Free will and the obesity epidemic

Food Allergy, Nutrition, Psychology, and Health

This article explores food allergy and the nascent field of nutritional psychiatry. Individuals with food allergy experience lower levels of "food freedom" than their nonallergic counterparts, which can create cognitive, emotional, social, nutritional, and financial burdens. Patterns of food avoidance may influence neuroinflammatory states and the gut microbiome; these changes may be associated with neuropsychiatric symptoms. Food restriction may promote disruption of the microbiome neuroimmune axis, which has been linked to various allergic diseases. Targeted psychological counseling strategies can provide benefit. Food allergy and restricted diets may impact dietary health benefits.

Exploring the priorities of ageing populations in Pakistan, comparing views of older people in Karachi City and Thatta

As a lower middle-income country, Pakistan faces multiple issues that influence the course of healthy ageing. Although there is some understanding of these issues and the objective health outcomes of people in Pakistan, there is less knowledge on the perceptions, experiences, and priorities of the ageing population and their caretakers (hereafter, "stakeholders"). The aim of the study was to identify the needs and priorities of older adults and stakeholders across both urban and rural locations. We sought to explore the views of two groups of people, older adults and stakeholders on topics including the definition of ageing as well as areas of importance, services available, and barriers to older people living well. Two-day workshops were conducted in one rural city, Thatta and one urban city, Karachi. The workshops were designed using the Nominal Group Technique, which included plenary and roundtable discussions. The responses were ranked through rounds of voting and a consensus priority list was obtained for each topic and group. Responses were categorized using the socio-ecological framework. Responses were compared between stakeholders and older people and between different geographical areas. 24 urban and 26 rural individuals aged over 60 years and 24 urban and 26 rural stakeholders attended the workshops. There were few areas of agreement with respect to both geographical region and participant group. Comparing older adults' definition of ageing, there was no overlap between the top five ranked responses across urban and rural locations. With respect to areas of importance, there was agreement on free health care as well as financial support. In terms of barriers to healthy ageing, only nation-wide inflation was ranked highly by both groups. In addition, there were relatively few areas of congruence between stakeholder and older adult responses, irrespective of location, although engagement with family, adequate nutrition and monetary benefits were responses ranked by both groups as important for healthy ageing. Both groups ranked issues with the pension system and financial difficulties as barriers. When categorized using the socio-ecological model, across all questions, societal factors were prioritized most frequently (32 responses), followed by individual (27), relationship (15), and environment (14). Overcoming barriers to facilitate healthy ageing will require a multi-faceted approach and must incorporate the priorities of older individuals. Our results may serve as a guide for researchers and policymakers for future engagement and to plan interventions for improving the health of the ageing population in Pakistan.

Priorities and barriers for ageing well; results from stakeholder workshops in rural and urban Rwanda

BACKGROUND

The National Older Person's Policy of 2021 in Rwanda highlights the need for social protection of older populations. However, there is a lack of local knowledge regarding the priorities and challenges to healthy aging faced by older people and their caregivers.

OBJECTIVES

This study aimed to identify and compare the needs and priorities of older people and other stakeholders involved in caring for them in rural and urban areas of Rwanda.

METHODS

The study was conducted in two locations, Kigali (urban) and Burera district (rural). Each site hosted two separate one-day workshops with older people (≥60 years) and stakeholders (all ages). Discussions were held in plenary and roundtable-groups to generate a list of the top 4 prioritized responses on areas of importance, priorities/enablers to be addressed, and obstacles to living a healthy and active life for older people. The research team identified similarities between stakeholder and older people's responses in each area and a socio-ecological model was used to categorize findings.

RESULTS

There were substantial differences in responses between rural and urban areas and between older people and stakeholders. For each question posed, in each rural or urban area, there was only agreement between stakeholders and older people for a maximum of one response. Whereas, when comparing responses from the same participant groups in urban or rural settings, there was a maximum agreement of two responses, with two questions having no agreement in responses at all. Responses across all discussion-areas were mostly categorized within the Societal level, with Individual, Relationship, and Environment featuring less frequently.

CONCLUSION

This study highlights the need for contextually curated interventions to address the concerns of older adults and their caregivers in rural and urban settings. An inclusive and multidimensional approach is needed to conquer the barriers that impede healthy aging, with input from various stakeholders.

Determinants of obesity in Latin America

Obesity rates are increasing almost everywhere in the world, although the pace and timing for this increase differ when populations from developed and developing countries are compared. The sharp and more recent increase in obesity rates in many Latin American countries is an example of that and results from regional characteristics that emerge from interactions between multiple factors. Aware of the complexity of enumerating these factors, we highlight eight main determinants (the physical environment, food exposure, economic and political interest, social inequity, limited access to scientific knowledge, culture, contextual behaviour and genetics) and discuss how they impact obesity rates in Latin American countries. We propose that initiatives aimed at understanding obesity and hampering obesity growth in Latin America should involve multidisciplinary, global approaches that consider these determinants to build more effective public policy and strategies, accounting for regional differences and disease complexity at the individual and systemic levels.

Behavioral public policy in practice: Misconceptions and opportunities

I greatly respect the authors of the target article. However, in contrast to the target article's assertion, practitioners of behavioral public policy are indeed involved in developing and promoting systemic solutions. Its "i-frame"/"s-frame" distinction is incoherent, unhelpful, and obscures promising future directions for behavioral public policy. Its content and presentation undermine its stated goals and encourage sweeping dismissals of the field.

What isn't public health?

