Averting obesity and type 2 diabetes in India through sugar-sweetened beverage taxation: an economic-epidemiologic modeling study

Ending SNAP subsidies for sugar-sweetened beverages could reduce obesity and type 2 diabetes

To reduce obesity and type 2 diabetes rates, lawmakers have proposed modifying Supplemental Nutrition Assistance Program (SNAP) benefits to encourage healthier food choices. We examined the impact of two proposed policies: a ban on using SNAP dollars to buy sugar-sweetened beverages; and a subsidy in which for every SNAP dollar spent on fruit and vegetables, thirty cents is credited back to participants' SNAP benefit cards. We used nationally representative data and models describing obesity, type 2 diabetes, and determinants of food consumption among a sample of over 19,000 SNAP participants. We found that a ban on SNAP purchases of sugar-sweetened beverages would be expected to significantly reduce obesity prevalence and type 2 diabetes incidence, particularly among adults ages 18-65 and some racial and ethnic minorities. The subsidy policy would not be expected to have a significant effect on obesity and type 2 diabetes, given available data. Such a subsidy could, however, more than double the proportion of SNAP participants who meet federal vegetable and fruit consumption guidelines.

Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of type 2 diabetes: systematic review, meta-analysis, and estimation of population attributable fraction

OBJECTIVES

To examine the prospective associations between consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice with type 2 diabetes before and after adjustment for adiposity, and to estimate the population attributable fraction for type 2 diabetes from consumption of sugar sweetened beverages in the United States and United Kingdom.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES AND ELIGIBILITY

PubMed, Embase, Ovid, and Web of Knowledge for prospective studies of adults without diabetes, published until February 2014. The population attributable fraction was estimated in national surveys in the USA, 2009-10 (n = 4729 representing 189.1 million adults without diabetes) and the UK, 2008-12 (n = 1932 representing 44.7 million).

SYNTHESIS METHODS

Random effects meta-analysis and survey analysis for population attributable fraction associated with consumption of sugar sweetened beverages.

RESULTS

Prespecified information was extracted from 17 cohorts (38,253 cases/10,126,754 person years). Higher consumption of sugar sweetened beverages was associated with a greater incidence of type 2 diabetes, by 18% per one serving/day (95% confidence interval 9% to 28%, I(2) for heterogeneity = 89%) and 13% (6% to 21%, I(2) = 79%) before and after adjustment for adiposity; for artificially sweetened beverages, 25% (18% to 33%, I(2) = 70%) and 8% (2% to 15%, I(2) = 64%); and for fruit juice, 5% (-1% to 11%, I(2) = 58%) and 7% (1% to 14%, I(2) = 51%). Potential sources of heterogeneity or bias were not evident for sugar sweetened beverages. For artificially sweetened beverages, publication bias and residual confounding were indicated. For fruit juice the finding was non-significant in studies ascertaining type 2 diabetes objectively (P for heterogeneity = 0.008). Under specified assumptions for population attributable fraction, of 20.9 million events of type 2 diabetes predicted to occur over 10 years in the USA (absolute event rate 11.0%), 1.8 million would be attributable to consumption of sugar sweetened beverages (population attributable fraction 8.7%, 95% confidence interval 3.9% to 12.9%); and of 2.6 million events in the UK (absolute event rate 5.8%), 79,000 would be attributable to consumption of sugar sweetened beverages (population attributable fraction 3.6%, 1.7% to 5.6%).

CONCLUSIONS

Habitual consumption of sugar sweetened beverages was associated with a greater incidence of type 2 diabetes, independently of adiposity. Although artificially sweetened beverages and fruit juice also showed positive associations with incidence of type 2 diabetes, the findings were likely to involve bias. None the less, both artificially sweetened beverages and fruit juice were unlikely to be healthy alternatives to sugar sweetened beverages for the prevention of type 2 diabetes. Under assumption of causality, consumption of sugar sweetened beverages over years may be related to a substantial number of cases of new onset diabetes.

