Understanding heterogeneity in price changes and firm responses to a national unhealthy food tax in Mexico

Machine learning-based non-destructive terahertz detection of seed quality in peanut

Rapid identification of peanut seed quality is crucial for public health. In this study, we present a terahertz wave imaging system using a convolutional neural network (CNN) machine learning approach. Terahertz waves are capable of penetrating the seed shell to identify the quality of peanuts without causing any damage to the seeds. The specificity of seed quality on terahertz wave images is investigated, and the image characteristics of five different qualities are summarized. Terahertz wave images are digitized and used for training and testing of convolutional neural networks, resulting in a high model accuracy of 98.7% in quality identification. The trained THz-CNNs system can accurately identify standard, mildewed, defective, dried and germinated seeds, with an average detection time of 2.2 s. This process does not require any sample preparation steps such as concentration or culture. Our method swiftly and accurately assesses shelled seed quality non-destructively.

Effectiveness of implemented global dietary interventions: a scoping review of fiscal policies

BACKGROUND

Although the World Health Organisation (WHO) has proposed the use of fiscal policies to mitigate consumption externalities such as overweight and obesity-related diseases, very little is known about the impacts of the different types and framing of national and/or regional fiscal policies that have been implemented over the years. There is the need to provide up-to-date evidence on the impact of fiscal policies that have been enacted and implemented across the globe.

METHODS

We conducted a scoping review of all implemented government fiscal policies in the food and drinks sector to identify the different types of fiscal policies that exist and the scope of their impact on consumers as well as the food environment. Electronic databases such as the Web of Science and Google Scholar were used to search for appropriate literature on the topic. A total of 4,191 articles were retrieved and 127 were synthesized and charted for emerging themes.

RESULTS

The results from this review were synthesized in MS Excel following Arksey & O'Malley (2005). Emerging themes were identified across different countries/settings for synthesis. The results confirms that fiscal policies improve consumers' health; increase the prices of foods that are high in fats, sugar, and salt; increase government revenue; and shift consumption and purchases towards healthier and untaxed foods.

CONCLUSION

Governments already have the optimum tool required to effect changes in consumer behaviour and the food environment.

Long-term impact of unhealthy food tax on consumption and the drivers behind: A longitudinal study in Hungary

Several countries have introduced public health product taxes with the objective of reducing the absolute amount of consumption of unhealthy food and tackling obesity. This study aims to estimate the long-term impact of the Hungarian public health product tax introduced in 2011. To achieve this, a unique consumer purchase dataset was analysed to examine daily fast-moving consumer goods purchases from a representative sample of 2,000 households from 2010 to 2018. The results indicate that the tax has been fully reflected in consumer prices. A decline in consumption was observed initially, consistent with previous experiences in Hungary and other countries. However, over time, the data suggests a recovery and even an increase in line with the growth of disposable income. The proportion of taxed products in total fast-moving consumer goods purchases increased from 5.9 % (95 % CI: 5.7 % to 6.0 %) in 2010 to 7.4 % (95 % CI: 7.3 % to 7.6 %) in 2018. Furthermore, the tax has contributed to increased inequality as low-income households spend a higher proportion of their total expenditure on it. Although taxes on unhealthy foods have proven effective in the short-term, they may not be adequate for reducing overall consumption in the long-term, particularly as disposable income increases. In conclusion, implementing complex interventions is necessary to achieve sustainable positive changes in dietary habits.

Promoting Healthier Purchases: Ultraprocessed Food Taxes and Minimally Processed Foods Subsidies for the Low Income

INTRODUCTION

Fiscal policies can shift relative food prices to encourage the purchase and consumption of minimally processed foods while discouraging the purchase and consumption of unhealthy ultraprocessed foods, high in calories and nutrients of concern (sodium, sugar, and saturated fats), especially for low-income households.

METHODS

The 2017-2018 packaged food purchase data among U.S. households were used to derive household income- and composition-specific demand elasticities across 22 food and beverage categories. Policy simulations, conducted in 2022-2023, assessed the impact of national taxes on unhealthy ultraprocessed food and beverage purchases, both separately and alongside subsidies for minimally processed foods and beverages targeted to low-income households. Resultant nutritional implications are reported on the basis of changes in purchased calories and nutrients of concern. In addition, financial implications for both households and the federal government are projected.

