The impact of price and nutrition labelling on sugary drink purchases: Results from an experimental marketplace study

To examine the effect of front-of-package (FOP) nutrition labelling and sugary drink taxation on consumer beverage purchases. A total of 675 respondents aged 16 years and older participated in an experimental marketplace study using a 4 × 5 within-between group design. Participants were randomised to one of four labelling conditions (no label; star rating; high sugar symbol; health warning) and completed five within-subject purchase tasks. Beverage prices in each task corresponded to ‘tax’ conditions: 0%, 10%, 20%, 30% and a variable tax proportional to free sugar level. In each task, participants selected from 20 commercially available beverages; upon conclusion, one of five selections was randomly chosen for purchase. As price increased, participants were significantly less likely to select a sugary drink, and selected drinks with fewer calories and less free sugar (p