Effects of Health-Related Food Taxes and Subsidies on Mortality from Diet-Related Disease in New Zealand: An Econometric-Epidemiologic Modelling Study

BACKGROUND

Health-related food taxes and subsidies may promote healthier diets and reduce mortality. Our aim was to estimate the effects of health-related food taxes and subsidies on deaths prevented or postponed (DPP) in New Zealand.

METHODS

A macrosimulation model based on household expenditure data, demand elasticities and population impact fractions for 18 diet-related diseases was used to estimate effects of five tax and subsidy regimens. We used price elasticity values for 24 major commonly consumed food groups in New Zealand, and food expenditure data from national Household Economic Surveys. Changes in mortality from cardiovascular disease, cancer, diabetes and other diet-related diseases were estimated.

FINDINGS

A 20% subsidy on fruit and vegetables would result in 560 (95% uncertainty interval, 400 to 700) DPP each year (1.9% annual all-cause mortality). A 20% tax on major dietary sources of saturated fat would result in 1,500 (950 to 2,100) DPP (5.0%), and a 20% tax on major dietary sources of sodium would result in 2,000 (1300 to 2,700) DPP (6.8%). Combining taxes on saturated fat and sodium with a fruit and vegetable subsidy would result in 2,400 (1,800 to 3,000) DPP (8.1% mortality annually). A tax on major dietary sources of greenhouse gas emissions would generate 1,200 (750 to 1,700) DPP annually (4.0%). Effects were similar or greater for Maori and low-income households in relative terms.

CONCLUSIONS

Health-related food taxes and subsidies could improve diets and reduce mortality from diet-related disease in New Zealand. Our study adds to the growing evidence base suggesting food pricing policies should improve population health and reduce inequalities, but there is still much work to be done to improve estimation of health impacts.

Searching for Public Health Law's Sweet Spot: The Regulation of Sugar-Sweetened Beverages

David Studdert and colleagues explore how to balance public health, individual freedom, and good government when it comes to sugar-sweetened drinks.

How Has the Age-Related Process of Overweight or Obesity Development Changed over Time? Co-ordinated Analyses of Individual Participant Data from Five United Kingdom Birth Cohorts

BACKGROUND

There is a paucity of information on secular trends in the age-related process by which people develop overweight or obesity. Utilizing longitudinal data in the United Kingdom birth cohort studies, we investigated shifts over the past nearly 70 years in the distribution of body mass index (BMI) and development of overweight or obesity across childhood and adulthood.

METHODS AND FINDINGS

The sample comprised 56,632 participants with 273,843 BMI observations in the 1946 Medical Research Council National Survey of Health and Development (NSHD; ages 2-64 years), 1958 National Child Development Study (NCDS; 7-50), 1970 British Cohort Study (BCS; 10-42), 1991 Avon Longitudinal Study of Parents and Children (ALSPAC; 7-18), or 2001 Millennium Cohort Study (MCS; 3-11). Growth references showed a secular trend toward positive skewing of the BMI distribution at younger ages. During childhood, the 50th centiles for all studies lay in the middle of the International Obesity Task Force normal weight range, but during adulthood, the age when a 50th centile first entered the overweight range (i.e., 25-29.9 kg/m2) decreased across NSHD, NCDS, and BCS from 41 to 33 to 30 years in males and 48 to 44 to 41 years in females. Trajectories of overweight or obesity showed that more recently born cohorts developed greater probabilities of overweight or obesity at younger ages. Overweight or obesity became more probable in NCDS than NSHD in early adulthood, but more probable in BCS than NCDS and NSHD in adolescence, for example. By age 10 years, the estimated probabilities of overweight or obesity in cohorts born after the 1980s were 2-3 times greater than those born before the 1980s (e.g., 0.229 [95% CI 0.219-0.240] in MCS males; 0.071 [0.065-0.078] in NSHD males). It was not possible to (1) model separate trajectories for overweight and obesity, because there were few obesity cases at young ages in the earliest-born cohorts, or (2) consider ethnic minority groups. The end date for analyses was August 2014.

CONCLUSIONS

Our results demonstrate how younger generations are likely to accumulate greater exposure to overweight or obesity throughout their lives and, thus, increased risk for chronic health conditions such as coronary heart disease and type 2 diabetes mellitus. In the absence of effective intervention, overweight and obesity will have severe public health consequences in decades to come.

