A study, conducted by researchers at the University of Amsterdam, concluded that when people encounter stimuli that they have learned to associate with certain food items, they are likely to choose those products even when they know they are unhealthy.
This pull factor overpowers the provision of information on healthy diets that governments are increasingly disseminating in order to combat the obesity epidemic, psychologists Aukje Verhoeven, Poppy Watson and Sanne de Wit established.
The paper, published yesterday (1 January) in the journal Appetite, details the results of an investigation into the effects of health warnings on food choices. These warnings were given in the presence or absence of food-associated stimuli. The researchers looked at “every kind of stimuli associated with food”, including adverts or the sight or smell of food.
Health warnings rendered ‘ineffective’
It would seem that, when it comes to food choices, overall consumers can resist anything except temptation.
“Health warnings often make people want to choose healthier food products, yet many still end up picking unhealthy food products,” Verhoeven noted. “We suspected this might partly be due to the fact that people learn to associate specific cues in their environment with certain food choices.”
Verhoeven suggested this extends from stimuli such as smell to include visual stimuli such as branding. “For example, eating a cheeseburger regularly occurs in the visual presence of a large logo M. This causes a strong association between the stimulus (the logo) and the rewarding experience of eating a cheeseburger. Simply seeing an M eventually causes us to crave a burger and triggers a learned behaviour to head to a fast-food restaurant. Unhealthy choices are therefore automatically activated by learned associations, making health warnings, which focus on conscious choices, ineffective.”
To test their hypothesis, the researchers used a specific computer task, the Pavlovian-instrumental transfer, in a controlled setting to simulate the learning processes between certain food choices and environmental stimuli in subjects.
“Health warnings for healthy food choices only seem to be effective in an environment where no food cues are present. Whenever stimuli are present which people have come to associate with certain snacks, they choose the accompanying (unhealthy) food product, even when they know it is unhealthy or aren’t really craving that food product. It didn’t matter whether we alerted the subjects before or after they learned the associations with food cues,” Verhoeven added.
Promoting healthy choices
Given the significant impact that stimuli have on food choices, the researchers suggested it is necessary to decrease the level of food-associated stimuli that people – “and children in particular” – are exposed to.
One way to do this would be to decrease the amount of advertising for unhealthy foods, the researchers suggested. While restrictions on marketing unhealthy foods to children have been imposed at a national level by some European countries such as the UK, such restrictions have largely been opposed by food manufacturers.
Food-related stimuli could also potentially be used to promote healthier diets, Verhoeven also stipulated.
“It is worthwhile exposing people to healthy food products together with certain environmental cues more often, for example by showing more adverts for healthy products.
“The environment could also be shaped such that healthy choices are the easiest to make, for instance by placing healthy products at the front in canteens or by replacing chocolate bars with apples and healthy snacks at the cash register. In this way, you give people a gentle push in the right direction.”
Published online ahead of print: DOI: 10.1016/j.appet.2017.10.020
"Failing to pay heed to health warnings in a food-associated environment"
Authors: Aukje A. C. Verhoeven, Poppy Watson, & Sanne de Wit