Informing a roadmap for cross-sectoral collaboration on portion size management as a national strategy to improve population nutrition - a Delphi study.

BACKGROUND: Addressing food portion sizes is a key untapped opportunity to help tackle obesity. This study sought to inform the agenda of a national movement involving diverse sectors to manage portion sizes in packaged foods, restaurants, cafeterias and prepared foods in grocery stores. METHODS: A Delphi study was conducted with representatives from public health, private-sector food companies and academia that formed a panel of experts (n = 32). Three iterative rounds of surveys were administered over 3 months. The surveys gathered opinions on psychological mindsets affecting portion size choice, eating habits, portion perception and distortion, passive overconsumption and challenges and advantages of this tool to improve population nutrition. The survey also inquired about visions for a future food environment. After every round, responses were analysed and questions narrowed to reach group consensus on specific items in the subsequent round. RESULTS: Although many experts fear that portion size interventions might be perceived as paternalistic, 91% of respondents agreed stealth interventions were preferable. Seventy-three per cent of experts believed that the most impactful portion size intervention was product reformulation while smaller packages were the most effective intervention according to only 28% of experts. The majority of the panel (59%) also believed that creating an artificial stopping point in packages was the best strategy to reduce food consumption. Finally, the study found that one of the most complex aspects of establishing a multi-sector collaboration for obesity prevention was to ascertain trust in the private sector's ability to balance profit versus social responsibility.[Corrections added on 21 March 2019, after first online publication: The percentage of experts who believed that small packages were the most effective intervention has been changed from "16%" to "28%".]. CONCLUSION: This study informs the agenda of a cross-sectoral, coordinated movement to tackle obesity through a combination of changing social norms, individual behaviours and industry practices around portion size. Although cross-sectoral collaboration for non-communicable disease prevention is encouraged by different organizations, strategic efforts to define a common agenda on portion size have been limited thus far. This research highlights important strategies in portion size interventions and steps needed for the success of such a movement, as part of a wider effort across sectors and stakeholders to halt and reverse obesity rates in the USA.

Obesity trend in the United States and economic intervention options to change it: A simulation study linking ecological epidemiology and system dynamics modeling.

OBJECTIVES: To study the country-level dynamics and influences between population weight status and socio-economic distribution (employment status and family income) in the US and to project the potential impacts of socio-economic-based intervention options on obesity prevalence. STUDY DESIGN: Ecological study and simulation. METHODS: Using the longitudinal data from the 2001-2011 Medical Expenditure Panel Survey (N = 88,453 adults), we built and calibrated a system dynamics model (SDM) capturing the feedback loops between body weight status and socio-economic status distribution and simulated the effects of employment- and income-based intervention options. RESULTS: The SDM-based simulation projected rising overweight/obesity prevalence in the US in the future. Improving people's income from lower to middle-income group would help control the rising prevalence, while only creating jobs for the unemployed did not show such effect. CONCLUSIONS: Improving people from low- to middle-income levels may be effective, instead of solely improving reemployment rate, in curbing the rising obesity trend in the US adult population. This study indicates the value of the SDM as a virtual laboratory to evaluate complex distributive phenomena of the interplay between population health and economy.

Simulation models of obesity: a review of the literature and implications for research and policy.

Simulation models (SMs) combine information from a variety of sources to provide a useful tool for examining how the effects of obesity unfold over time and impact population health. SMs can aid in the understanding of the complex interaction of the drivers of diet and activity and their relation to health outcomes. As emphasized in a recently released report of the Institute or Medicine, SMs can be especially useful for considering the potential impact of an array of policies that will be required to tackle the obesity problem. The purpose of this paper is to present an overview of existing SMs for obesity. First, a background section introduces the different types of models, explains how models are constructed, shows the utility of SMs and discusses their strengths and weaknesses. Using these typologies, we then briefly review extant obesity SMs. We categorize these models according to their focus: health and economic outcomes, trends in obesity as a function of past trends, physiologically based behavioural models, environmental contributors to obesity and policy interventions. Finally, we suggest directions for future research.

Telomere length in relation to insulin resistance, inflammation and obesity among Arab youth.

AIM: The aim of this study was to determine the associations of telomere length to markers of obesity, insulin resistance and inflammation in Saudi children. METHODS: A total of 69 boys and 79 girls, aged 5-12 years, participated in this cross-sectional study. Anthropometrics were measured. Serum glucose and lipid profile were measured using routine laboratory methods. Serum insulin, leptin, adiponectin, resistin, tumour necrosis factor-alpha and active plasminogen activator inhibitor 1 were quantified using customized multiplex assay kits. C-reactive protein and angiotensin II were quantified using ELISA. Leucocyte telomere length was examined by quantitative real time PCR utilizing IQ cycler. RESULTS: Mean telomere length was significantly shorter in obese boys compared with their lean counterparts (p = 0.049), not in girls. It was not associated to insulin resistance, adipocytokines and markers of inflammation. In girls, the significant predictor of telomere length was waist circumference, explaining 24% of variance (p = 0.041) while in boys, systolic blood pressure explained 84% of the variance (p = 0.01). CONCLUSION: Childhood obesity in boys corresponds to shorter leucocyte telomere length which is not evident in girls. The association of leucocyte telomere length to blood pressure and waist circumference in children suggests clinical implications as to the contribution of these parameters in premature ageing.

Eating patterns and dietary composition in relation to BMI in younger and older adults.

OBJECTIVE: To compare relative associations of eating patterns and dietary composition with body mass index (BMI) in younger (aged 20-59 years, n=1792) and older (aged 60-90 years, n=893) participants in the Continuing Survey of Food Intakes by Individuals, collected 1994-1996. METHODS: Data from two 24-h dietary recalls from individuals reporting physiologically plausible energy intake (within +/-22% of predicted energy requirements, based on previously published methods) were used. RESULTS: Mean reported energy intake was 96 and 95% of predicted energy requirements in younger and older subjects, respectively. Older subjects were less likely than younger subjects to skip a meal, but snacking was common in both age groups. Fiber density was significantly higher in the older group. A higher BMI in both age groups was associated with a higher total daily energy intake, and higher energy intakes at all eating occasions. In both age groups, eating frequency was positively associated with energy intake, and eating more than three times a day was associated with being overweight or obese. In the younger group but not the older group, a lower fiber density coupled with higher percentage of energy from fat was independently associated with having a higher BMI. CONCLUSIONS: While no one eating occasion contributes more than any other to excess adiposity, eating more often than three times a day may play a role in overweight and obesity in both younger and older persons. A reduced satiety response to dietary fiber in addition to lower energy expenditure may potentially further contribute to weight gain in older persons.