“Caffeine, as a powerful stimulant, releases dopamine in the brain, which stimulates the mind and body. This leads to a highly energetic state, which in turn increases impulsivity and reduces self-control. It is,” said lead author Dipayan Biswas, a Frank Harvey endorsed professor of marketing at USF.
“As a result, caffeine intake leads to impulsivity of purchases in terms of a higher number of items purchased and greater spending.”
Experiments included installing an espresso machine at the entrance of a retail chain and home goods store in France and a department store in Spain.
Upon entry, more than 300 shoppers were provided with a complimentary cup—about half of the offered coffee contained about 100 milligrams of caffeine and the other decaf or water. They shared their receipts with the researchers as they left the store. The team found that caffeinated individuals bought a significantly higher number of items and spent more money than those who had decaf or water.
The researchers found that caffeine also affected the types of items they purchased. Caffeinated coffee drinkers buy more non-essentials Compared to other buyers, such as scented candles and fragrances. However, there was minimal difference between the two groups when it came to utilitarian purchases such as kitchen utensils and storage baskets.
They set up a fourth experiment in a lab and got similar results, this time with regard to online shopping. They divided a study pool of 200 business school students between individuals who consumed caffeinated and decaffeinated coffee and asked them which items to buy from a pre-selected list of 66 options.
Those who consumed caffeine chose more items that were considered impulsive shopping, such as a massage, while others chose more practical items, such as a notebook.
“While consuming moderate amounts of caffeine can have positive health benefits, having caffeine while shopping can have unintended consequences,” Biswas said. “That is, consumers trying to control impulsive spending should avoid consuming caffeinated beverages prior to purchase.”