Purpose

The purpose of this study is to investigate how combined nutrition labelling influences consumer attitudes, subjective norms, perceived behavioural control and purchase intention for sugar-sweetened beverages (SSBs).

Design/methodology/approach

This study adopted a mixed method research, quasi-experimental design with 406 valid Taiwanese samples to evaluate the possible effects of combined nutrition labelling on SSB purchase intention; two focus group interviews with four nutritional experts and 12 students were conducted to explain how and why consumers perceived different types of combined nutritional labels.

Findings

Combined labels including sugar type/gram with the guideline daily amounts and traffic light display were perceived by consumers as high-quality and reliable, which improved consumer attitude and SSB purchase intention. Consumers perceived the traffic light display and warning claim as a sugar over-consumption message, which reduced SSB purchase intention through subject norms.

Practical implications

Governments should be aware that concrete nutritional information (NIP) leads to the worst SSB consumption. Moreover, the authors suggest that policymakers emphasise the effectiveness of warning claims on SSB products with “sufficient” sugar information to trigger consumers' concern, remind SSB manufacturers of their moral obligation to consumers.

Originality/value

This study identified that the combined effects of nutritional attributes and parts of meanings might be enhanced, eliminated or even separated from their original meaning. Although the label messages were delivered simultaneously, the consumer's psychological perceptions proved to be more complicated than a single attribute and sequentially affected consumer attitudes, subject norms and SSB purchase intention.