Public Policies on Obesity: A Literature Review of Global Challenges and Response Strategies

As a complex and multifactorial health problem, obesity results from the interaction of genetic, environmental, dietary, and lifestyle factors. Globally, the increase in obesity and related chronic diseases has been associated with global trade liberalization, rapid urbanization, and economic growth. This article is a narrative literature review on the global obesity problem and explores the global challenges of obesity and strategies to address them. The research methodology included a retrieval of peer-reviewed articles, including PubMed, ScienceDirect, and Google Scholar. Specific search terms like "obesity", "policy", "nutrition", and "global", outline the impact of obesity on global health and social systems, as well as policy effectiveness and gaps that exist. The outcome reveals regional differences in obesity rates and provides an analysis of the policies that countries have implemented to address obesity and their effectiveness, in particular concerning improving the quality of diets and limiting the intake of added sugars. Despite some policies proving effective, the challenge of obesity is far from being fully addressed, necessitating robust international efforts and strategies.

Investigation of the 1-week effect of traffic light nutrition labeling on diet selection among Japanese university students: a randomized controlled trial

BACKGROUND

The method of displaying nutrition information labels on the front of food packaging (FOP: Front of Pack) has been implemented worldwide to prevent lifestyle-related diseases. This study aimed to investigate whether the use of the UK's Traffic Light Food (TLF) label, known as the FOP label, influences the dietary choices of Japanese youth and promotes healthy dietary choices.

METHODS

Diet selection was performed for one week each during the baseline and intervention periods. During the intervention period, TLF labels were displayed on meal images of the intervention group. Participants chose what they would like to have for dinner of the day from 15 images. Each meal was scored based on the color of the nutrition label, and a comparison between groups was made to determine whether TLF labeling influenced meal selection for dinner. The psychological stress caused by the presence or absence of nutrition labels and nutritional components when choosing meals was also evaluated.

RESULTS

A total of 69 participants were randomly assigned to two groups. Dietary choice scores indicated that the TLF-labeled group made significantly healthier dietary choices than the unlabeled group. Additionally, the TLF-labeled group showed a significant increase in the percentage of people conscious of nutritional components when choosing meals. Furthermore, a significant increase in the number of people conscious of protein, a nutritional ingredient not indicated on the TLF label, was observed. During the test period, no difference in psychological stress caused by the presence and absence of the TLF labels was observed.

CONCLUSIONS

The use of TLF labels also encouraged healthy dietary choices among Japanese university students. The use of FOP nutrition labels should be considered in Japan to prevent lifestyle-related diseases through healthy dietary choices.

TRIAL REGISTRATION

UMIN Clinical Trials Registry Number: UMIN000047268. Registered March 23, 2022.

Effectiveness of Displaying Traffic Light Food Labels on the Front of Food Packages in Japanese University Students: A Randomized Controlled Trial

Nutrition labeling on the front of food packages has been implemented worldwide to help improve public health awareness. In this randomized double-blind controlled trial, we used a Google Forms questionnaire to evaluate the effectiveness of nutrition labeling on food packages in university students. The questionnaire, ultimately completed by 247 students, included 15 dietary images from which they were asked to choose what they wanted to eat for breakfast, lunch, and dinner the following day. For the interventional (traffic light food [TLF]) group only, TLF labels were displayed on dietary images. This group had a significantly higher proportion of people conscious of healthy eating during all meals than the control group, and the effect of TLF labeling on choosing meals was the highest for lunch. In addition to the indicated nutritional components, the TLF group had a significantly higher proportion of people who were conscious of the ones of protein and dietary fiber that were not indicated on the label. The use of TLF labels resulted in an increase in the proportion of people choosing a healthy diet as well as being conscious of their nutritional components. Therefore, the use of TLF labels may help promote healthy dietary choices in Japan.

Status of nutrition labeling knowledge, attitude, and practice (KAP) of residents in the community and structural equation modeling analysis

Objective

Unhealthy foods were a major contributor to the occurrence of chronic non-communicable diseases. The promotion of nutrition labeling in the community can effectively help residents to choose healthy foods, which plays an important role in the prevention of chronic diseases. However, the public awareness of this measure is not clear. Our study used a structural equation model based on the KAP theory to analyze the interaction mechanisms among knowledge, attitude, and practice and aimed to evaluate the relationships among nutrition knowledge, attitude, and practice of residents, which can provide the basis of policy formulation for nutrition education and behavior intervention.

Methods

We carried out a cross-sectional study from May 2022 to July 2022 in the "Community Health Service Center", and each "Community Service Station" in Yinchuan use a self-designed questionnaire and convenience sampling to evaluate resident nutrition labeling KAP status. This study adopted the structural equation modeling approach to analyze a survey of Chinese individuals through the cognitive processing model, interrelated nutrition knowledge, nutrition label knowledge, attitude, and practice.

Results

According to the principle of sample size estimation, a total of 636 individuals were investigated, with the ratio of male to female being 1:1.2. The average score of community residents' nutrition knowledge was 7.48 ± 3.24, and the passing rate was 19.4%. Most residents had a positive attitude toward nutrition labeling, but the awareness rate was only 32.7% and the utilization rate was 38.5%. Univariate analysis showed that women had higher knowledge scores than men (p < 0.05), and young people had higher scores than older adults (p < 0.05), and the difference was significant. Based on the KAP structural equation model (SEM), residents' nutrition knowledge will directly affect their attitude toward nutrition labeling. Attitude played a greater role as an indirect effect between knowledge and behavior, while trust limits residents' practice of nutrition labeling and then affects their practice. It could be explained that nutrition knowledge was the prerequisite for label reading behavior, and attitude was the intermediary effect.