By recognizing the structural causes of health and illness, public health has often been associated with values of compassion and solidarity, and a relational understanding of human agency. Rather than supporting the consistent integration and application of these insights, however, public health is now sometimes invoked more as a rhetorical move, used to construct issues as simple questions of neoliberal scientistic rationalism. Public health practitioners must reckon, therefore, with how the field can be discursively deployed in the public square, for multiple divergent political ends. If public health is always positioned as a value-neutral and detached scientific approach to addressing complex subjects, from drug use to pandemics, it not only fails to connect with the arguments of its critics, but further divorces what was once called the public health 'movement' from the strong and progressive political and theoretical positions it was founded upon and should advocate for today.

Impact of short and long exposure to cafeteria diet on food intake and white adipose tissue lipolysis mediated by glucagon-like peptide 1 receptor

Introduction

The modern food environment facilitates excessive calorie intake, a major driver of obesity. Glucagon-like peptide 1 (GLP1) is a neuroendocrine peptide that has been the basis for developing new pharmacotherapies against obesity. The GLP1 receptor (GLP1R) is expressed in central and peripheral tissues, and activation of GLP1R reduces food intake, increases the expression of thermogenic proteins in brown adipose tissue (BAT), and enhances lipolysis in white adipose tissue (WAT). Obesity decreases the efficiency of GLP1R agonists in reducing food intake and body weight. Still, whether palatable food intake before or during the early development of obesity reduces the effects of GLP1R agonists on food intake and adipose tissue metabolism remains undetermined. Further, whether GLP1R expressed in WAT contributes to these effects is unclear.

Methods

Food intake, expression of thermogenic BAT proteins, and WAT lipolysis were measured after central or peripheral administration of Exendin-4 (EX4), a GLP1R agonist, to mice under intermittent-short exposure to CAF diet (3 h/d for 8 days) or a longer-continuous exposure to CAF diet (24 h/d for 15 days). Ex-vivo lipolysis was measured after EX4 exposure to WAT samples from mice fed CAF or control diet for 12 weeks. .

Results

During intermittent-short exposure to CAF diet (3 h/d for 8 days), third ventricle injection (ICV) and intra-peritoneal administration of EX4 reduced palatable food intake. Yet, during a longer-continuous exposure to CAF diet (24 h/d for 15 days), only ICV EX4 administration reduced food intake and body weight. However, this exposure to CAF diet blocked the increase in uncoupling protein 1 (UCP1) caused by ICV EX4 administration in mice fed control diet. Finally, GLP1R expression in WAT was minimal, and EX4 failed to increase lipolysis ex-vivo in WAT tissue samples from mice fed CAF or control diet for 12 weeks. .

Discussion

Exposure to a CAF diet during the early stages of obesity reduces the effects of peripheral and central GLP1R agonists, and WAT does not express a functional GLP1 receptor. These data support that exposure to the obesogenic food environment, without the development or manifestation of obesity, can alter the response to GLP1R agonists. .

Eating contexts determine the efficacy of nutrient warning labels to promote healthy food choices

Introduction

Unhealthy food choices increase the risk of obesity and its co-morbidities. Nutrition labels are a public health policy that aims to drive individuals toward healthier food choices. Chile has been an example of this policy, where mandatory nutrient warning labels (NWL) identify processed foods high in calories and critical nutrients. Eating contexts influence individual food choices, but whether eating contexts also influence how NWL alter the decision process and selection during food choice is unknown.

Methods

In an online mouse-tracking study, participants prompted to health, typical, or unrestricted eating contexts were instructed to choose between pairs of foods in the presence or absence of NWL. Conflict during choices was analyzed using mouse paths and reaction times.

Results

NWL increased conflict during unhealthy food choices and reduced conflict during healthy choices in all contexts. However, the probability that NWL reversed an unhealthy choice was 80% in a healthy, 37% in a typical, and 19% in an unrestricted context. A drift-diffusion model analysis showed the effects of NWL on choice were associated with an increased bias toward healthier foods in the healthy and typical but not in the unrestricted context.

Discussion

These data suggest that the efficacy of NWL to drive healthy food choices increases in a healthy eating context, whereas NWL are less effective in typical or unrestricted eating contexts.

The physiological control of eating: signals, neurons, and networks

During the past 30 yr, investigating the physiology of eating behaviors has generated a truly vast literature. This is fueled in part by a dramatic increase in obesity and its comorbidities that has coincided with an ever increasing sophistication of genetically based manipulations. These techniques have produced results with a remarkable degree of cell specificity, particularly at the cell signaling level, and have played a lead role in advancing the field. However, putting these findings into a brain-wide context that connects physiological signals and neurons to behavior and somatic physiology requires a thorough consideration of neuronal connections: a field that has also seen an extraordinary technological revolution. Our goal is to present a comprehensive and balanced assessment of how physiological signals associated with energy homeostasis interact at many brain levels to control eating behaviors. A major theme is that these signals engage sets of interacting neural networks throughout the brain that are defined by specific neural connections. We begin by discussing some fundamental concepts, including ones that still engender vigorous debate, that provide the necessary frameworks for understanding how the brain controls meal initiation and termination. These include key word definitions, ATP availability as the pivotal regulated variable in energy homeostasis, neuropeptide signaling, homeostatic and hedonic eating, and meal structure. Within this context, we discuss network models of how key regions in the endbrain (or telencephalon), hypothalamus, hindbrain, medulla, vagus nerve, and spinal cord work together with the gastrointestinal tract to enable the complex motor events that permit animals to eat in diverse situations.

