Oral Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2024

Mitigating unintended consequences: Evaluating combined sugar and sweetener warning labels on beverage choices in a real-world selection task (#95)

Enola Kay 1 2 , Kerry Ettridge 1 3 , Joanne Dono 1 4 , Caroline Miller 1 3
  1. Health Policy Centre, South Australian Health and Medical Research Institute, Adelaide, Australia
  2. Psychology, College of Education, Psychology, and Social Work, Flinders University, Adelaide, Australia
  3. School of Public Health, University of Adelaide, Adelaide, SA, Australia
  4. School of Psychology, University of Adelaide, Adelaide, SA, Australia

Background: Front-of-pack (FOP) warning labels (WLs) have demonstrated effectiveness for reducing sugar-sweetened beverage (SSB) consumption, but with an unintended consequence of increasing consumption of non-sugar sweetened beverages (NSSBs). A real-stakes experimental study examined the effectiveness of combining sugar and sweetener WLs to reduce SSB consumption and limit NSSB substitution, independently and in conjunction with Australia’s existing Health Star Rating (HSR) system to determine suitability for an Australian context.

Methods: In a local university setting, participants (N=414) accessed an online convenience store app via laptops set up on campus to select one of 10 commercially available beverages (mix of SSBs, 100% fruit juice, NSSBs, water) following an escalating exposure procedure. Drinks were presented in three rounds: 1) without any FOP labelling; 2) with WLs added to sugary drinks or to both sugary drinks and NSSBs (according to allocated labelling condition); and 3) with HSR icons added to all drinks. Participants received their chosen beverage following the completion of a brief questionnaire.

Results: At baseline (Round 1), the most and least popular drink choices were SSBs (42.3%) and water (9.2%). FOPWLs on sugary drinks (Round 2) significantly decreased selection of SSBs (46.5-29.6%; p<.001), and increased NSSB (29.1-40.8%; p<.01) and water choices (8.0-17.4%; p<.01); with water becoming the most popular individual drink choice. Placing FOPWLs on both sugary drinks and NSSBs avoided a significant increase in NSSB choices (36.3-40.3%; p>.05), and significantly increased water selections (10.4-17.4; p<.05), but did not significantly decrease SSB choices (37.8-31.8%; p>.05). The incorporation of HSR icons (Round 3) had little additional effect, but complemented WL effects.

Conclusions: Results demonstrate the potential of FOPWLs for addressing beverage consumption behaviours. The incorporation of sweetener WLs may deter substitution towards NSSBs, whilst still promoting water choices, but may also dilute the impact of the sugary drink WLs.