Conclusion

The nutrition knowledge and nutrition labeling knowledge of respondents hardly directly support the practice of nutrition labeling, but it can influence the use behavior by forming a positive attitude. The KAP model is suitable for explaining residents' use of nutrition labeling in the region. Future research should focus on better understanding the motivations of residents to use nutrition labeling and the opportunity to use nutrition labeling in real-life shopping settings.

Global cirrhosis prevalence trends and attributable risk factors-an ecological study using data from 1990-2019

BACKGROUND AND AIMS

Cirrhosis is a major public health issue worldwide with significant morbidity and mortality. We aimed to explore the time series associations between varying levels of risk factors and cirrhosis prevalence and predict the cirrhosis prevalence under alternative scenarios to consolidate evidence for further intervention plans.

METHODS

We collected data of cirrhosis and its risk factors from 1990 to 2019 across 178 countries and used a generalized linear mixed model to explore the time series associations between cirrhosis and risk factors. We simulated scenarios with varying levels of risk factors and investigated benefits gained from the control of risk factors compared with the status quo.

RESULTS

The global cirrhosis prevalence varied geographically, with the highest observed in East and Southeast Asia, mainly due to high hepatitis prevalence. Our study revealed that each 1% increase in prevalence of hepatitis B and C, cirrhosis prevalence would correspondingly increase 0.028% and 0.288%. There would be approximately 392.15 million fewer cirrhosis patients if the goals of a 65% reduction in prevalence of hepatitis and a 10% reduction in alcohol consumption were achieved.

CONCLUSIONS

Given that cirrhosis prevalence has different risk factors depending on geography, it is important to identify an appropriate set of interventions for cirrhosis that are adapted to the epidemiological situation in a specific country. Interventions targeting hepatitis may have a significant impact on global cirrhosis prevalence, therefore, the adoption of specific interventions for hepatitis in high-burden regions and high-risk groups is warranted to lower the global burden of cirrhosis.

Brain Responses to High-Calorie Visual Food Cues in Individuals with Normal-Weight or Obesity: An Activation Likelihood Estimation Meta-Analysis

Overconsumption of high-calorie or unhealthy foods commonly leads to weight gain. Understanding people’s neural responses to high-calorie food cues might help to develop better interventions for preventing or reducing overeating and weight gain. In this review, we conducted a coordinate-based meta-analysis of functional magnetic resonance imaging studies of viewing high-calorie food cues in both normal-weight people and people with obesity. Electronic databases were searched for relevant articles, retrieving 59 eligible studies containing 2410 unique participants. The results of an activation likelihood estimation indicate large clusters in a range of structures, including the orbitofrontal cortex (OFC), amygdala, insula/frontal operculum, culmen, as well as the middle occipital gyrus, lingual gyrus, and fusiform gyrus. Conjunction analysis suggested that both normal-weight people and people with obesity activated OFC, supporting that the two groups share common neural substrates of reward processing when viewing high-calorie food cues. The contrast analyses did not show significant activations when comparing obesity with normal-weight. Together, these results provide new important evidence for the neural mechanism underlying high-calorie food cues processing, and new insights into common and distinct brain activations of viewing high-calorie food cues between people with obesity and normal-weight people.

Daily associations between alcohol and sweets craving and consumption in early AUD recovery: Results from an ecological momentary assessment study

INTRODUCTION

Alcohol cravings can predict relapse in persons with alcohol use disorder (AUD). Consuming sweets is a commonly recommend strategy to quell alcohol cravings in early recovery from AUD, yet research is equivocal on whether consuming sweets mitigates alcohol cravings or relapse risk. The current study used ecological momentary assessment (EMA) data to examine real-time alcohol cravings, sweet cravings, and consumption of sweets among adults in early recovery from AUD.

METHODS

We used EMA methods to follow 25 adults (n = 14 women, 56%; M. age 40, S.D. 10.68) recently discharged from a partial hospitalization program for AUD for 21 days. Prompts were sent to the participants for completion four times per day via a mobile app. EMA data were disaggregated prior to analysis to examine between- and within-person effects. A series of three mixed linear models tested: 1) the contemporaneous effect of sweet and alcohol cravings, 2) alcohol cravings predicting sweet consumption later in the day, and 3) sweet consumption predicting alcohol craving later in the day.

RESULTS

The results of the first model revealed alcohol cravings were associated with sweet cravings early in recovery. In the second model, no effect occurred between alcohol cravings earlier in the day predicting sweet consumption later in the day. The third model suggested consuming sweets earlier in the day predicted higher alcohol cravings later in the day.

DISCUSSION

Sweet craving and consumption are associated with alcohol cravings among adults in early recovery from AUD. These findings suggest consuming sweets may increase alcohol cravings. If future studies can replicate this result, consuming sweets in early recovery may emerge as a potential risk for relapse in this population.

