What happens when sugar-sweetened beverage labelling and tax policies are extended to non-sugar sweetened beverages? A national study of Australians’ responses

Warning labels and taxes can effectively contribute to reducing sugar-sweetened beverage (SSB) consumption as part of a comprehensive public health strategy, but may also result in substitution to alternative drinks, including to those with uncertain health effects (e.g., those with non-sugar substitutes). Participants of a nationally representative sample of Australian adults (18 + years) were randomly allocated to a hypothetical warning label ( n = 1,442) or 20% SSB tax ( n = 1,428) policy condition. Each policy was first applied to SSBs alone, then extended to include non-sugar sweetened beverages (NSSBs). Participants reported whether each policy would discourage consumption and indicated likely alternative drinks (NSSBs, 100% juice, low sugar, water). Around half of participants agreed that warning labels (56%) or an SSB tax (51%) would discourage their SSB consumption, with slightly lower agreement when policies were extended to NSSBs (44% for both). Across all scenarios, water was the most common intended alternative (68–70%), followed by 100% juice (53–58%), and NSSBs (43–46%, SSB-only policies). Those who regularly consumed alternative beverages were more likely to indicate they would switch to them in response to SSB policies, with similar patterns observed when policies targeted NSSBs. Overall, SSB labelling and taxes show potential for reducing SSB consumption and encouraging water consumption. However, substitution towards other beverages, such as NSSBs, remains a potential risk for many consumers. Extending beverage policies to incorporate NSSBs may help align consumer responses with public health objectives.