Many of us might use this long weekend to hit the malls and do a bit of shopping, but you might want to think about what you drink before you go! 

A new study out this week in the Journal of Marketing found that shoppers that drank just one cup of caffeinated coffee right before hitting the shops spent 50% more money and bought 30% more items compared to those that drank a decaf or just water. 

The study was based on a series of experiments where the researchers offered free coffee to shoppers at the entrance of a homeware and department store. 

The 300 people studied were offered a caffeinated espresso, a decaffeinated espresso or some water. 

They were then asked to share their receipts as they left the store. 

The caffeinated shoppers spent an average of $28.91, bought an average of 2.16 items and were more likely to buy non-essential items like candles compared to the decaf shoppers who spend $15/59 and bought 1.45 items. 

In a different experiment, 200 online shoppers were asked to pick from a list of 66 items.  The caffeinated group were more likely to add impulse items like a massager after a coffee whereas the uncaffeinated group made more practical choices like a notebook. 

If you are wanting to save money, it might be worth skipping the coffee shop before heading in to your favourite store! 

Dr Michelle Dickinson joined Francesca Rudkin.

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