Do Disadvantageous Social Contexts Influence Food Choice? Evidence From Three Laboratory Experiments

Increasing rates of obesity have fueled interest in the factors underlying food choice. While epidemiological studies report that disadvantaged social groups exhibit a higher incidence of obesity, causal evidence for an effect of social contexts on food choice remains scarce. To further our knowledge, we experimentally investigated the effect of disadvantageous social context on food choice in healthy, non-dieting participants. We used three established experimental methods to generate social contexts of different valence in controlled laboratory settings: (i) receiving varying amounts of money in a Dictator Game (DG; n = 40), (ii) being included or excluded in a Cyberball Game (CBG; n = 35), and (iii) performing well, average, or poorly in a response time ranking task (RTR; n = 81). Following exposure to a particular social context, participants made pairwise choices between food items that involved a conflict between perceived taste and health attributes. In line with previous research, stronger dispositional self-control (assessed via a questionnaire) was associated with healthier food choices. As expected, being treated unfairly in the DG, being excluded in the CBG, and performing poorly in the RTR led to negative emotions. However, we did not find an effect of the induced social context on food choice in any of the experiments, even when taking into account individual differences in participants’ responses to the social context. Our results suggest that—at least in controlled laboratory environments—the influence of disadvantageous social contexts on food choice is limited.

Regulating food craving: From mechanisms to interventions

Craving, defined here as a strong desire to eat, is a common experience that drives behavior. Here we discuss the concept of craving from historical, physiological, and clinical perspectives, and review work investigating the effects of cue reactivity and cue-induced craving on eating and weight outcomes, as well as underlying neural mechanisms. We also highlight the significance of cue reactivity and craving in the context of our "toxic food environment" and the obesity epidemic. We then summarize our work developing the Regulation of Craving (ROC) task, used to test the causal effects of cognitive strategies on craving for food and drugs as well as the underlying neural mechanisms of such regulation. Next, we review our recent development of a novel ROC-based intervention that trains individuals to use cognitive strategies to regulate craving, with promising effects on subsequent food choice and caloric consumption. We end by discussing future directions for this important line of work.

Ethical, Stigma, and Policy Implications of Food Addiction: A Scoping Review

The concept of food addiction has generated much controversy. In comparison to research examining the construct of food addiction and its validity, relatively little research has examined the broader implications of food addiction. The purpose of the current scoping review was to examine the potential ethical, stigma, and health policy implications of food addiction. Major themes were identified in the literature, and extensive overlap was identified between several of the themes. Ethics sub-themes related primarily to individual responsibility and included: (i) personal control, will power, and choice; and (ii) blame and weight bias. Stigma sub-themes included: (i) the impact on self-stigma and stigma from others, (ii) the differential impact of substance use disorder versus behavioral addiction on stigma, and (iii) the additive stigma of addiction plus obesity and/or eating disorder. Policy implications were broadly derived from comparisons to the tobacco industry and focused on addictive foods as opposed to food addiction. This scoping review underscored the need for increased awareness of food addiction and the role of the food industry, empirical research to identify specific hyperpalatable food substances, and policy interventions that are not simply extrapolated from tobacco.

"There is no way to avoid the first bite": A qualitative investigation of addictive-like eating in treatment-seeking Brazilian women and men

There has been polarizing debate on addictive-like eating in recent years. To move toward valid definition and measurement of this construct, qualitative research describing individuals' experiences is needed. The present study explored how Brazilian men and women define and experience addictive-like eating. Interviews were conducted with 7 men and 8 women (M_age = 46.6 years, M_BMI = 35.43 kg/m²) seeking treatment for addictive-like eating. Thematic analysis of interviews identified three saturated, overarching themes describing participants' conceptualizations of the (1) characteristics, (2) causal factors, and (3) consequences of addictive-like eating. Lack of control was a key characteristic of addictive-like eating described by all participants. A causal factor which most participants described was emotional eating. Consequences included emotional, interpersonal, occupational, and health-related impairments which appeared primarily related to weight gain, rather than to the pattern of addictive-like eating itself. These results are largely consistent with those of previous qualitative studies. Importantly, the symptoms described by our participants and in previous qualitative studies may be inadequately captured by existing self-report questionnaires designed to assess addictive-like eating. To address this potential limitation, we provide recommendations for assessing the full range of possible addictive-like eating symptoms.

Training in cognitive strategies reduces eating and improves food choice

Obesity rates continue to rise alarmingly, with dire health implications. One contributing factor is that individuals frequently forgo healthy foods in favor of inexpensive, high-calorie, unhealthy foods. One important mechanism underlying these choices is food craving: Craving increases with exposure to unhealthy foods (and food cues, such as advertisements) and prospectively predicts eating and weight. Prior work has shown that cognitive regulation strategies that emphasize the negative consequences of unhealthy foods reduce craving. In Studies 1 and 2, we show that cognitive strategies also increase craving for healthy foods by emphasizing their positive benefits, and change food valuation (willingness to pay) for both healthy and unhealthy foods. In Studies 3 and 4, we demonstrate that brief training in cognitive strategies ("Regulation of Craving Training"; ROC-T) increases subsequent healthy (vs. unhealthy) food choices. This was striking because this change in food choices generalized to nontrained items. Importantly, in Study 5, we show that brief training in cognitive strategies also reduces food consumption by 93-121 calories. Consumed calories correlated with changes in food choice. Finally, in Study 6, we show that the training component of ROC-T is necessary, above and beyond any effect of framing. Across all studies (NTOTAL = 1,528), we find that cognitive strategies substantially change craving and food valuation, and that training in cognitive strategies improves food choices by 5.4-11.2% and reduces unhealthy eating, including in obese individuals. Thus, these findings have important theoretical, public health, and clinical implications for obesity prevention and treatment.

