The Impact of the Sweetened Beverages Tax on Their Reformulation in Poland—The Analysis of the Composition of Commercially Available Beverages before and after the Introduction of the Tax (2020 vs. 2021)

The aim of this study was to estimate changes in the composition of carbonated and non-carbonated sugar-sweetened beverages before and after the introduction of the beverage tax in Poland. Based on the labels of 198 drinks, the composition and nutritional values of the drinks were compared. The nonparametric Mann–Whitney test was applied to compare the differences in the sugar and juice content as well as energy value. After the introduction of the tax, the median sugar content in the carbonated beverages decreased from 8.6 g to 6.9 g/100 mL (p = 0.004), while in the non-carbonated beverages, it decreased from 5.5 g to 4.8 g/100 mL (p < 0.001). In the entire beverage group, there was a significant drop in the proportion of beverages that contained >5 g of sugars/100 mL (44.4% in 2021 vs. 70.2% in 2020). The median juice content in the carbonated beverages increased from 1.0% to 3.3% (p = 0.121), but totalled 20.0% for both periods in the non-carbonated beverages. The percentage of beverages with a tax-exempt composition (juice content ≥ 20% and sugar content ≤ 5 g/100 mL) almost tripled. After the introduction of the tax, beneficial changes in the compositions of 62% of the analysed beverages were observed in terms of their sugar and/or juice content.