Price promotions on healthier compared with less healthy foods: a hierarchical regression analysis of the impact on sales and social patterning of responses to promotions in Great Britain

BACKGROUND

There is a growing concern, but limited evidence, that price promotions contribute to a poor diet and the social patterning of diet-related disease.

OBJECTIVE

We examined the following questions: 1) Are less-healthy foods more likely to be promoted than healthier foods? 2) Are consumers more responsive to promotions on less-healthy products? 3) Are there socioeconomic differences in food purchases in response to price promotions?

DESIGN

With the use of hierarchical regression, we analyzed data on purchases of 11,323 products within 135 food and beverage categories from 26,986 households in Great Britain during 2010. Major supermarkets operated the same price promotions in all branches. The number of stores that offered price promotions on each product for each week was used to measure the frequency of price promotions. We assessed the healthiness of each product by using a nutrient profiling (NP) model.

RESULTS

A total of 6788 products (60%) were in healthier categories and 4535 products (40%) were in less-healthy categories. There was no significant gap in the frequency of promotion by the healthiness of products neither within nor between categories. However, after we controlled for the reference price, price discount rate, and brand-specific effects, the sales uplift arising from price promotions was larger in less-healthy than in healthier categories; a 1-SD point increase in the category mean NP score, implying the category becomes less healthy, was associated with an additional 7.7-percentage point increase in sales (from 27.3% to 35.0%; P < 0.01). The magnitude of the sales uplift from promotions was larger for higher-socioeconomic status (SES) groups than for lower ones (34.6% for the high-SES group, 28.1% for the middle-SES group, and 23.1% for the low-SES group). Finally, there was no significant SES gap in the absolute volume of purchases of less-healthy foods made on promotion.

CONCLUSION

Attempts to limit promotions on less-healthy foods could improve the population diet but would be unlikely to reduce health inequalities arising from poorer diets in low-socioeconomic groups.

Improving health and well-being independently of GDP: dividends of greener and prosocial economies

Increases in gross domestic product (GDP) beyond a threshold of basic needs do not lead to further increases in well-being. An explanation is that material consumption (MC) also results in negative health externalities. We assess how these externalities influence six factors critical for well-being: (i) healthy food; (ii) active body; (iii) healthy mind; (iv) community links; (v) contact with nature; and (vi) attachment to possessions. If environmentally sustainable consumption (ESC) were increasingly substituted for MC, thus improving well-being and stocks of natural and social capital, and sustainable behaviours involving non-material consumption (SBs-NMC) became more prevalent, then well-being would increase regardless of levels of GDP. In the UK, the individualised annual health costs of negative consumption externalities (NCEs) currently amount to £62 billion for the National Health Service, and £184 billion for the economy (for mental ill-health, dementia, obesity, physical inactivity, diabetes, loneliness and cardiovascular disease). A dividend is available if substitution by ESC and SBs-NMC could limit the prevalence of these conditions.

Estimating the effects of a calorie-based sugar-sweetened beverage tax on weight and obesity in New York City adults using dynamic loss models

PURPOSE

Sugar-sweetened beverages (SSBs) contribute to weight gain and increase the risk of obesity. In this article, we determine the effects of an innovative SSB tax on weight and obesity in New York City adults.

METHODS

Dynamic weight loss models were used to estimate the effects of an expected 5800-calorie reduction resulting from an SSB tax on weight and obesity. Baseline data were derived from the New York City Community Health Survey. One, five, and 10-year simulations of weight loss were performed.

RESULTS

Calorie reductions resulted in a per-person weight loss of 0.46 kg in year 1 and 0.92 kg in year 10. A total of 5,531,059 kg was expected to be lost over 10 years when weighted to the full New York City adult population. Approximately 50% of overall bodyweight loss occurred within the first year, and 95% within 5 years. Results showed consistent but nonsignificant decreases in obesity prevalence.

CONCLUSIONS

SSB taxes may be viable strategies to reduce obesity when combined with other interventions to maximize effects in the population.