Influence of Being Embodied in an Obese Virtual Body on Shopping Behavior and Products Perception in VR

Research in Virtual Reality (VR) showed that embodiment can influence participants' perceptions and behavior when embodied in a different yet plausible virtual body. In this paper, we study the changes an obese virtual body has on products perception (e.g., taste, etc.) and purchase behavior (e.g., number purchased) in an immersive virtual retail store. Participants (of a normal BMI on average) were embodied in a normal (N) or an obese (OB) virtual body and were asked to buy and evaluate food products in the immersive virtual store. Based on stereotypes that are classically associated with obese people, we expected that the group embodied in obese avatars would show a more unhealthy diet, (i.e., buy more food products and also buy more products with high energy intake, or saturated fat) and would rate unhealthy food as being tastier and healthier than participants embodied in “normal weight” avatars. Our participants also rated the perception of their virtual body: the OB group perceived their virtual body as significantly heavier and older. They also rated their sense of embodiment and presence within the immersive virtual store. These measures did not show any significant difference between groups. Finally, we asked them to rate different food products in terms of tastiness, healthiness, sustainability and price. The only difference we noticed is that participants embodied in an obese avatar (OB group) rated the coke as being significantly tastier and the apple as being significantly healthier. Nevertheless, while we hypothesized that participants embodied in a virtual body with obesity would show differences in their shopping patterns (e.g., more “unhealthy” products bought) there were no significant differences between the groups. Stereotype activation failed for our participants embodied in obese avatars, who did not exhibit a shopping behavior following the (negative) stereotypes related to obese people. conversely, while the opposite hypothesis (participants embodied in obese avatars would buy significantly more healthy products in order to “transform” their virtual bodies) could have been made, it was not the case either. We discuss these results and propose hypotheses as to why the behavior of the manipulated group differed from the one we expected. Indeed, unlike previous research, our participants were embodied in virtual avatars which differed greatly from their real bodies. Obese avatars should not only modify users' visual characteristics such as hair or skin color, etc. We hypothesize that an obese virtual body may require some other non-visual stimulus, e.g., the sensation of the extra weight or the change in body size. This main difference could then explain why we did not notice any important modification on participants' behavior and perceptions of food products. We also hypothesize that the absence of stereotype activation and thus of statistical difference between our N and OB groups might be due to higher-level cognitive processes involved while purchasing food products. Indeed our participants might have rejected their virtual bodies when performing the shopping task, while the embodiment and presence ratings did not show significant differences, and purchased products based on their real (non-obese) bodies. This could mean that stereotype activation is more complex that previously thought.

Obesity and the food system transformation in Latin America

The Latin America and the Caribbean (LAC) region faces a major diet-related health problem accompanied by enormous economic and social costs. The shifts in diet are profound: major shifts in intake of less-healthful low-nutrient-density foods and sugary beverages, changes in away-from-home eating and snacking and rapid shifts towards very high levels of overweight and obesity among all ages along with, in some countries, high burdens of stunting. Diet changes have occurred in parallel to, and in two-way causality with, changes in the broad food system - the set of supply chains from farms, through midstream segments of processing, wholesale and logistics, to downstream segments of retail and food service (restaurants and fast food chains). An essential contribution of this piece is to marry and integrate the nutrition transition literature with the literature on the economics of food system transformation. These two literatures and debates have been to date largely 'two ships passing in the night'. This review documents in-depth the recent history of rapid growth and transformation of that broad food system in LAC, with the rapid rise of supermarkets, large processors, fast food chains and food logistics firms. The transformation is the story of a 'double-edged sword', showing its links to various negative diet side trends, e.g. the rise of consumption of fast food and highly processed food, as well as in parallel, to various positive trends, e.g. the reduction of the cost of food, de-seasonalization, increase of convenience of food preparation reducing women's time associated with that and increase of availability of some nutritious foods like meat and dairy. We view the transformation of the food system, as well as certain aspects of diet change linked to long-run changes in employment and demographics (e.g. the quest for convenience), as broad parameters that will endure for the next decades without truly major regulatory and fiscal changes. We then focus in on what are the steps that are being and can be taken to curb the negative effects on diet of these changes. We show that countries in LAC are already among the global leaders in initiating demand-related solutions via taxation and marketing controls. But we also show that this is only a small step forward. To shift LAC's food supply towards prices that incentivize consumption of healthier diets and demand away from the less healthy component is not simple and will not happen immediately. We must be cognizant that ultimately, food industry firms must be incentivized to market the components of healthy diets. This will primarily need to be via selective taxes and subsidies, marketing controls, as well as food quality regulations, consumer education and, in the medium term, consumers' desires to combine healthier foods with their ongoing quest for convenience in the face of busy lives. In the end, the food industry in LAC will orient itself towards profitable solutions, ie those demanded by the broad mass of consumers.

"I only watch for the commercials": Messages about weight, eating and race in Super Bowl advertisements

OBJECTIVE

Health experts and communication experts assert that the media influence individuals' health. Yet, incongruously, the public, policy-makers and the media themselves appear reticent to accept that the media could have extensive negative influence on health.

METHODS

The current study examined all ads that aired from Super Bowl XLVI through Super Bowl XLIX (N = 241) using a detailed, multistep coding process.

RESULTS

Ads had similar racial/ethnic diversity in the full sample and food/beverage ads. A minority (14.5%) of advertisements contained actors with overweight/obesity, who were more likely to be White and less likely to be Hispanic compared with race/ethnicity in all ads. Humour and tone were similarly present whether or not the ads included actors with overweight/obesity.

CONCLUSIONS

Findings are striking given the high prevalence of overweight/obesity in the USA, particularly among Black and Hispanic populations, and the comparatively low representation of actors with overweight/obesity in Super Bowl advertisements. Surprising weight findings may signal a change in how the media portray body-size norms (away from exclusively thin), although representations remain disproportionate from actual body-size distributions in the USA.