Examining the neural correlates of goal priming with the NeuroShop, a novel virtual reality fMRI paradigm

OBJECTIVE

Health goal priming has been shown to stimulate healthy food choices by activating an individual's weight-control goal. The present study combined fMRI with a novel virtual reality food choice task to elucidate the underlying neural mechanisms of health goal priming. Previous research has suggested that the ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) play a role in the incorporation of health considerations into the food choice process. Responses may be more representative for those found in real life when assessed in an environment similar to the actual choice environment. Therefore, the first aim of the study was to explore if a novel virtual reality food choice task is sufficiently sensitive to detect basic valuation processes in food choice. The second aim was to examine whether increased activation in the dlPFC drives the effects of health goal priming.

METHODS

Fifty-six female participants performed an fMRI food choice task embedded in a virtual supermarket environment. They chose between perceived healthy and unhealthy products in a health prime, hedonic prime, and non-food control condition, while activation in brain areas involved in self-control and valuation (vmPFC, dlPFC) was assessed.

RESULTS

There were no differences in relative preference for perceived healthy products over unhealthy products between the conditions. There were also no main effects of prime condition on brain activation in the vmPFC and dPFC during food choice. Across conditions, activation in the vmPFC correlated with the tastiness of the chosen product during food choice.

CONCLUSIONS

Although the study does not provide support for health goal priming triggering neural self-control mechanisms, results did show that virtual reality has potential for a more realistic fMRI food choice paradigm.

Why We Eat Too Much, Have an Easier Time Gaining Than Losing Weight, and Expend Too Little Energy: Suggestions for Counteracting or Mitigating These Problems

The intent of this review is to survey physiological, psychological, and societal obstacles to the control of eating and body weight maintenance and offer some evidence-based solutions. Physiological obstacles are genetic and therefore not amenable to direct abatement. They include an absence of feedback control against gaining weight; a non-homeostatic relationship between motivations to be physically active and weight gain; dependence of hunger and satiation on the volume of food ingested by mouth and processed by the gastrointestinal tract and not on circulating metabolites and putative hunger or satiation hormones. Further, stomach size increases from overeating and binging, and there is difficulty in maintaining weight reductions due to a decline in resting metabolism, increased hunger, and enhanced efficiency of energy storage. Finally, we bear the evolutionary burden of extraordinary human capacity to store body fat. Of the psychological barriers, human craving for palatable food, tendency to overeat in company of others, and gullibility to overeat when offered large portions, can be overcome consciously. The tendency to eat an unnecessary number of meals during the wakeful period can be mitigated by time-restricted feeding to a 6-10 hour period. Social barriers of replacing individual physical work by labor-saving appliances, designing built environments more suitable for car than active transportation; government food macronutrient advice that increases insulin resistance; overabundance of inexpensive food; and profit-driven efforts by the food industry to market energy-dense and nutritionally compromised food are best overcome by informed individual macronutrient choices and appropriate timing of exercise with respect to meals, both of which can decrease insulin resistance. The best defense against overeating, weight gain, and inactivity is the understanding of factors eliciting them and of strategies that can avoid and mitigate them.

Self-weighing among young adults: who weighs themselves and for whom does weighing affect mood? A cross-sectional study of a population-based sample

BACKGROUND

Self-weighing is widespread among young adults and is sometimes recommended by healthcare providers for weight management. The present study aims to deepen our understanding of who is frequently self-weighing among young adults, and to examine for whom self-weighing impacts mood based on weighing frequency and other eating and weight-related characteristics.

METHODS

Survey data were collected from a large population-based sample of young adults (31.1 ± 1.6y) participating in Project EAT-IV (n = 1719). Cross-sectional data were stratified across sex and analyzed with chi-square, t-tests, and linear and logistic regressions controlling for age, ethnicity/race, education level, and income.

RESULTS

Self-weighing frequency was higher among male and female young adults with a current eating disorder, those trying to lose weight or who endorsed any disordered eating behaviors or cognition, and females with higher BMI. Young adult females were significantly more likely than males to report that self-weighing impacted their mood (53% vs 27%, p < 0.05). Among both male and female young adults, there was a higher probability of participants reporting that self-weighing impacted their mood among those who were self-weighing more frequently, had higher BMI, were trying to lose weight, and endorsed disordered eating behaviors or cognitions.

CONCLUSION

Findings suggest that for many young adults, particularly females and those with weight-related concerns, self-weighing is a behavior that comes with emotional valence. The emotional consequences of self-weighing should be considered when making public health and clinical recommendations regarding the usefulness of self-weighing.

Investigating salience strategies to counteract obesity

The investigation of the characteristics and attributes that make a brand prominent for shoppers is known as salience research. This line of study concentrates on influencing buying behaviors via the manipulation of shopping environments and food products. Such promotional strategies successfully attract massive food sales and therefore have been associated with changes in dietary patterns and the epidemic expansion of non-communicable diseases, like obesity. Marketers have empirically proven that global buying patterns are influenced by their salience strategies and techniques. However, despite the significance of such methods, empirical salience investigations have rarely been extended beyond their primary business focus to the field of health promotion. Therefore, this study is presenting a way of transferring the salience knowledge to the health promotion field in order to track dietary choices and possibly gain information to identify buying and eating behaviors connected to obesity. The salience literature from various disciplines permits to hypothesize that consumers are more likely to have unhealthy diets when food-choices and conditions are saliently manipulated. A quasi-experimental method (combining salience measures with Bayesian analysis) was used to test this proposition. The results support the hypothesis and endorse the introduced research tool. As predicted, data reflect the latest national overweight and obesity statistics and suggest that habitual unhealthy diets are more likely when salience strategies link food products to taste, social and emotional attributes. These preliminary findings encourage further investigation to enhance the method as a possible epidemiological tool.