Opportunities for intervention strategies for weight management: global actions on fluid intake patterns

Water is an essential nutrient for all physiological functions and particularly important for thermoregulation. About 60% of our body weight is made of water. Under standard conditions (18-20 °C and moderate activity), water balance is regulated within 0.2 % of body weight over a 24-hour period. Water requirement varies between individuals and according to environmental conditions. Concerning considerations related to obesity, the health impact of fluid intake is commonly overlooked. Fluid intake advices are missing in most of food pyramids offered to the public, and water requirements and hydration challenges remain often neglected. The purpose of this paper is to emphasize and discuss the role of water consumption in the context of other important public health measures for weight management. Attention will be focused on fluid intake patterns and hydration-related questions in the context of global interventions and/or physical activity programs settled in weight management protocols.

Sugar intake, obesity, and diabetes in India

Sugar and sweet consumption have been popular and intrinsic to Indian culture, traditions, and religion from ancient times. In this article, we review the data showing increasing sugar consumption in India, including traditional sources (jaggery and khandsari) and from sugar-sweetened beverages (SSBs). Along with decreasing physical activity, this increasing trend of per capita sugar consumption assumes significance in view of the high tendency for Indians to develop insulin resistance, abdominal adiposity, and hepatic steatosis, and the increasing "epidemic" of type 2 diabetes (T2DM) and cardiovascular diseases. Importantly, there are preliminary data to show that incidence of obesity and T2DM could be decreased by increasing taxation on SSBs. Other prevention strategies, encompassing multiple stakeholders (government, industry, and consumers), should target on decreasing sugar consumption in the Indian population. In this context, dietary guidelines for Indians show that sugar consumption should be less than 10% of total daily energy intake, but it is suggested that this limit be decreased.

Reducing added sugars in the food supply through a cap-and-trade approach

OBJECTIVES

We estimated the effect of a simulated cap-and-trade policy to reduce added sugar in the food supply.

METHODS

Using nationally representative data on added-sugar content and consumption, we constructed a mathematical model of a cap-and-trade policy and compared its health implications to those of proposals to tax sugar sweetened beverages or added sugars.

RESULTS

Capping added-sugar emissions into the food supply by food manufacturers at a rate of 1% per year would be expected to reduce the prevalence of obesity by 1.7 percentage points (95% confidence interval [CI] = 0.9, 2.4; a 4.6% decline) and the incidence of type 2 diabetes by 21.7 cases per 100 000 people (95% CI = 12.9, 30.6; a 4.2% decline) over 20 years, averting approximately $9.7 billion in health care spending. Racial and ethnic minorities would be expected to experience the largest declines. By comparison, equivalent price penalties through excise taxes would be expected to generate smaller health benefits.

CONCLUSIONS

A cap-and-trade policy to reduce added-sugar intake may reduce obesity and type 2 diabetes to a greater extent than currently-proposed excise taxes.

Diabetes in South Asians

Economic, dietary and other lifestyle transitions have been occurring rapidly in most South Asian countries, making their populations more vulnerable to developing Type 2 diabetes and cardiovascular diseases. Recent data show an increasing prevalence of Type 2 diabetes in urban areas as well as in semi-urban and rural areas, inclusive of people belonging to middle and low socio-economic strata. Prime determinants for Type 2 diabetes in South Asians include physical inactivity, imbalanced diets, abdominal obesity, excess hepatic fat and, possibly, adverse perinatal and early life nutrition and intra-country migration. It is reported that Type 2 diabetes affects South Asians a decade earlier and some complications, for example nephropathy, are more prevalent and progressive than in other races. Further, prevalence of pre-diabetes is high, and so is conversion to diabetes, while more than 50% of those who are affected remain undiagnosed. Attitudes, cultural differences and religious and social beliefs pose barriers in effective prevention and management of Type 2 diabetes in South Asians. Inadequate resources, insufficient healthcare budgets, lack of medical reimbursement and socio-economic factors contribute to the cost of diabetes management. The challenge is to develop new translational strategies, which are pragmatic, cost-effective and scalable and can be adopted by the South Asian countries with limited resources. The key areas that need focus are: generation of awareness, prioritizing health care for vulnerable subgroups (children, women, pregnant women and the underprivileged), screening of high-risk groups, maximum coverage of the population with essential medicines, and strengthening primary care. An effective national diabetes control programme in each South Asian country should be formulated, with these issues in mind.