Multidimensional assessment of impulsivity in relation to obesity and food addiction

Based on similarities between overconsumption of food and addictive drugs, there is increasing interest in "food addiction," a compulsive eating pattern defined using symptoms parallel to substance use disorders. Impulsivity, a multidimensional construct robustly linked to drug addiction, has been increasingly examined as an obesity determinant, but with mixed findings. This study sought to clarify relations between three major domains of impulsivity (i.e., impulsive personality traits, discounting of delayed rewards, and behavioral inhibition) in both obesity and food addiction. Based on the association between impulsivity and compulsive drug use, the general hypothesis was that the impulsivity-food addiction relation would be stronger than and responsible for the impulsivity-obesity relation. Using a cross-sectional dimensional design, participants (N = 181; 32% obese) completed a biometric assessment, the Yale Food Addiction Scale (YFAS), the UPPS-P Impulsive Behavior Scales, a Go/NoGo task, and measures of monetary delay discounting. Results revealed significantly higher prevalence of food addiction among obese participants and stronger zero-order associations between impulsivity indices and YFAS compared to obesity. Two aspects of impulsivity were independently significantly associated with food addiction: (a) a composite of Positive and Negative Urgency, reflecting proneness to act impulsively during intense mood states, and (b) steep discounting of delayed rewards. Furthermore, the results supported food addiction as a mediator connecting both urgency and delay discounting with obesity. These findings provide further evidence linking impulsivity to food addiction and obesity, and suggest that food addiction may be a candidate etiological pathway to obesity for individuals exhibiting elevations in these domains.

Believing that certain foods are addictive is associated with support for obesity-related public policies

INTRODUCTION

There is a growing body of evidence suggesting that certain foods may be addictive. Although evidence that nicotine is addictive generated support for anti-tobacco policies, little research has examined whether beliefs about the addictiveness of food are associated with support for policies to address overconsumption of nutritionally poor foods.

METHODS

U.S. adults (n=999) recruited from an online marketplace in February 2015 completed a survey. Using logistic regression, we examined the relationship between beliefs about the addictiveness of certain foods and support for twelve obesity-related policies while controlling for demographics, health status, political affiliation and ideology, beliefs about obesity, and attitudes towards food companies. We examined whether the association between beliefs about addictiveness and support for policies was consistent across other products and behaviors viewed as addictive (i.e., tobacco, alcohol, drugs, compulsive behaviors).

RESULTS

In multivariable models, there was a significant association (OR; 95% CI) between beliefs about addictiveness and support for policies for compulsive behaviors (1.48; 1.26-1.74), certain foods (1.32; 1.14-1.53), drugs (1.23; 1.05-1.45), and alcohol (1.21; 1.08-1.36) but not for tobacco (1.11; 0.90-1.37). For foods, the association between beliefs about addictiveness and obesity-related policy support was the strongest between such beliefs and support for labels warning that certain foods may be addictive, industry reductions in salt and sugar, energy drink bans, and sugary drink portion size limits.

CONCLUSIONS

Overall, believing that products/behaviors are addictive was associated with support for policies intended to curb their use. If certain foods are found to be addictive, framing them as such may increase obesity-related policy support.

Cardiovascular Risk Factors of Adults Age 20-49 Years in the United States, 1971-2012: A Series of Cross-Sectional Studies

Background

The health of younger adults in the U.S. has important public health and economic-related implications. However, previous literature is insufficient to fully understand how the health of this group has changed over time. This study examined generational differences in cardiovascular risk factors of younger adults over the past 40 years.

Methods

Data were from 6 nationally representative cross-sectional National Health and Nutrition Examination Surveys (1971–2012; N = 44,670). Participants were adults age 20–49 years who self-reported sociodemographic characteristics and health conditions, and had examination/laboratory measures for hypertension, hyperlipidemia, diabetes, obesity, and chronic kidney disease. Prevalences of sociodemographic characteristics and health status were determined by study period. Logistic regression was used to determine the odds [odds ratio (OR), 95% confidence interval] of health conditions by study period: models adjusted only for age, sex, and race, and fully adjusted models additionally adjusted for socioeconomic characteristics, smoking, BMI, diabetes, and/or hypertension (depending on the outcome) were assessed.

Results

Participants in 2009–2012 were significantly more likely to be obese and have diabetes compared to those in 1971–1975 (OR = 4.98, 3.57–6.97; OR = 3.49, 1.59–7.65, respectively, fully adjusted). Participants in 2009–2012 vs. 1988–1994 were significantly more likely to have had hypertension but uncontrolled hypertension was significantly less likely (OR = 0.67, 0.52–0.86, fully adjusted). There was no difference over time for high cholesterol, but uncontrolled high cholesterol was significantly less likely in 2009–2012 vs. 1988–1994 (OR = 0.80, 0.68–0.94, fully adjusted). The use of hypertensive and cholesterol medications increased while chronic kidney and cardiovascular diseases were relatively stable.

Conclusions

Cardiovascular risk factors of younger U.S. adults have worsened over the past 40 years, but treatment for hypertension and high cholesterol has improved. The sub-optimal and worsening health in younger adults may have a substantial impact on health care utilization and costs, and should be considered when developing health care practices.