Leptin level as a biomarker of uncontrolled eating in obesity and overweight

BACKGROUND

Uncontrolled eating (UE) showed important relationships with the development of obesity. Homeostatic regulations of feeding and energy balance, as well as hedonic eating, are regulated by leptin.

AIMS

The aims of this study were (1) to assess eating behaviors of Algerian adults as measured by the 51-item eating inventory; we also evaluate changes in the Three-Factor Eating Questionnaire (TFEQ) scores according to the body mass index (BMI) category; (2) to examine the association between the scores of the three TFEQ factors and the BMI values of the participants; and (3) to examine whether leptin concentrations are associated with eating behavior. Our hypothesis is that participants with obesity and high concentrations of leptin might display uncontrolled eating behavior.

METHODS

The subjects were 190 participants (60 obese, 60 overweight, and 70 lean subjects). The eating behavior was measured by using the 51-item eating inventory. Serum insulin concentrations were assessed by radioimmunoassay and were used to calculate homeostasis model assessment (HOMA). Serum leptin was quantified by the enzyme-linked immunosorbent assay (ELISA).

RESULTS

Obese and overweight subjects showed hyperphagic behavior, i.e., uncontrolled eating. The logistic regression analysis showed an effect of leptin, HOMA, uncontrolled eating, and emotional eating on BMI. Leptin levels were associated with the uncontrolled eating and influenced by insulin sensitivity.

CONCLUSIONS

The uncontrolled eating reflects hyperphagic eating behavior in obese and overweight subjects. Coexistence of uncontrolled eating and high level of leptin demonstrates a state of leptin resistance resulting in an inability to detect satiety. High circulating leptin can be considered a potential biomarker of uncontrolled eating.

Obesity and health care interventions: Substantiating a multi-modal challenge through the lens of grounded theory

ISSUE ADDRESSED

One of the biggest concerns for human health in the 21st century is the ever-increasing rate of obesity and its associated budgetary implications for publicly funded health care service provisioning. This study at the outset explores the multifaceted nature of food-related consumption choices and outcomes of obesity, and later offers suggestions to improve the existing interventional strategies to curtail the epidemic.

METHODS

A total of 24 participants were recruited through poster invitations placed around the greater metropolitan area of Auckland, New Zealand. Participants shared their health care intervention program experiences through in-depth, semi-structured interviews. Data were analysed in keeping with traditions of constructivist grounded theory.

FINDINGS

Analysis revealed various concurrent individually acting and ecologically mediated processes which led to obesogenic outcomes as a result of social actors' (participants) engagement in acts of (food-related) consumption practices.

CONCLUSIONS

This study helps to illustrate the underlying, multifaceted processes that lead to obese individuals feeling defeated or disempowered and categorically willing, yet unable to bring about healthy changes in their lives. We hope this study will prompt health care practitioners to take a holistic approach while conceiving and deploying health care intervention programs. SO WHAT?: Current health care interventional programs are not achieving optimum solutions for those in need. All future programs need to acknowledge the roles played by an individual, as well as ecological factors, while deploying client-centric intervention solutions. Perhaps these programs are in need of a team-based approach to offer a truly "wrap-around" service provisioning strategy, rather than the traditional one-on-one consultative approaches in use at current times.

Combating Excessive Eating: A Role for Four Evidence-Based Remedies

OBJECTIVE

The aim of this study is to review the control of energy balance and outline some causes of and remedies for excessive energy intake.

METHODS

A narrative review was conducted.

RESULTS

There is negative feedback control of energy intake and body weight, but, nonetheless, energy intake is only loosely coupled with energy expenditure. Consequently, we are vulnerable to eating in excess of energy requirements. In this context, energy density, portion size, and habitual meal patterns have strong influences on energy intake and, accordingly, can be targeted to reduce energy intake. For example, energy density can be reduced without much affecting food reward (approximately the pleasure gained from eating) because their relationship is such that reward value is affected relatively little by increments in energy density above 1.5 kcal/g. This and other strategies that increase reward per calorie eaten may be superior to increasing the satiety effect of products because fullness is not inherently rewarding. Low-calorie sweeteners provide a means to reduce energy density while largely preserving food or beverage reward value. Consistent with this, consumption of low-calorie sweeteners compared with consumption of sugars has been found to reduce energy intake and body weight.

CONCLUSIONS

Understanding what causes excessive eating also provides insights into how to combat this problem.

Adipose-specific deletion of Kif5b exacerbates obesity and insulin resistance in a mouse model of diet-induced obesity

Recent studies have shown that KIF5B (conventional kinesin heavy chain) mediates glucose transporter type 4 translocation and adiponectin secretion in 3T3-L1 adipocytes, suggesting an involvement of KIF5B in the homeostasis of metabolism. However, the in vivo physiologic function of KIF5B in adipose tissue remains to be determined. In this study, adipose-specific Kif5b knockout (F-K5bKO) mice were generated using the Cre-LoxP strategy. F-K5bKO mice had similar body weights to controls fed on a standard chow diet. However, F-K5bKO mice had hyperlipidemia and significant glucose intolerance and insulin resistance. Deletion of Kif5b aggravated the deleterious impact of a high-fat diet (HFD) on body weight gain, hepatosteatosis, glucose tolerance, and systematic insulin sensitivity. These changes were accompanied by impaired insulin signaling, decreased secretion of adiponectin, and increased serum levels of leptin and proinflammatory adipokines. F-K5bKO mice fed on an HFD exhibited lower energy expenditure and thermogenic dysfunction as a result of whitening of brown adipose due to decreased mitochondria biogenesis and down-regulation of key thermogenic gene expression. In conclusion, selective deletion of Kif5b in adipose tissue exacerbates HFD-induced obesity and its associated metabolic disorders, partly through a decrease in energy expenditure, dysregulation of adipokine secretion, and insulin signaling.-Cui, J., Pang, J., Lin, Y.-J., Gong, H., Wang, Z.-H., Li, Y.-X., Li, J., Wang, Z., Jiang, P., Dai, D.-P., Li, J., Cai, J.-P., Huang, J.-D., Zhang, T.-M. Adipose-specific deletion of Kif5b exacerbates obesity and insulin resistance in a mouse model of diet-induced obesity.

