A Randomized Online Grocery Store Trial to Test a Salient Tiered Food and Beverage Tax in Saudi Arabia

Taxes on sugar-sweetened beverages in Saudi Arabia (SA) and other countries have reduced purchases of these beverages and their associated calories and sugar. However, expanding such taxes to cover a broader range of foods and nutrients may be more effective at improving overall diet quality.

We tested the effectiveness of a comprehensive, salient, tiered, nutrient-based food and beverage (F&B) tax using a fully functional online grocery store. A total of 644 SA shoppers were randomized into 1 of 3 conditions: no-tax (control); the current beverage tax (current tax); or the comprehensive, salient tiered F&B tax (comprehensive tax) targeting all products.

The nutritional quality of the shopping baskets, measured by average Nutri-Score points (ie, base scores used to determine the Nutri-Score grades from A [healthiest] to E [least healthy]), weighted by serving size, did not differ statistically between the control and current beverage tax arms. However, the comprehensive tax led to healthier baskets, improving Nutri-Score points by 0.88 (95% CI -0.07 to 1.83) relative to the control arm and 1.16 points (95% CI 0.21 to 2.11) relative to the current tax arm, which is equivalent to a 3.04% and 4.05% increase, respectively.

These findings suggest that a comprehensive, salient tiered F&B tax has the potential to improve diet quality among SA shoppers.