The Neurobiology of "Food Addiction" and Its Implications for Obesity Treatment and Policy

There is a growing view that certain foods, particularly those high in refined sugars and fats, are addictive and that some forms of obesity can usefully be treated as a food addiction. This perspective is supported by a growing body of neuroscience research demonstrating that the chronic consumption of energy-dense foods causes changes in the brain's reward pathway that are central to the development and maintenance of drug addiction. Obese and overweight individuals also display patterns of eating behavior that resemble the ways in which addicted individuals consume drugs. We critically review the evidence that some forms of obesity or overeating could be considered a food addiction and argue that the use of food addiction as a diagnostic category is premature. We also examine some of the potential positive and negative clinical, social, and public policy implications of describing obesity as a food addiction that require further investigation.

Food cue reactivity and craving predict eating and weight gain: a meta-analytic review

According to learning-based models of behavior, food cue reactivity and craving are conditioned responses that lead to increased eating and subsequent weight gain. However, evidence supporting this relationship has been mixed. We conducted a quantitative meta-analysis to assess the predictive effects of food cue reactivity and craving on eating and weight-related outcomes. Across 69 reported statistics from 45 published reports representing 3,292 participants, we found an overall medium effect of food cue reactivity and craving on outcomes (r = 0.33, p < 0.001; approximately 11% of variance), suggesting that cue exposure and the experience of craving significantly influence and contribute to eating behavior and weight gain. Follow-up tests revealed a medium effect size for the effect of both tonic and cue-induced craving on eating behavior (r = 0.33). We did not find significant differences in effect sizes based on body mass index, age, or dietary restraint. However, we did find that visual food cues (e.g. pictures and videos) were associated with a similar effect size to real food exposure and a stronger effect size than olfactory cues. Overall, the present findings suggest that food cue reactivity, cue-induced craving and tonic craving systematically and prospectively predict food-related outcomes. These results have theoretical, methodological, public health and clinical implications.

Homeostasis balance, homeostasis imbalance or distinct motivational processes? Comments on Marks (2015) 'Homeostatic Theory of Obesity'

In his article, 'Homeostatic theory of obesity', Marks suggested that imbalances in homeostatic processes could explain weight gain and obesity. He proposes that over-consumption of high-caloric, low-nutrient and low satiating foods, combined with a stressful environment, is the origin of weight gain. Once weight gain occurs, individuals may develop body dissatisfaction and negative affect, leading to continued over-consumption, which sets in motion a system of feedback loops that leads to a Circle of Discontent and further weight gain. In this article, we attempt to clarify certain problematic aspects of Marks framework and identify specific directions that researchers should pursue to address these shortcomings.

Depression, obesity, and metabolic syndrome: prevalence and risks of comorbidity in a population-based representative sample of Mexican Americans

INTRODUCTION

We examined the prevalence of depression, obesity, and metabolic syndrome and associations between them in a population-based representative cohort of Mexican Americans living on the United States-Mexico border.

METHOD

The sample in this cross-sectional analysis consisted of 1,768 Mexican American adults (≥ 18 years of age) assessed between the years 2004 and 2010, with whom we tested our central hypothesis of a significant relationship between obesity and depression. Depression was measured using the Center for Epidemiologic Studies-Depression scale (CES-D) with a cutoff score of ≥ 16 for depression and a cutoff score of ≥ 27 for severe depression. We categorized body mass index (BMI) values as obese (≥ 30kg/m(2)) and later subdivided the obese subjects into obese (30-39 kg/m(2)[inclusive]) and morbidly obese (≥ 40 kg/m(2)). Metabolic syndrome was defined using the American Heart Association definition requiring at least 3 of the following: increased waist circumference, elevated triglycerides, reduced high-density lipoprotein (HDL) cholesterol, elevated blood pressure, and elevated fasting glucose. Weighted data were analyzed to establish prevalence of depression, obesity, and metabolic syndrome. Univariate and multivariable weighted regression models were used to test potential associations between these disorders.

RESULTS

Using weighted prevalence, we observed high rates of depression (30%), obesity (52%), and metabolic syndrome (45%). Univariate models revealed female gender (P = .0004), low education (P = .003), low HDL level (P = .009), and increased waist circumference (P = .03) were associated with depression. Female gender (P = .01), low education (P = .003), and morbid obesity (P = .002) were risk factors for severe depression and remained significant in multivariable models.

CONCLUSIONS

In this large cohort of Mexican Americans, obesity, female gender, and low education were identified risk factors for depression. These indicators may serve as targets for early detection, prevention, and intervention in this population.

Public health policies to encourage healthy eating habits: recent perspectives

There is an urgent need to address unhealthy dietary patterns at the population level. Poor diet and physical inactivity are key drivers of the obesity pandemic, and they are among the leading causes of preventable death and disability in nearly every country in the world. As countries grapple with the growing obesity prevalence, many innovative policy options to reduce overeating and improve diet quality remain largely unexplored. We describe recent trends in eating habits and consequences for public health, vulnerabilities to unhealthy eating, and the role for public health policies. We reviewed recent public health policies to promote healthier diet patterns, including mandates, restrictions, economic incentives, marketing limits, information provision, and environmental defaults.

Socioeconomic modifiers of genetic and environmental influences on body mass index in adult twins

OBJECTIVE

Individual measures of socioeconomic status (SES) suppress genetic variance in body mass index (BMI). Our objective was to examine the influence of both individual-level (i.e., educational attainment, household income) and macrolevel (i.e., neighborhood socioeconomic advantage) SES indicators on genetic contributions to BMI.