Three-Year Follow-Up of Participants from a Self-Weighing Randomized Controlled Trial

Frequent self-weighing is associated with weight loss maintenance. Several years ago, we investigated frequent self-weighing's effect on weight loss and found the participants lost a significant amount of weight. Three years after this trial's end, participants were contacted for an update on their weight and self-weighing frequency. Weight change and self-weighing frequency since the end of the study were assessed. We hypothesized that participants who maintained frequent self-weighing behavior would have maintained their weight loss. Out of 98 participants enrolled in the RCT, 37% (n = 36) participated in this follow-up study. Total weight loss during the trial for the follow-up participants was 12.7 ± 19.4 lbs (p < 0.001). Three years after intervention, participants regained 0.9 ± 4.34 lbs, a value that was not statistically different from zero (p = 0.75). This did not differ by gender (p = 0.655). Over 75% of these participants continued to weigh themselves at least once a week. Frequent self-weighing may be an effective, low-cost strategy for weight loss maintenance. Future research should further investigate the role of self-weighing in long-term weight gain prevention.

Effect of plate size on meal energy intake in normal weight women

BACKGROUND/OBJECTIVES

Use of smaller plates to control food intake is a commonly recommended strategy for restricting energy intake, despite conflicting results. Therefore, the aim of this study was to examine whether or not three different sizes of plates influence energy intake during a multi-itemed buffet meal in normal weight women.

SUBJECTS/METHODS

This was a cross-over study conducted on 37 female participants aged 19-25 years with normal BMI levels. Participants were recruited from Hacettepe University and the surrounding community. On experimental days, participants ate a standard breakfast and were then randomly assigned to eat lunch using a small (19 cm), medium (23 cm), or large (28 cm) diameter plate. Visual analogue scale (VAS) scores on sensory and satiety outcomes were measured for all meals. Energy and macronutrient intakes during lunch were recorded.

RESULTS

There was no evidence that use of a smaller plate size reduced energy or specific macronutrient intake during the free choice lunch meal. Multiple visits to the serving table were not associated with energy or macronutrient intake. Plate size did not affect VAS scores during the test days.

CONCLUSIONS

Plate size did not influence energy intake, meal composition, or palatability in normal weight women during a multi-itemed open buffet lunch. Studies in natural settings at the population level are needed to clarify current outcomes.

The role of physical activity and exercise in obesity and weight management: Time for critical appraisal

The prevalence of overweight and obesity has increased dramatically during last 3 decades with devastating consequences to public health. Recommended strategies to reduce obesity have focused on healthier diet and physical activity (PA). Clearly, these approaches have not been successful, but whether this is due to failure to restrict energy intake or to maintain high levels of energy expenditure has been the subject of great controversy. Consequently, there has been a great deal of confusion about the role of PA and exercise in obesity and weight management. In this article, the theoretical basis for considering reduced PA and energy expenditure as the cause of obesity is appraised. Further, the role of PA in food intake and weight control is examined. The idea that obesity is caused by consistent decline in daily energy expenditure is not supported either by objective measures of energy expenditure or physiological theory of weight gain alone. However, since voluntary exercise is the most important discretionary component of total daily energy expenditure, it can affect energy balance. Therefore, PA and exercise hold potential as part of the solution for the ongoing obesity epidemic.

Usage and Understanding of Serving Size Information on Food Labels in the United States

Purpose.

To investigate consumer understanding and usage of serving size (SS) information on Nutrition Facts (NF) labels.

Design.

We analyzed three data sources: (1) U.S. Food and Drug Administration (FDA) Health and Diet Survey (HDS) 1994 (n = 1945), 1995 (n = 1001), and 2008 (n = 2584); (2) National Health and Nutrition Examination Survey (NHANES) 2005–2006 and 2007–2008 (n = 10,750); and (3) 2011 FDA Nutrition Facts Label Experimental Study (NFLES) (n = 9493). Data from FDA are cross-sectional and we focused on usage and meaning of SS.

Setting.

United States.

Subjects.

Adults (18+ years).

Measures.

Both HDS and NHANES addressed how often participants used SS information and HDS also asked how SS is determined. Both NHANES and NFLES contained similar questions on the meaning of SS but NFLES also included an open-ended response option.

Analysis.

We included both quantitative and qualitative measures. Questions were analyzed by demographic variables and body mass index with frequencies, cross-tabulations, and χ2 statistics reported.

Results.

HDS showed that the percentage of consumers who used SS information often or sometimes increased from 54% in 1994 to 64% in 2008. NHANES and NFLES data indicated that a majority of respondents had misinterpreted the meaning of SS. Women and obese individuals were more likely to use SS often or sometimes, but were also more likely to misinterpret the meaning of SS. A small subsample of NFLES participants expressed a distrust of the SS information.

Conclusion.

There is a widespread misunderstanding about SS, suggesting the need for clearer NF labels or enhanced education efforts.

Frequent Self-Weighing with Electronic Graphic Feedback to Prevent Age-Related Weight Gain in Young Adults

OBJECTIVE

An intervention using Wi-Fi scales and graphic e-mail feedback, the caloric titration method (CTM), to reduce age-related weight gain over 1 year among college students was evaluated.

