García-Chávez Claudia Gabriela, Barrientos-Gutierrez Tonatiuh, Ng Shu Wen, Rivera Juan A, Colchero M Arantxa
Center for Population Health Research, National Institute of Public Health, Cuernavaca, Mexico.
Carolina Population Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
BMJ Public Health. 2025 May 30;3(1):e001524. doi: 10.1136/bmjph-2024-001524. eCollection 2025.
In January 2014, the Mexican federal government implemented a tax to sugar-sweetened beverages of 1 peso per litre and an 8% tax to non-essential energy-dense foods. Prior studies have evaluated the association of these taxes on household purchases, but none considered the potential heterogeneity of purchases by type of store. We aimed to estimate the impact of the taxes on food and beverage purchases in Mexican households overall and by type of store.
We estimated changes in the quantity purchasesd of taxed and untaxed food and beverages using six rounds of the Mexican National Household Income and Expenditures Survey, which are repeated cross-sectional surveys. To estimate changes in purchases, we used a two-part model, testing for interactions by type of store to assess effect modifications.
During the 4 years after the implementation of the taxes, purchases of non-essential energy-dense foods and sugar-sweetened beverages decreased on average by -7.0% and -4.4%, respectively. There was also a slight decrease in purchases of untaxed foods (-1.7%), while untaxed beverages increased by 10.9%. The largest reductions for taxed foods were found in small neighbourhood stores (-19.0%). We did not observe significant heterogeneity in the remaining types of stores. For SSBs, public markets showed the largest decrease (-22.7%) followed by small neighbourhood stores (-11.4%), while increases were observed in convenience stores (44.8%) and other stores (22.2%). The high increases in convenience and other stores suggest that taxes may not be fully passed on to prices, that promotional pricing was used to offset the tax or that these increases reflect secular trends.
Despite the modest amounts of taxes in Mexico, reductions in purchases were documented 4 years after implementation, emphasising the potential benefits of increasing the taxes. Heterogeneity in purchases by store types suggests the need to analyse differences in the tax pass-through and its mechanisms at the store level.
2014年1月，墨西哥联邦政府对含糖饮料征收每升1比索的税，并对非必需的高能量食品征收8%的税。先前的研究评估了这些税收与家庭购买行为之间的关联，但没有一项研究考虑到不同类型商店购买行为的潜在异质性。我们旨在估计这些税收对墨西哥家庭食品和饮料购买行为的总体影响以及按商店类型划分的影响。
我们使用墨西哥国家家庭收入和支出调查的六轮数据（重复横断面调查），估计了应税和非应税食品及饮料购买量的变化。为了估计购买量的变化，我们使用了一个两部分模型，通过商店类型进行交互作用检验，以评估效应修正。
在税收实施后的4年里，非必需的高能量食品和含糖饮料的购买量平均分别下降了7.0%和4.4%。非应税食品的购买量也略有下降（-1.7%），而非应税饮料则增加了10.9%。应税食品购买量降幅最大的是小型社区商店（-19.0%）。我们在其他类型的商店中未观察到显著的异质性。对于含糖饮料，公共市场的降幅最大（-22.7%），其次是小型社区商店（-11.4%），而便利店（44.8%）和其他商店（22.2%）则出现了增长。便利店和其他商店的大幅增长表明，税收可能没有完全转嫁到价格上，可能采用了促销定价来抵消税收，或者这些增长反映了长期趋势。
尽管墨西哥的税收额度不大，但在实施4年后仍记录到购买量的下降，这凸显了提高税收的潜在益处。不同商店类型的购买行为异质性表明，有必要在商店层面分析税收转嫁及其机制的差异。