METHOD

The study used education level data from 4,162 monozygotic (MZ) and 1,900 dizygotic (DZ) same-sex twin pairs (64% female), income level data from 3,498 MZ and 1,534 DZ pairs (65% female), and neighborhood-level socioeconomic deprivation data from 2,327 MZ and 948 DZ pairs (65% female). Covariates included age (M = 40.4 ± 17.5 years), sex, and ethnicity. The cotwin control model was used to evaluate the mechanisms through which SES influences BMI (e.g., through genetic vs. environmental pathways), and a gene-by-environment interaction model was used to test whether residual variance in BMI, after controlling for the main effects of SES, was moderated by socioeconomic measures.

RESULTS

SES significantly predicted BMI. The association was noncausal, however, and instead was driven primarily through a common underlying genetic background that tended to grow less influential as SES increased. After controlling for the main effect of SES, both genetic and nonshared environmental variance decreased with increasing SES.

CONCLUSIONS

The impact of individual and macrolevel SES on BMI extends beyond its main effects. The influence of genes on BMI is moderated by individual and macrolevel measures of SES, such that when SES is higher, genetic factors become less influential.

Patchy progress on obesity prevention: emerging examples, entrenched barriers, and new thinking

Despite isolated areas of improvement, no country to date has reversed its obesity epidemic. Governments, together with a broad range of stakeholders, need to act urgently to decrease the prevalence of obesity. In this Series paper, we review several regulatory and non-regulatory actions taken around the world to address obesity and discuss some of the reasons for the scarce and fitful progress. Additionally, we preview the papers in this Lancet Series, which each identify high-priority actions on key obesity issues and challenge some of the entrenched dichotomies that dominate the thinking about obesity and its solutions. Although obesity is acknowledged as a complex issue, many debates about its causes and solutions are centred around overly simple dichotomies that present seemingly competing perspectives. Examples of such dichotomies explored in this Series include personal versus collective responsibilities for actions, supply versus demand-type explanations for consumption of unhealthy food, government regulation versus industry self-regulation, top-down versus bottom-up drivers for change, treatment versus prevention priorities, and a focus on undernutrition versus overnutrition. We also explore the dichotomy of individual versus environmental drivers of obesity and conclude that people bear some personal responsibility for their health, but environmental factors can readily support or undermine the ability of people to act in their own self-interest. We propose a reframing of obesity that emphasises the reciprocal nature of the interaction between the environment and the individual. Today's food environments exploit people's biological, psychological, social, and economic vulnerabilities, making it easier for them to eat unhealthy foods. This reinforces preferences and demands for foods of poor nutritional quality, furthering the unhealthy food environments. Regulatory actions from governments and increased efforts from industry and civil society will be necessary to break these vicious cycles.

Use of psychology and behavioral economics to promote healthy eating

Understanding the psychology of how people make decisions can shed light on important factors contributing to the cause and maintenance of public health problems like obesity. This knowledge can and should inform the design of government and private-sector public health interventions. Several insights from psychology and behavioral economics that help explain why people are particularly vulnerable to the current food environment are discussed. These insights fall into the following categories: the influence of starting points (status quo bias and anchoring effects); communicating health information (simplicity and framing); and unintended consequences of policy interventions (compensation, substitution, and the peanuts effect). The paper discusses opportunities for improving the design of food policies and interventions by altering default options, providing the public with simple and meaningful nutrition information, carefully constructing the framing of public health messages, and designing food policies to minimize unintended consequences, such as compensation and substitution.

Food addiction and its impact on weight-based stigma and the treatment of obese individuals in the U.S. and Australia

It is argued that food addiction explanations of obesity may reduce the significant stigma levelled at obese and overweight individuals. We surveyed 479 adults to determine the prevalence of food addiction in the U.S. (n = 215) and, for the first time, in Australia (n = 264) using the Yale Food Addiction Scale (YFAS). We also assessed the level of weight-based stigma in this population. The prevalence of food addiction in our Australian sample was 11%, similar to U.S. participants and consistent with previous studies. Those who met criteria for diagnosis had a larger mean BMI (33.8 kg/m²) than those who did not (26.5 kg/m²). Overall, the level of stigma towards others was low and differed significantly based on BMI, predominately among normal weight and obese participants (p = 0.0036). Obese individuals scored higher on certain measures of stigma, possibly reflecting individual experiences of stigma rather than negative attitudes towards other obese individuals (p = 0.0091). Despite significant support for a “food addiction” explanation of obesity, participants still valued personal responsibility in overcoming obesity and did not support coercive approaches to treat their “addiction”.

Measuring internalized weight attitudes across body weight categories: validation of the modified weight bias internalization scale

The purpose of this research was to validate a modified version of the Weight Bias Internalization Scale (WBIS-M) that is applicable to individuals across different body weight statuses. One hundred forty-eight men and women completed an online survey that included the WBIS-M and relevant measures of psychopathology. Results indicated that the WBIS-M had high internal consistency and strong construct validity. The WBIS-M also demonstrated significant correlations with body image, eating pathology, self-esteem, and symptoms of anxiety and depression, and was associated with these outcomes distinctly from antifat attitudes and body mass index. Implications for the use of this scale in diverse samples are discussed.

Economic analyses of the Be Fit Be Well program: a weight loss program for community health centers

BACKGROUND

The U.S. Preventive Services Task Force has released new guidelines on obesity, urging primary care physicians to provide obese patients with intensive, multi-component behavioral interventions. However, there are few studies of weight loss in real world nonacademic primary care, and even fewer in largely racial/ethnic minority, low-income samples.

OBJECTIVE

To evaluate the recruitment, intervention and replications costs of a 2-year, moderate intensity weight loss and blood pressure control intervention.

