Ruopeng An

Background: Smoking and obesity are two of the leading causes of preventable death in developed countries. We conducted a meta-analysis to examine the association between cigarette smoking and abdominal obesity measured by waist-to-hip circumference ratio (WHR). Method: Keyword and reference search were conducted in four electronic bibliographic databases: Cochrane Library, Embase, MEDLINE, and Web of Science. Articles were included based on predefined study selection criteria. Random-effect model was performed to estimate the relationship between cigarette smoking and abdominal obesity. Results: Fifteen studies (116 146 subjects) met the study selection criteria and were included in the meta-analysis. Compared to those who have never smoked, current cigarette smokers who smoke in a regular basis are associated with 0.0113 (95% CI: 0.0081–0.0145, p < 0.001) higher WHR. Publication bias could be present as the sample sizes of individual studies and the effect sizes are negatively correlated (p < 0.01). Conclusions: In this meta-analysis, we found some preliminary evidence that links cigarette smoking to abdominal obesity. This study has important limitations pertained to observational study design, publication bias, and measurement error. Future research on the casual effect of smoking on abdominal obesity is warranted.

Objectives: To examine whether reducing prices for healthy food purchases leads to changes in self-reported measures of food consumption and weight status. Methods: Repeated surveys of about 350,000 HealthyFood participants and nonparticipants. Results: Program participation is associated with more consumption of fruits/vegetables and whole-grain foods and less consumption of high sugar/salt foods, fried foods, processed meats, and fast food. There is no strong evidence that participation reduces obesity. Conclusions: A substantial price intervention might be effective in improving diets.

Objective: To systematically review evidence from field interventions on the effectiveness of monetary subsidies in promoting healthier food purchases and consumption.Design: Keyword and reference searches were conducted in five electronic databases: Cochrane Library, EconLit, MEDLINE, PsycINFO and Web of Science. Studies were included based on the following criteria: (i) intervention: field experiments; (ii) population: adolescents 12–17 years old or adults 18 years and older; (iii) design: randomized controlled trials, cohort studies or pre–post studies; (iv) subsidy: price discounts or vouchers for healthier foods; (v) outcome: food purchases or consumption; (vi) period: 1990–2012; and (vii) language: English. Twenty-four articles on twenty distinct experiments were included with study quality assessed using predefined methodological criteria.Setting: Interventions were conducted in seven countries: the USA (n 14), Canada (n 1), France (n 1), Germany (n 1), Netherlands (n 1), South Africa (n 1) and the UK (n 1). Subsidies applied to different types of foods such as fruits, vegetables and low-fat snacks sold in supermarkets, cafeterias, vending machines, farmers’ markets or restaurants.Subjects: Interventions enrolled various population subgroups such as school/university students, metropolitan transit workers and low-income women.Results: All but one study found subsidies on healthier foods to significantly increase the purchase and consumption of promoted products. Study limitations include small and convenience samples, short intervention and follow-up duration, and lack of cost-effectiveness and overall diet assessment.Conclusions: Subsidizing healthier foods tends to be effective in modifying dietary behaviour. Future studies should examine its long-term effectiveness and cost-effectiveness at the population level and its impact on overall diet intake.

Excessive alcohol use remains an important lifestyle-related contributor to morbidity and mortality in the U.S. and worldwide. It is well documented that drinking patterns differ across racial/ethnic groups, but not how those different consumption patterns would respond to tax changes. Therefore, policy makers are not informed on whether the effects of tax increases on alcohol abuse are shared equally by the whole population, or policies in addition to taxation should be pursued to reach certain sociodemographic groups. To estimate differential demand responses to alcohol excise taxes across racial/ethnic groups in the U.S. Individual data from the Behavioral Risk Factor Surveillance System 1984-2009 waves (N= 3,921,943, 39.3% male; 81.3% White, 7.8% African American, 5.8% Hispanic, 1.9% Asian or Pacific Islander, 1.4% Native American, and 1.8% other race/multi-race) are merged with tax data by residential state and interview month. Dependent variables include consumption of any alcohol and number of drinks consumed per month. Demand responses to alcohol taxes are estimated for each race/ethnicity in separate regressions conditional on individual characteristics, state and time fixed effects, and state-specific secular trends. The null hypothesis on the identical tax effects among all races/ethnicities is strongly rejected (P < 0.0001), although pairwise comparisons using t-test are often not statistically significant due to a lack of precision. Our point estimates suggest that the tax effect on any alcohol consumption is largest among White and smallest among Hispanic. Among existing drinkers, Native American and other race/multi-race are most responsive to tax effects while Hispanic least. For all races/ethnicities, the estimated tax effects on consumption are large and significant among light drinkers (1-40 drinks per month), but shrink substantially for moderate (41-99) and heavy drinkers (≥ 100). Extensive research has been conducted on overall demand responses to alcohol excise taxes, but not on heterogeneity across various racial/ethnic groups. Only one similar prior study exists, but used a much smaller dataset. The authors did not identify differential effects. With this much larger dataset, we found some evidence for different responses across races/ethnicities to alcohol taxes, although we lack precision for individual group estimates. Limitations of our study include the absence of intrastate tax variations, no information on what type of alcohol is consumed, lack of controls for subgroup baseline alcohol consumption rates, and measurement error in self-reported alcohol use data. Tax policies aimed to reduce alcohol-related health and social problems should consider whether they target the most harmful drinking behaviors, affect subgroups in unintended ways, or influence some groups disproportionately. This requires information on heterogeneity across subpopulations. Our results are a first step in this direction and suggest that there exists a differential impact across races/ethnicities, which may further increase health disparities. Tax increases also appear to be less effective among the heaviest consumers who are associated with highest risk. More research, including replications in different settings, is required to obtain better estimates on differential responses to alcohol tax across races/ethnicities. Population heterogeneity is also more complex than our first cut by race/ethnicity and needs more fine-grained analyses and model structures.