RESULTS

A sugar-based tax on sugar-sweetened beverages would lower both volume and calories purchased with the largest impact on low-income households without children. Meanwhile, targeted subsidies would increase fruit, vegetable, and healthier drink purchases without substantially increasing calories. Under tax simulations, low-income households would make larger reductions in their absolute volume and calorie purchases of taxed foods and beverages than their higher-income counterparts, suggesting that these policies, if implemented, could help narrow nutritional disparities.

CONCLUSIONS

Levying national taxes on unhealthy ultraprocessed foods/beverages and offering targeted subsidies for minimally processed foods/beverages could promote healthier food choices among low-income households. Such policies have the potential to benefit low-income households financially and at a relatively low cost for the federal government annually.

Applicability of the Socioecological Model for Understanding and Reducing Consumption of Ultra-Processed Foods in Canada

Ultra-processed foods (UPFs) have become a major contributor to the diets of Canadians, with a recent report from Statistics Canada suggesting Canadians are consuming almost one-half of their calories from UPFs. Research has linked UPF consumption with increased risk for chronic diseases such as cardiovascular disease and type 2 diabetes, among others. This paper sought to investigate the popularity of UPFs, particularly among children and teens, utilizing the socioecological model as a framework to illustrate how influences at multiple levels (i.e., public policy, organizational, community, interpersonal, and individual) have played a role in the proliferation of UPFs. Evidence from previous studies is used to identify how factors at different levels may influence UPF consumption and discuss potential strategies for reducing UPF consumption. To meaningfully reduce UPF consumption among Canadians, all levels should be considered, with the goal of creating a healthier Canadian population.

Simulation models of sugary drink policies: A scoping review

INTRODUCTION

Simulation modeling methods are an increasingly common tool for projecting the potential health effects of policies to decrease sugar-sweetened beverage (SSB) intake. However, it remains unknown which SSB policies are understudied and how simulation modeling methods could be improved. To inform next steps, we conducted a scoping review to characterize the (1) policies considered and (2) major characteristics of SSB simulation models.

METHODS

We systematically searched 7 electronic databases in 2020, updated in 2021. Two investigators independently screened articles to identify peer-reviewed research using simulation modeling to project the impact of SSB policies on health outcomes. One investigator extracted information about policies considered and key characteristics of models from the full text of included articles. Data were analyzed in 2021-22.

RESULTS

Sixty-one articles were included. Of these, 50 simulated at least one tax policy, most often an ad valorem tax (e.g., 20% tax, n = 25) or volumetric tax (e.g., 1 cent-per-fluid-ounce tax, n = 23). Non-tax policies examined included bans on SSB purchases (n = 5), mandatory reformulation (n = 3), warning labels (n = 2), and portion size policies (n = 2). Policies were typically modeled in populations accounting for age and gender or sex attributes. Most studies focused on weight-related outcomes (n = 54), used cohort, lifetable, or microsimulation modeling methods (n = 34), conducted sensitivity or uncertainty analyses (n = 56), and included supplementary materials (n = 54). Few studies included stakeholders at any point in their process (n = 9) or provided replication code/data (n = 8).

DISCUSSION

Most simulation modeling of SSB policies has focused on tax policies and has been limited in its exploration of heterogenous impacts across population groups. Future research would benefit from refined policy and implementation scenario specifications, thorough assessments of the equity impacts of policies using established methods, and standardized reporting to improve transparency and consistency.

Evaluation of Economic and Health Outcomes Associated With Food Taxes and Subsidies: A Systematic Review and Meta-analysis

IMPORTANCE

Fiscal policy is a promising approach to incentivizing better food choices and reducing the burden of chronic disease. To inform guidelines on using fiscal policies, including taxes and subsidies, to promote health, the World Health Organization commissioned a systematic review and meta-analysis of the worldwide literature on the outcomes of such policies for food products.

OBJECTIVE

To assess the outcomes of implemented food taxes and subsidies for prices, sales, consumption, and population-level diet and health.

DATA SOURCES

Eight bibliographic databases were searched for peer-reviewed literature and 14 data sources along with governmental websites were searched for grey literature that were published from database inception through June 1, 2020. There were no language and setting restrictions.

STUDY SELECTION

Only primary studies of implemented food taxes and subsidies were considered for inclusion.

DATA EXTRACTION AND SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed. A 3-level random-effects model was used to conduct a meta-analysis of sales and consumption outcomes of fruit and vegetable subsidies. Other outcomes were analyzed in a narrative synthesis.