DESIGN

A comprehensive cost analysis was conducted, associated with a weight loss and hypertension management program delivered in three community health centers as part of a pragmatic randomized trial.

PARTICIPANTS

Three hundred and sixty-five high risk, low-income, inner city, minority (71 % were Black/African American and 13 % were Hispanic) patients who were both hypertensive and obese.

MAIN MEASURES

Measures included total recruitment costs and intervention costs, cost per participant, and incremental costs per unit reduction in weight and blood pressure.

KEY RESULTS

Recruitment and intervention costs were estimated $2,359 per participant for the 2-year program. Compared to the control intervention, the cost per additional kilogram lost was $2,204 /kg, and for blood pressure, $621 /mmHg. Sensitivity analyses suggest that if the program was offered to a larger sample and minor modifications were made, the cost per participant could be reduced to the levels of many commercially available products.

CONCLUSIONS

The costs associated with the Be Fit Be Well program were found to be significantly more expensive than many commercially available products, and much higher than the amount that the Centers for Medicare and Medicaid reimburse physicians for obesity counseling. However, given the serious and costly health consequences associated with obesity in high risk, multimorbid and socioeconomically disadvantaged patients, the resources needed to provide interventions like those described here may still prove to be cost-effective with respect to producing long-term behavior change.

Public views on food addiction and obesity: implications for policy and treatment

Background

According to their advocates, neurobiological explanations of overeating, or “food addiction”, have the potential to impact public understanding and treatment of obesity. In this study, we examine the public’s acceptance of the concept of food addiction as an explanation of overeating and assess its effects upon their attitudes toward obese persons and the treatment of obesity.

Methods and Findings

We conducted an online survey of 479 adults from the US (n = 215) and Australia (n = 264). There was substantial support for the idea of food addiction, particularly among obese participants. Over half favoured treating obesity as a type of addiction. Psychotherapy was believed to be the most effective treatment and educational and support programs were the preferred policies to address food addiction. There was very little support for increasing taxes on obesogenic foods. Despite the strong support for seeing obesity as a form of addiction, respondents still saw obesity as primarily the result of personal choices and emphasized the need for individuals to take responsibility for their eating.

Conclusions

Our sample of the general public strongly supported the idea of obesity as a form of food addiction; but this did not translate into support of clinical and public health policies that experts believe are most likely to reduce the prevalence of obesity. The reasons for the apparent disjunction between support for food addiction and a strong emphasis on personal choice for weight warrant further examination.

Taxing junk food to counter obesity

We examined the advantages and disadvantages of implementing a junk food tax as an intervention to counter increasing obesity in North America. Small excise taxes are likely to yield substantial revenue but are unlikely to affect obesity rates. High excise taxes are likely to have a direct impact on weight in at-risk populations but are less likely to be politically palatable or sustainable. Ultimately, the effectiveness of earmarked health programs and subsidies is likely to be a key determinant of tax success in the fight against obesity.

Obesity Prevention Policies in U.S. States and Localities: Lessons from the Field

Obesity is a complex problem requiring large-scale, population-based solutions. Public policy strategies have been identified as critical tools in obesity prevention efforts as they can benefit all who are exposed rather than simply changing individual behaviors one at a time. This paper reviews the peer-reviewed scientific U.S.-based literature published between January 2012 and March 2013 to examine the influence of state laws and local policies on changes to school and other environments, individual activity and nutrition-related behaviors, and obesity and weight outcomes. Virtually all recent studies have focused on policies directed at the school environment and, across-the board, the evidence was mixed. Most studies were cross-sectional, focused on policy implementation in schools and other settings rather than impacts on individual behaviors or obesity. Opportunities exist for impact studies focusing on a broader spectrum of policies as well as for continued policy actions at all levels of government.

From passive overeating to "food addiction": a spectrum of compulsion and severity

A psychobiological dimension of eating behaviour is proposed, which is anchored at the low end by energy intake that is relatively well matched to energy output and is reflected by a stable body mass index (BMI) in the healthy range. Further along the continuum are increasing degrees of overeating (and BMI) characterized by more severe and more compulsive ingestive behaviours. In light of the many similarities between chronic binge eating and drug abuse, several authorities have adopted the perspective that an apparent dependence on highly palatable food-accompanied by emotional and social distress-can be best conceptualized as an addiction disorder. Therefore, this review also considers the overlapping symptoms and characteristics of binge eating disorder (BED) and models of food addiction, both in preclinical animal studies and in human research. It also presents this work in the context of the modern and "toxic" food environment and therein the ubiquitous triggers for over-consumption. We complete the review by providing evidence that what we have come to call "food addiction" may simply be a more acute and pathologically dense form of BED.

Is food addiction a valid and useful concept?

In this paper, we consider the concept of food addiction from a clinical and neuroscientific perspective. Food addiction has an established and growing currency in the context of models of overeating and obesity, and its acceptance shapes debate and research. However, we argue that the evidence for its existence in humans is actually rather limited and, in addition, there are fundamental theoretical difficulties that require consideration. We therefore review food addiction as a phenotypic description, one that is based on overlap between certain eating behaviours and substance dependence. To begin, we consider limitations in the general application of this concept to obesity. We share the widely held view that such a broad perspective is not sustainable and consider a more focused view: that it underlies particular eating patterns, notably binge eating. However, even with this more specific focus, there are still problems. Validation of food addiction at the neurobiological level is absolutely critical, but there are inconsistencies in the evidence from humans suggesting that caution should be exercised in accepting food addiction as a valid concept. We argue the current evidence is preliminary and suggest directions for future work that may provide more useful tests of the concept.