Shopping on a full stomach is sensible advice to prevent buying up big on foods that you don’t need. Now scientists have taken this idea further by showing that what a person eats before they shop can influence what they buy.
It is age-old advice that it is best not to grocery shop on an empty stomach if you are trying to eat better and eat less. Taking this advice one step further though and injecting some science into it, researchers from Cornell University asked the question if what a person eats before they shop could influence what they purchased. The research was published in Psychology & Marketing.
In the first study, 120 shoppers were randomly given an apple sample, a biscuit sample or no sample at the start of their shopping trip. The shoppers’ purchases were then scrutinised at the end of their shop. The people given the apple sample ended up buying 28 percent more fruits and vegetables compared to those given the biscuit samples or those given nothing.
The next part of the study moved the research out of the supermarket and into the lab. Volunteers shopped online for their purchases, but just like in the first study, were given an apple or biscuit sample before they did their virtual grocery shop. When presented with 20 sets of choices containing one healthy and one less healthy option, those who received the apple sample were more likely to pick the healthier choice compared to those who ate the biscuit.
The final study gave volunteers a chocolate milk drink which was either labelled as ‘healthy’ or ‘rich and indulgent’ before they did their online shopping. Despite the drinks being the same for everyone regardless what the label stated, those that were primed by the ‘healthy’ label were more likely to choose healthier options when presented with contrasting healthy and less healthy food pairs.
The findings from the three studies illustrate the idea of ‘priming’, where exposure to a stimulus activates a conscious or subconscious mental thought related to it. For example, playing French music in a wine store increases sales of French wine.
What it all means
This was only a small study, but showed some impressive results using a very simple study design. It is a good example of ‘nudge theory’ where a small prod, in this case a healthy snack before shopping, can be enough to push people in the direction they wish to be going. Munching on an apple on the way to the supermarket may be one of the simplest and effective health promotion ideas yet.
Andrew Howie says
Yes. i used to work with a chef at a big hospital who pointed out that hungry staff would serve larger servings on the plating line. Very good observation.
Helen says
I think this is true. If there’s been chocolate and cake at work, I am much more likely to crave more on the way home and stop at the supermarket than if I hadn’t had any.
Troy says
Thanks Tim, nice post on some behavioural aspects of food science.
The health halo tends to get a few people in some real strife when eating out and I know I have been guilty in the past of buying more calorie dense food when I’ve already eaten something that’s generally more processed and refined prior to going shopping or eating out.
I’m sure you’ve read it but in case you haven’t one you’d enjoy is a little gem of a book on this topic called ‘Mindless Eating’ by Brian Wansink. It opened my eyes to some really cool and crazy perceptions we can have about food.
Rohana ariffin says
Sounds like a good advice. I will try next time