central nervous system, including mood, appetite, sleep and some cognition.