Effect of health warning labels on motivation towards energy-dense snack foods: Two experimental studies

Is evoking fear effective? Exploratory findings from a randomised experiment on the impacts of health warning labels on sugar-sweetened beverages

OBJECTIVE

Health warning labels (HWL) have been suggested to be effective in reducing consumption of sugar-sweetened beverages (SSB). Yet, the efficacy and acceptability of SSB HWL of different formats (textual/pictorial) and severity remain unclear. This exploratory study aims to examine the extent and mechanism through which HWL of different formats and severity may affect responses towards the HWL and SSB consumption.

DESIGN

Randomised online experiment. Participants were exposed to images of a hypothetical SSB bearing a HWL of one of three conditions: text-only HWL, moderately severe pictorial HWL and highly severe pictorial HWL. They then responded to theory-based affective, cognitive and behavioural measures.

SETTING

Singapore.

PARTICIPANTS

One hundred and twenty-seven young adult consumers from a public university.

RESULTS

Direct effects were found for fear, avoidance, reactance and acceptability of the HWL, but not attitude, intention or motivation to consume less SSB. Pictorial (moderately severe and highly severe) HWL were associated with greater fear, avoidance, and reactance, and lower acceptability than text-only HWL. There was weak evidence that highly severe pictorial HWL resulted in greater reactance than moderately severe pictorial HWL. Fear mediated the effect of HWL of different severity levels on avoidance, reactance, intention and motivation, but not for attitude or acceptability.

CONCLUSIONS

Exploratory findings indicate that although pictorial HWL were less acceptable, they may still be effective in influencing intention and motivation to reduce SSB consumption through the psychological mechanism of fear. Hence, graphic HWL should not be dismissed too quickly when considering strategies for reducing SSB consumption.

Impact of health warning labels and calorie labels on selection and purchasing of alcoholic and non-alcoholic drinks: A randomized controlled trial

AIMS

To estimate the impact on selection and actual purchasing of (a) health warning labels (text-only and image-and-text) on alcoholic drinks and (b) calorie labels on alcoholic and non-alcoholic drinks.

DESIGN

Parallel-groups randomised controlled trial.

SETTING

Drinks were selected in a simulated online supermarket, before being purchased in an actual online supermarket.

PARTICIPANTS

Adults in England and Wales who regularly consumed and purchased beer or wine online (n = 651). Six hundred and eight participants completed the study and were included in the primary analysis.

INTERVENTIONS

Participants were randomized to one of six groups in a between-subjects three [health warning labels (HWLs) (i): image-and-text HWL; (ii) text-only HWL; (iii) no HWL] × 2 (calorie labels: present versus absent) factorial design (n per group 103-113).

MEASUREMENTS

The primary outcome measure was the number of alcohol units selected (with intention to purchase); secondary outcomes included alcohol units purchased and calories selected and purchased. There was no time limit for selection. For purchasing, participants were directed to purchase their drinks immediately (although they were allowed up to 2 weeks to do so).

FINDINGS

There was no evidence of main effects for either (a) HWLs or (b) calorie labels on the number of alcohol units selected (HWLs: F(2,599)  = 0.406, P = 0.666; calorie labels: F(1,599)  = 0.002, P = 0.961). There was also no evidence of an interaction between HWLs and calorie labels, and no evidence of an overall difference on any secondary outcomes. In pre-specified subgroup analyses comparing the 'calorie label only' group (n = 101) with the 'no label' group (n = 104) there was no evidence that calorie labels reduced the number of calories selected (unadjusted means: 1913 calories versus 2203, P = 0.643). Among the 75% of participants who went on to purchase drinks, those in the 'calorie label only' group (n = 74) purchased fewer calories than those in the 'no label' group (n = 79) (unadjusted means: 1532 versus 2090, P = 0.028).

CONCLUSIONS

There was no evidence that health warning labels reduced the number of alcohol units selected or purchased in an online retail context. There was some evidence suggesting that calorie labels on alcoholic and non-alcoholic drinks may reduce calories purchased from both types of drinks.

Positive emotions and their upregulation increase willingness to consume healthy foods

While highly relevant for everyday life, it is unclear whether experiencing incidental positive or negative emotional states, and active emotion regulation, influence the weighting of perceived taste and health in food choices. In Experiment 1, we examined two emotion regulation strategies, reappraisal and distraction, used to decrease negative emotions. Participants were cued to experience or decrease their emotional response for either neutral or negative incidental emotion-inducing images. They subsequently rated their willingness to consume foods, which varied in their taste and health attributes. Mixed-effects model analysis showed that compared to neutral, negative emotions decreased willingness to consume, regardless of perceived taste and health, but neither emotion regulation strategy had a significant effect. Experiment 2 used images inducing incidental positive emotions in combination with three emotion regulation strategies: reappraisal, distraction, and increasing positive emotions. Experiencing positive emotions generally increased willingness to consume, with stronger effects for tasty and healthy foods. Decreasing positive emotions via reappraisal decreased willingness to consume, particularly for healthy foods. Increasing positive emotion intensity further increased willingness to consume, with stronger effects for healthy foods. The results suggest that experiencing positive emotions increases desire particularly strongly for healthy foods, which can additionally be modulated via emotion regulation. This has important implications for designing health-related interventions targeting mood improvement.