MAIN OUTCOMES AND MEASURES

Study estimates in the meta-analysis were combined using a price elasticity measure for sales and consumption outcomes. Heterogeneity was assessed using the I2 statistic and τ2. Studies varied in how diet and health were measured.

RESULTS

A total of 54 articles were included in the systematic review, of which 15 studies were included in the meta-analysis. Most food subsidies targeted fruits and vegetables and populations with low income, whereas the evidence on food taxes was primarily from the nonessential energy-dense food tax in Mexico. Sales of subsidized fruits and vegetables increased significantly, with an estimated price elasticity of demand of -0.59 (95% CI, -1.04 to -0.13 [P = .02]; 95% prediction interval, -2.07 to 0.90; I2 = 92.4% [95% CI, 89.0%-94.8%; P < .001]), suggesting inelastic demand. There was no significant change in the consumption of subsidized fruits and vegetables, with an estimated price elasticity of demand of -0.17 (95% CI, -0.49 to 0.15 [P = .26]; 95% prediction interval, -1.01 to 0.67; I2 = 76.2% [95% CI, 54.3%-87.6%; P < .001]). Food excise taxes were associated with higher prices and reduced sales. Evidence was limited on the differential outcomes of food taxes and subsidies across subpopulations.

CONCLUSIONS AND RELEVANCE

Results of this systematic review and meta-analysis indicated that fruit and vegetable subsidies were associated with a moderate increase in fruit and vegetable sales. Further research is warranted to understand the implications of food taxes and subsidies for population-level consumption, diet, and health outcomes.

Changes in Weight-Related Outcomes Among Adolescents Following Consumer Price Increases of Taxed Sugar-Sweetened Beverages

IMPORTANCE

Following the implementation of a tax on sugar-sweetened beverages (SSBs) in Mexico in 2014, SSB prices increased by about 10% on average, but differently across cities. It remains unclear how observed SSB price changes are associated with adolescent weight-related outcomes.

OBJECTIVE

To compare weight-related outcomes among adolescents living in cities with differential SSB price changes before and after the SSB tax was implemented in Mexico.

DESIGN, SETTING, AND PARTICIPANTS

Associations between differential SSB price changes and changes in weight-related outcomes were examined overall and by sex among 12 654 adolescents aged 10 to 18 years born between 1999 and 2002 living in 39 cities in Mexico. Multivariate regressions with individual fixed effects were applied on longitudinal individual-level yearly clinical data (height and weight) from 2012 to 2017 collected by the Instituto Mexicano del Seguro Social (IMSS) and merged with city-level SSB price data from 2011 to 2016 collected by the National Institute of Statistics and Geography (INEGI). Data were analyzed from July 2018 to July 2021.

EXPOSURES

Yearly city-level changes in SSB prices between 2011 and 2016.

MAIN OUTCOMES AND MEASURES

Age- and sex-specific body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) percentile and indicator for overweight or obesity if BMI was at or above the 85th percentile.

RESULTS

Before 2014, 46% of 12 654 adolescents (6850 girls and 5804 boys) included in this study had obesity or overweight. The mean (SD) age was 11.38 (1.08) years. Among girls, a 10% SSB price increase was associated with a 1.3 percentage point absolute decrease (95% CI, -2.19 to -0.36; P = .008) or a 3% relative decrease in overweight or obesity prevalence within 2 years of a price change. For girls with BMI at or above the 75th percentile pretax, this price increase was associated with a 0.59 lower BMI percentile (95% CI, -1.08 to -0.10; P = .02) or a 0.67% relative decrease. Improved outcomes for girls were observed in cities where price increases were greater than 10% after the tax. No such associations were observed for boys.

CONCLUSIONS AND RELEVANCE

In this study, increased SSB prices were associated with decreased overweight or obesity prevalence among girls but not among boys. Improvements in outcomes were small, and mostly observed for girls with heavier weight and in cities where price increases after the tax were greater than 10%.

