The researchers from Brunel University, London found the majority of unrestrained eaters preferentially chose an unhealthy snack pack, irrespective of the advertisement while highly restrained eaters who had seen the healthy eating message chose a healthier snack.
"The healthy eating message, when distributed through mass media, resonated with restrained eaters only. Exposure to healthy food adverts provoked restrained eaters into choosing a snack pack; while exposure to other messages results in restrained eaters refusing to take any foods," they write.
"For the majority of participants, there was an increased likelihood that they would choose a snack pack [that is] high in fat, salt and sugar (HFSS) irrespective of advertisements they were exposed to. Therefore, when given an option of a free snack pack, the majority of participants tended to prefer to follow their hedonic food choice.
Despite the overwhelming presence of HFSS foods in media advertising, the researchers say little research has focused on advertising nutritious foods with a healthy eating narrative and how these subsequently impact viewers' eating behaviours.
Emotional eating is defined as overeating in order to relieve negative emotions.
Restrained eating describes the tendency of people to restrict food intake to achieve weight loss or to prevent weight gain.
External eating refers to an increased tendency to eat in response to external cues, such as the sight or smell of food.
Individuals were asked 33 questions to determine eating traits, such as ‘If you walk past the baker do you have a desire to buy something delicious?’ (external); ’If you have put on weight, do you eat less than you usually do?’ (restrained) and ‘Do you have a desire to eat when you are upset?’ (emotional).
Genuine TV adverts used
For the study, 80 male and female participants aged 18 – 24 years old were recruited, most of whom were either staff or students at a London university. Of these, 63 participants fell into the lean category with a healthy body mass index (BMI) and 17 were considered to be overweight.
After determining what kind of eating characteristics individuals had - restrained, emotional or external -, the researchers assigned participants to one of three group. 25 individuals were shown advertisements for foods high in salt, far and sugar (real-life adverts for Cadbury's Dairy Milk and Pringles) while 26 were shown healthy food adverts (Nakd bar and the Organic Food Market). A control group with 29 individuals were shown adverts for non-food items (toilet paper and perfume).
They were then offered a choice between two snack packs, one perceived to be healthy and natural (despite having high glycaemic indices) that contained a banana, an organic granola bar and dried raisins; and one containing five individual chocolates, a pack of ready salted Walker's crisps and a chocolate muffin.
The researchers hypothesised that participants were more likely to choose healthy snacks following the healthy food adverts and to choose unhealthy snacks after exposure to unhealthy food adverts, but this turned out to be only partially the case.
"The message portrayed in the healthy food advertisement appears to resonate with the restrained eater and alters their habitual food choice. The habitual choice of restrained individuals was to decline to take either healthy or HFSS snack pack. The implication of this result would be that the healthy food advertisement stimulates food choice in high restrained individuals and may constitute a net increase in food intake."
They suggest that further research could look at consumers’ willingness to pay, given that the snack packs were offered for free in this study.
“Responsiveness to healthy advertisements in adults: An experiment assessing beyond brand snack selection and the impact of restrained eating”
Available online 19 January 2017, http://dx.doi.org/10.1016/j.appet.2017.01.015
Authors: Terence M. Dovey, Tina Torab, Dorothy Yen et al