Mexicans' Consumption of Taxed Sugar-Sweetened Beverages and the Psychosocial Determinants of Consumption in the Context of the 2014 Sugar-Sweetened Beverage Tax - A Mixed Methods Study
Creators: Alvarez Sanchez, Cristina
Publisher: name: Columbia University
Year: 2018
Subjects: Health education
Nutrition
Beverages--Taxation
Soft drinks
Mexicans--Health and hygiene
Public health

description: In Mexico about 73 percent adults and 33 percent children have overweight or obesity; and nearly 14 percent adults are estimated to have Type 2 diabetes, being the principal cause of mortality. Obesity and diabetes rates rose sharply starting in the 1980's and 1990's, coinciding with the globalization processes that Mexico underwent resulting in a higher availability and consumption of energy-dense and nutrient-poor ultra-processed foods. Sugar-sweetened beverages (SSBs), carbonated cola beverages such as Coca-Cola in particular, are widely consumed and well integrated into Mexico's cultural fabric and constitute the major source of added sugars in the Mexican diet. High intake of SSBs is associated with weight gain, type 2 diabetes, coronary heart disease, and metabolic syndrome,
      In 2014, the Mexican government introduced a 1-peso-per-liter (approx. US 8 cents; about 10 percent of the pre-tax price) on industrialized SSBs along with many other public health measures in an attempt to curb rising obesity rates. Two years into the SSB tax, purchases of sugary beverages in stores decreased by 7.6 percent on average. This decrease in purchases is remarkable, nevertheless, based on the existing cross-sectional data, the change cannot be s attributable solely to the effect of the taxation. Moreover, there are many other concurrent factors that might have affected demand and purchases of SSBs: like an 8 percent ad valorem tax imposed on discretionary energy-dense food in 2014, the regulation of foods and beverages in schools, and the regulation of food and beverage marketing on TV targeted to children. 
      Further, it may be plausible for the SSB tax to have exerted effect via other mechanisms, such as increasing awareness of negative health outcomes. There is evidence from other countries that junk food and SSB taxes imposed with public health goals contribute to enhancing people's awareness about the negative health consequences of unhealthy foods. 
      The purpose of this study was to explore what are Mexicans' beliefs, attitudes, social norms, and behaviors in relation to SSBs in the context of the SSB tax, and why and how behaviors have been modified. This purpose was addressed using a sequential explanatory mixed methods design, starting with a quantitative survey with a nationally representative sample, followed by a qualitative study with parents and construction workers. 
      Quantitative study. The first phase of the study consisted of closed-ended questions (designed to ask about awareness of and opinion about the effectiveness of the tax, psychosocial determinants of SSB consumption, and perception of change in SSB consumption since the year the tax was implemented) that were developed and inserted into a new questionnaire of the 2016 National Health and Nutrition Survey (ENSANUT) carried out by the Mexican INSP. The questionnaire was administered face-to-face to 6,650 Mexican adults 20-59 years old, providing a representative sample at the national, urban and rural, and regional levels. The two principal statistical analysis conducted were: (a) Logistic regression, used to evaluate the probability of a person reporting a decrease in SSB consumption, given their awareness of the tax, opinion about its effectiveness, psychosocial (SSB health-related beliefs, self-efficacy, and liking of SSBs) and environmental (availability of potable water) determinants, after controlling for covariates; (b) Multiple linear regression analysis, utilized to examine the association between the same factors and current consumption of taxed SSBs. Results showed that compared with adults not aware, adults who were aware of the SSB tax were more likely (OR=1.30) to report a decrease in SSB consumption (p=.012). In urban areas, adults aware of the tax drank a significantly lower amount of taxed SSBs (-15.7%; p=.023) than those not aware. Self-efficacy and liking of SSBs were significantly associated with a reported decrease in consumption and with current consumption (p