METHODS

First-year college students (n = 167) were randomized to CTM or control (C) groups and provided Wi-Fi scales. The CTM group was instructed to weigh daily, view a weight graph e-mailed to them after weighing, and try to maintain their weight. The C group could weigh at any time but did not receive feedback. At 6 months and 1 year, the C group provided weights. For intention to treat analysis, an adjusted mixed model was used to analyze the effect of the intervention.

RESULTS

Baseline body mass index was 22.9 ± 3.0 kg/m(2) . Ninety-five percent of the CTM participants weighed ≥ 3 times/week, compared to 15% in the C group (P < 0.001). After 1 year, the C group had gained 1.1 ± .4 kg whereas the CTM group lost 0.5 ± 3.7 kg (F = 3.39, P = 0.035). The difference in weight change between the two groups at 1 year was significant (P = 0.004). Retention was 81%.

CONCLUSIONS

CTM intervention was effective in preventing age-related weight gain in young adults over 1 year and thus offers promise to reduce overweight and obesity.

Consumer Acceptance of Population-Level Intervention Strategies for Healthy Food Choices: The Role of Perceived Effectiveness and Perceived Fairness

The present study investigates acceptance of intervention strategies for low-calorie snack choices that vary regarding the effect they have on consumers’ freedom of choice (providing information, guiding choice through (dis)incentives, and restricting choice). We examine the mediating effects of perceived effectiveness and perceived fairness, and the moderating effects of barriers to choose low-calorie snacks and perceived responsibility for food choice. Data was collected through an online survey, involving three waves that were completed over a seven week timespan. Information was collected on barriers and perceived responsibility, and evaluations of a total of 128 intervention strategies with varying levels of intrusiveness that were further systematically varied in terms of source, location, approach/avoidance, type, and severity. A total of 1173 respondents completed all three waves. We found that the effect of intervention intrusiveness on acceptance was mediated by the perceived personal- and societal effectiveness, and the perceived fairness of interventions. For barriers and perceived responsibility, only main effects on intervention-specific beliefs were found. Government interventions were accepted less than interventions by food manufacturers. In conclusion, the present study shows that acceptance of interventions depends on perceptions of personal- and societal effectiveness and fairness, thereby providing novel starting points for increasing acceptance of both existing and new food choice interventions.

Self-Weighing: Helpful or Harmful for Psychological Well-Being? A Review of the Literature

Conflicting views as to the helpfulness or harmfulness of self-weighing for the control of body weight have been presented in the fields of obesity and eating disorders. Because self-weighing is increasingly being considered as an intervention to promote weight loss or prevent weight gain, it is timely to consider unintended psychological outcomes and behavioral correlates of this behavior. Twenty articles from the published literature examining self-weighing and psychological outcomes or weight control behaviors were reviewed. In evaluating self-weighing and affect (ten studies), self-esteem (four studies) and body evaluation (ten studies), and eating behaviors/cognitions (13 studies), in total, most studies found a negative relationship between self-weighing and outcomes (affect: 4/10, self-esteem: 3/4, body evaluation: 4/10, eating behaviors/cognitions: 6/13). Themes that emerged included relationships between self-weighing and negative outcomes for women and younger individuals, and lack of a relationship or positive outcomes for overweight, treatment seeking individuals. Though self-weighing has shown promise in aiding weight control, the degree to which weight loss, and not self-weighing, affects psychological outcomes is not clear. Further assessment of psychological outcomes in self-weighing research may be warranted, as this review suggests the potential for adverse effects of self-weighing in some individuals.

Weighing the Evidence of Common Beliefs in Obesity Research

Obesity is a topic on which many views are strongly held in the absence of scientific evidence to support those views, and some views are strongly held despite evidence to contradict those views. We refer to the former as "presumptions" and the latter as "myths." Here, we present nine myths and 10 presumptions surrounding the effects of rapid weight loss; setting realistic goals in weight loss therapy; stage of change or readiness to lose weight; physical education classes; breastfeeding; daily self-weighing; genetic contribution to obesity; the "Freshman 15"; food deserts; regularly eating (versus skipping) breakfast; eating close to bedtime; eating more fruits and vegetables; weight cycling (i.e., yo-yo dieting); snacking; built environment; reducing screen time in childhood obesity; portion size; participation in family mealtime; and drinking water as a means of weight loss. For each of these, we describe the belief and present evidence that the belief is widely held or stated, reasons to support the conjecture that the belief might be true, evidence to directly support or refute the belief, and findings from randomized controlled trials, if available. We conclude with a discussion of the implications of these determinations, conjecture on why so many myths and presumptions exist, and suggestions for limiting the spread of these and other unsubstantiated beliefs about the obesity domain.

Stimuli associated with the cancellation of food and its cues enhance eating but display negative incentive value

Initially neutral conditioned stimuli paired with food often acquire motivating properties, including serving as secondary reinforcers, enhancing instrumental responding in Pavlovian-instrumental transfer procedures, and potentiating food consumption under conditions of food satiation. Interestingly, cues associated with the cancellation of food and food cues may also potentiate food consumption (e.g., Galarce and Holland, 2009), despite their apparent negative correlations with food delivery. In three experiments with rats, we investigated conditions under which potentiation of feeding by such "interruption stimuIi" (ISs) develops, and some aspects of the content of that learning. Although in all three experiments ISs enhanced food consumption beyond control levels, they were found to act as conditioned inhibitors for anticipatory food cup entry (Experiment 1), to serve as conditioned punishers of instrumental responding (Experiment 2), and to suppress instrumental lever press responding in a Pavlovian instrumental transfer procedure (Experiment 3). Furthermore, when given concurrent choice between different foods, an IS enhanced consumption of the food whose interruption it had previously signaled, but when given a choice between performing two instrumental responses, the IS shifted rats' choice away from the response that had previously yielded the food whose interruption had been signaled by IS (Experiment 3). Thus, the effects of an IS on appetitive responses were opposite to its effects on consummatory responding. Implications for our understanding of learned incentive motivation and the control of overeating are discussed.