Associations of a National Tax on Non-Essential High Calorie Foods with Changes in Consumer Prices

Several governments are considering taxes on non-essential energy-dense, high calorie foods (NEDF) to increase their prices and thereby encourage better diet and health. Alongside a tax on sugary drinks in January 2014, Mexico implemented such a tax: an 8 percent ad-valorem tax on NEDF, defined as those with energy density equal or larger than 275kcal/100g. We study the changes in the prices of taxed and tax-exempt foods following this tax both on average and by tax-eligible foods across store types and cities, using monthly price data between 2012 and 2016. We compare within-product price changes before and after the tax adjusting for product fixed effects, seasonality, and trends, and find that prices of taxed foods increased by 4.8 % on average, but differentially across foods. Prices of candies, cookies and packaged pastries increased by eight or more percent post-tax (vs pre-tax); prices of cakes, and savory snacks increased by less. Prices of fresh pastry and ready-to-eat cereal increased, but only in 2014. Prices of chocolate and pizza did not increase after the tax. For tax-exempt foods, no significant price changes were observed. Variability in price changes for taxed foods were observed by cities as well as by stores: increases were larger in supermarkets compared to smaller grocery stores on average and for most foods. Differences in how prices changed across foods, cities and stores have implications for who is likely to be affected by the tax and how tax effects on diet may vary due to the differential tax pass-through in addition to a heterogenous demand response to changed prices.

In search of an appropriate mix of taxes and subsidies on nutrients and food: A modelling study of the effectiveness on health-related consumption and mortality

Taxes and subsidies on foods and nutrients have the potential to promote healthier diets and thereby reduce mortality. In this study, we examine the effects of such policy instruments on Swedish public health. Specifically, we estimate the effects of food and nutrient taxes and subsidies on mortality averted and postponed in Sweden, using both demand system estimations and simulation models. We evaluate different Value Added Tax (VAT) reforms. The VAT is raised on food products that are particularly rich in saturated fat or salt and lowered on fruit and vegetables. Our models predict that an increase in the current VAT of 12% on food, to 25% VAT on products rich in saturated fat plus a 0% VAT on fruits and vegetables would result in almost 1100 deaths (95% CI: -832; -1363) averted or postponed in a year in Sweden, while the combination of a 34.4% VAT on products rich in saturated fat and a -10.4% VAT (i.e. a subsidy) on fruits and vegetables would result in almost 2100 (95% CI: -1572; -2311) deaths averted or postponed corresponding to a 4.8% reduction in diet-related annual death. Most of the deaths averted or delayed from this reform would be deaths from coronary heart disease (-1,148, 95% CI: -728; -1586), followed by stroke -641 (95% CI: -408; -887) and diet-related cancer deaths (-288, 95% CI: -11; -435). We find that health-related food taxes and subsidies improve dietary habits as well as reduce the mortality of the Swedish population. However, the effect of these reforms on different socioeconomic classes and which reforms provide the best value for money, i.e., cost-effectiveness of these reforms needs to be established first before implementation.

Evidence of a health risk 'signalling effect' following the introduction of a sugar-sweetened beverage tax

Consuming sugar-sweetened beverages (SSBs) has been associated with increased rates of obesity and type 2 diabetes, making SSBs an increasingly popular target for taxation. In addition to changing prices, the introduction of an SSB tax may convey information about the health risks of SSBs (a signalling effect). If SSB taxation operates in part by producing a health risk signal, there may be important opportunities to amplify this effect. Our aim was to assess whether there is evidence of a risk signalling effect following the introduction of the Barbados SSB tax. We used process tracing to assess the existence of a signalling effect around sodas and sugar-sweetened juices (juice drinks). We used three data sources: 611 archived transcripts of local television news, 30 interviews with members of the public, and electronic point of sales data (46 months) from a major grocery store chain. We used directed content analysis to assess the qualitative data and an interrupted time series analysis to assess the quantitative data. We found evidence consistent with a risk signalling effect following the introduction of the SSB tax for sodas but not for juice drinks. Consistent with risk signalling theory, the findings suggest that consumers were aware of the tax, believed in a health rationale for the tax, understood that sodas were taxed and perceived that sodas and juice drinks were unhealthy. However consumers appear not to have understood that juice drinks were taxed, potentially reducing tax effectiveness from a health perspective. In addition, the tax may have incentivised companies to increase advertising around juice drinks (undermining any signalling effect) and to introduce low-cost SSB product lines. Policymakers can maximize the impact of risk signals by being clear about the definition of taxed SSBs, emphasizing the health rationale for introducing such a policy, and introducing co-interventions (e.g. marketing restrictions) that reduce opportunities for industry countersignals. These actions may amplify the impact of an SSB tax.