TOPLINE: 

An analysis of 6 years of Taco Bell drive-through transaction data from 120 locations across the US found that implementing taxes on sugary drinks was not associated with changes in calories from beverages per transaction.

METHODOLOGY: 

• Several US cities imposed small excise taxes on sugary beverages between 2015 and 2018, designed to improve dietary behavior; however, it isn’t clear how these taxes affect calorie intake from beverages purchased in fast-food restaurants.
• Researchers analyzed 6 years of transaction-level sales data (2015-2020) from 120 Taco Bell restaurants in the US: 60 restaurants in five jurisdictions where sugary drink taxes were implemented (Albany, California; Cook County, Illinois; Oakland, California; Philadelphia; and Seattle) and 60 matched comparison restaurants in locations where taxes were never implemented.
• They compared changes in the number of calories per transaction for beverages between the tax and no-tax groups during the baseline period (3-14 months prior to tax implementation) and the follow-up period (3-24 months post-implementation).
• The primary outcome was the difference in the number of beverage calories per transaction from individually purchased drinks and from combo meals for drive-through transactions only. Researchers calculated the figure for unconditional transactions (all transactions, regardless of whether a beverage was purchased) to capture changes in beverage size and decisions not to buy a beverage and for conditional transactions (only transactions that included a beverage purchase).

TAKEAWAY: 

• At baseline, the average number of calories per transaction for individual beverages was 51.1 in the tax group and 42.3 in the no-tax group; for combo meal beverages, it was 119.5 and 115, respectively.
• Implementation of sugary drink taxes was not associated with changes in the number of calories from beverages purchased per conditional or unconditional transaction during follow-up for either individual drinks or combo meal drinks.
• One exception was Oakland, where the average beverage calories from combo meals fell by 16.8 for unconditional transactions relative to the no-tax group. However, the impact on beverage calories from combo meals in Oakland was null for conditional transactions, suggesting that customers shifted to buying combo meals without a drink.

IN PRACTICE: 

“The impact of sugary drink taxes in aggregate, in combination with our evaluation of price changes, suggests that the sizes of sugary drink taxes in the US are too small to change beverage calories purchased in fast food restaurants,” the authors wrote.

SOURCE: 

The study, led by Pasquale E. Rummo, PhD, Department of Population Health, NYU Grossman School of Medicine, New York, was published online on April 2 in PLOS Medicine.

LIMITATIONS: 

A key limitation was the exclusion of beverage calorie data from in-restaurant transactions. Most restaurants (47 out of 60) were located in Cook County, where the tax was repealed after 4 months of implementation. The study lacked demographic information about the individuals who made the transactions. 

DISCLOSURES: 

This study received support from the National Heart, Lung, and Blood Institute of the National Institutes of Health. The authors reported no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.