"It's a balance of just getting things right": mothers' views about pre-school childhood obesity and obesity prevention in Scotland

Background

The high prevalence of childhood obesity is a concern for policy makers and health professionals, leading to a focus on early prevention. The beliefs and perspectives of parents about early childhood obesity, and their views and opinions about the need for weight management interventions for this age group are poorly understood.

Methods

A formative qualitative focus group study with parents of pre-school children took place in eight community-based locations throughout North-East Scotland to explore their ideas about the causes of early childhood obesity, personal experiences of effective weight management strategies, and views about the format and content of a possible child-orientated weight management programme. Study participants were recruited via pre-school nurseries.

Results

Thirty-four mothers (median age 37 years) took part in the study, but only two believed their child had a weight problem. Participants (who focussed primarily on dietary issues) expressed a strong sense of personal responsibility to ‘get the balance right’ regarding their child’s weight, and were generally resistant to the idea of attending a weight management programme aimed at very young children. At the same time, they described a range of challenges to their weight management intentions. These included dealing with intrinsic uncertainties such as knowing when to stop ‘demand feeding’ for weight gain, and judging appropriate portion sizes - for themselves and their children. In addition they faced a range of extrinsic challenges associated with complex family life, i.e. catering to differing family members dietary needs, food preferences, practices and values, and keeping their ‘family food rules’ (associated with weight management) when tired or pressed for time.

Conclusions

The findings have important implications for health professionals and policy makers wishing to engage with parents on this issue, or who are currently developing ‘family-centred’ early childhood weight management interventions. The challenge lies in the fact that mothers believe themselves to be the primary (and capable) agents of obesity prevention in the early years – but, who are at the same time, attempting to deal with many mixed and conflicting messages and pressures emanating from their social and cultural environments that may be undermining their weight management intentions.

Role of amygdala central nucleus in the potentiation of consuming and instrumental lever-pressing for sucrose by cues for the presentation or interruption of sucrose delivery in rats

Initially neutral conditioned stimuli (CSs) paired with food often acquire motivating properties. For example, CS presentations may enhance the rate of instrumental responding that normally earns that food reward (Pavlovian-instrumental transfer), or potentiate consumption of that food when the animal is food-sated. Recent evidence suggests that cues associated with the withdrawal of food and food cues (interruption stimuli or ISs) may also potentiate feeding, despite exhibiting some characteristics of conditioned inhibition. Here, we compared the ability of CSs and ISs to modulate both eating food and working for it. If CSs and ISs potentiate eating food by controlling a similar incentive state, both types of cues might also be expected to enhance instrumental responding for food. Although we found substantial potentiation of feeding by both CSs and ISs, and powerful enhancement of instrumental responding by a CS, we found no evidence for such instrumental enhancement by an IS. Furthermore, although an IS produced more FOS expression in the amygdala central nucleus (CeA) than either a previously reinforced CS or a control stimulus after a test for potentiated feeding, an intact CeA was unnecessary for potentiation of feeding by either a CS or an IS. Nevertheless, as in previous studies, CeA was critical to the ability of a CS to enhance instrumental responding. Implications for understanding the nature and basis for incentive learning are discussed.

Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity

The chemokine receptor CXCR4 is expressed on adipocytes and macrophages in adipose tissue, but its role in this tissue remains unknown. We evaluated whether deficiency in either adipocyte or myeloid leukocyte CXCR4 affects body weight (BW) and adiposity in a mouse model of high-fat-diet (HFD)-induced obesity. We found that ablation of adipocyte, but not myeloid leukocyte, CXCR4 exacerbated obesity. The HFD-fed adipocyte-specific CXCR4-knockout (AdCXCR4ko) mice, compared to wild-type C57BL/6 control mice, had increased BW (average: 52.0 g vs. 35.5 g), adiposity (average: 49.3 vs. 21.0% of total BW), and inflammatory leukocyte content in white adipose tissue (WAT), despite comparable food intake. As previously reported, HFD feeding increased uncoupling protein 1 (UCP1) expression (fold increase: 3.5) in brown adipose tissue (BAT) of the C57BL/6 control mice. However, no HFD-induced increase in UCP1 expression was observed in the AdCXCR4ko mice, which were cold sensitive. Thus, our study suggests that adipocyte CXCR4 limits development of obesity by preventing excessive inflammatory cell recruitment into WAT and by supporting thermogenic activity of BAT. Since CXCR4 is conserved between mouse and human, the newfound role of CXCR4 in mouse adipose tissue may parallel the role of this chemokine receptor in human adipose tissue.

Using health primes to reduce unhealthy snack purchases among overweight consumers in a grocery store

OBJECTIVE

Healthy-eating intentions of overweight individuals are often thwarted by the presence of attractive food temptations in grocery stores and the home environment. To support healthy-eating intentions, we tested the effectiveness of a simple health prime to reduce the purchases of energy-dense snack foods in a grocery store among overweight individuals.

DESIGN

This field experiment had a 2 (condition: health prime vs control) × 2 (weight status: overweight vs normal weight) between-participants design.

METHOD

Customers of a grocery store were handed a recipe flyer that either contained a health and diet prime, or not. Participants' weight and height, as well as their attention to and awareness of the prime during shopping, were assessed by means of a questionnaire. The purchase of unhealthy snack foods was assessed by means of the receipt.