The potential impact of a 20% tax on sugar-sweetened beverages on obesity in South African adults: a mathematical model

Background/Objectives

The prevalence of obesity in South Africa has risen sharply, as has the consumption of sugar-sweetened beverages (SSBs). Research shows that consumption of SSBs leads to weight gain in both adults and children, and reducing SSBs will significantly impact the prevalence of obesity and its related diseases. We estimated the effect of a 20% tax on SSBs on the prevalence of and obesity among adults in South Africa.

Methods

A mathematical simulation model was constructed to estimate the effect of a 20% SSB tax on the prevalence of obesity. We used consumption data from the 2012 SA National Health and Nutrition Examination Survey and a previous meta-analysis of studies on own- and cross-price elasticities of SSBs to estimate the shift in daily energy consumption expected of increased prices of SSBs, and energy balance equations to estimate shifts in body mass index. The population distribution of BMI by age and sex was modelled by fitting measured data from the SA National Income Dynamics Survey 2012 to the lognormal distribution and shifting the mean values. Uncertainty was assessed with Monte Carlo simulations.

Results

A 20% tax is predicted to reduce energy intake by about 36kJ per day (95% CI: 9-68kJ). Obesity is projected to reduce by 3.8% (95% CI: 0.6%–7.1%) in men and 2.4% (95% CI: 0.4%–4.4%) in women. The number of obese adults would decrease by over 220 000 (95% CI: 24 197–411 759).

Conclusions

Taxing SSBs could impact the burden of obesity in South Africa particularly in young adults, as one component of a multi-faceted effort to prevent obesity.

The transitional dynamics of caloric ecosystems: changes in the food supply around the world

Changes to the global food supply have been characterized by greater availability of edible oils, sweeteners, and meats-a profound "nutrition transition" associated with rising obesity, type 2 diabetes, and cardiovascular disease. Through an analysis of three longitudinal databases of food supply, sales and economics across the period 1961-2010, we observed that the change in global food supply has been characterized by a dramatic rise in pig meat consumption in China and poultry consumption in North America. These changes have not been experienced by all rapidly-developing countries, and are not well explained by changes in income. The changes in food supply include divergence among otherwise similar neighboring countries, suggesting that the changes in food supply are not an inevitable result of economic development. Furthermore, we observed that the nutrition transition does not merely involve an adoption of "Western" diets universally, but can also include an increase in the supply of edible oils that are uncommon in Western countries. Much of the increase in sales of sugar-sweetened beverages and packaged foods is attributable to a handful of multinational corporations, but typically from products distributed through domestic production systems rather than foreign importation. While North America and Latin America continued to have high sugar-sweetened beverage and packaged food sales in recent years, Eastern Europe and the Middle East have become emerging markets for these products. These findings suggest further study of natural experiments to identify which policies may mitigate nutritional risk factors for chronic disease in the context of economic development.

Taxes on sugar-sweetened beverages to curb future obesity and diabetes epidemics

In a linked Perspective, Tony Blakely and colleagues discuss the real-world implications of this type of modeling study. Please see later in the article for the Editors' Summary

Overview: Bellagio Conference on Program and Policy Options for Preventing Obesity in the Low- and Middle-Income Countries

The Bellagio 'Conference on Program and Policy Options for Preventing Obesity in the Low- and Middle-Income Countries' (LMICs) was organized to pull together the current. We need not reiterate the importance of this topic or the speed of change in eating, drinking and moving facing us across the globe. The conference emerges from need to significantly step up the policies and programs to reduce obesity by learning from some current examples of best practice and strengthening the role of the academic and civil society players in translating global evidence and experience into action at the national level. There is also a need to empower the younger generation of scholars and activists in these countries to carry on this effort. The meeting was also timely because a number of funding agencies in the United States, Canada and the UK, at least, are beginning to focus attention on this topic. This set of papers provides not only examples of existing best practice but also a road map ahead for LMICs in the various areas of action needed to reduce obesity across LMICs. The meeting highlighted critical barriers to implementation that have blocked many initiatives.