RESULTS

Results showed that the health prime reduced snack purchases compared with the control condition among overweight and obese participants. When primed, overweight and obese participants bought almost 75% fewer snacks than when not primed. Additional analyses showed that although the prime worked only when customers paid initial attention to the flyer that contained the health prime, no conscious awareness of the prime during grocery shopping was necessary for these effects.

CONCLUSION

These findings suggest that health priming can lead to healthier grocery shopping among overweight consumers, without relying on conscious awareness during shopping. This makes priming a highly viable intervention tool to facilitate healthy food choices. Such tools are especially relevant in the setting of grocery shopping, given that they have direct effects on eating in the home environment and thus for longer-term weight management.

The Role of Registered Dietitians: In Health Promotion

We used our experience assisting in the development of and evaluating the Alberta Nutrition Guidelines for Children and Youth (ANGCY) as a basis for exploring roles that registered dietitians (RDs) can play within health promotion, and how others perceive the RD role. Data were generated via 12 key informant interviews and observations during a multiple case study of recreation facilities that had and had not adopted the ANGCY. We also drew on dialogue and personal observations during development of the ANGCY. Dietitians working in government, academia, community settings, private practice, and industry played an important role throughout the development and implementation of the ANGCY. Some sectors proactively sought RD expertise, while others with less ability to pay accessed RDs’ services less. Informants generally regarded RDs in a positive light. Findings indicate the profession should incrementally adjust training models to reflect emerging areas of practice, and highlight the need for RDs to proactively seek new avenues in which to apply their skills. These actions will help RDs remain the trusted source of food and nutrition information, not only in health care, but also within health promotion settings.

Food-induced brain responses and eating behaviour

The brain governs food intake behaviour by integrating many different internal and external state and trait-related signals. Understanding how the decisions to start and to stop eating are made is crucial to our understanding of (maladaptive patterns of) eating behaviour. Here, we aim to (1) review the current state of the field of 'nutritional neuroscience' with a focus on the interplay between food-induced brain responses and eating behaviour and (2) highlight research needs and techniques that could be used to address these. The brain responses associated with sensory stimulation (sight, olfaction and taste), gastric distension, gut hormone administration and food consumption are the subject of increasing investigation. Nevertheless, only few studies have examined relations between brain responses and eating behaviour. However, the neural circuits underlying eating behaviour are to a large extent generic, including reward, self-control, learning and decision-making circuitry. These limbic and prefrontal circuits interact with the hypothalamus, a key homeostatic area. Target areas for further elucidating the regulation of food intake are: (eating) habit and food preference formation and modification, the neural correlates of self-control, nutrient sensing and dietary learning, and the regulation of body adiposity. Moreover, to foster significant progress, data from multiple studies need to be integrated. This requires standardisation of (neuroimaging) measures, data sharing and the application and development of existing advanced analysis and modelling techniques to nutritional neuroscience data. In the next 20 years, nutritional neuroscience will have to prove its potential for providing insights that can be used to tackle detrimental eating behaviour.

Dietary (sensory) variety and energy balance

The prevalence of overweight and obesity in US adults is currently 68%, compared with about 47% in the early 1970s. Many dietary factors have been proposed to contribute to the US obesity epidemic, including the percentage of energy intake from fat, carbohydrate and protein; glycemic index; fruit and vegetable intake; caloric beverage intake; and fast food or other restaurant food intake. One factor that may also be important is the variety of foods in the diet having different sensory properties, that is, flavors, textures, shapes and colors. A host of studies show that when presented with a greater variety of foods within a meal, humans consume about 22% more energy compared to when only one food is available. These data are supported by laboratory animal studies on the effects of sensory variety on consumption as well as body weight and fat gain. Longer term experimental trials in humans lasting 1-2wk had mixed results but generally showed an increase in intake of 50-60kcal/d per additional food offered, provided at least 5 different foods per day were available. In only two studies to date has reducing dietary variety been explored as a potential method for weight loss. In those studies, which also incorporated a standard behavioral weight loss approach, there was no difference in weight loss when either snack food variety or low nutrient dense, high energy dense variety was limited. However, a broader treatment approach may be more effective, for example limiting the excess variety of foods high in energy density yet which provide little benefit to vitamin and mineral intake at each meal, and further studies are needed in this area.

Set points, settling points and some alternative models: theoretical options to understand how genes and environments combine to regulate body adiposity

The close correspondence between energy intake and expenditure over prolonged time periods, coupled with an apparent protection of the level of body adiposity in the face of perturbations of energy balance, has led to the idea that body fatness is regulated via mechanisms that control intake and energy expenditure. Two models have dominated the discussion of how this regulation might take place. The set point model is rooted in physiology, genetics and molecular biology, and suggests that there is an active feedback mechanism linking adipose tissue (stored energy) to intake and expenditure via a set point, presumably encoded in the brain. This model is consistent with many of the biological aspects of energy balance, but struggles to explain the many significant environmental and social influences on obesity, food intake and physical activity. More importantly, the set point model does not effectively explain the 'obesity epidemic'--the large increase in body weight and adiposity of a large proportion of individuals in many countries since the 1980s. An alternative model, called the settling point model, is based on the idea that there is passive feedback between the size of the body stores and aspects of expenditure. This model accommodates many of the social and environmental characteristics of energy balance, but struggles to explain some of the biological and genetic aspects. The shortcomings of these two models reflect their failure to address the gene-by-environment interactions that dominate the regulation of body weight. We discuss two additional models--the general intake model and the dual intervention point model--that address this issue and might offer better ways to understand how body fatness is controlled.