Traditional food marketing stimulates adolescents' consumption of energy-dense, nutrient-poor foods. These dietary behaviours may track into adulthood and lead to weight gain, obesity and related non-communicable diseases. While social media use in adolescents has proliferated, little is known about the content of food marketing within these platforms, and how this impacts adolescents' dietary behaviours. This paper aimed to obtain expert insights on factors involved in the association between social media food marketing (SMFM) and adolescent dietary behaviours, and to explore their views on key priorities, challenges and strategies for future SMFM research and policies. One-on-one semi-structured interviews (n = 17) were conducted with experts from Western Europe, Australia and North America, in the fields of public health (policy), nutrition science, social media marketing, adolescent medicine, clinical psychology, behavioural sciences, communication, food industry, social influencing, and social marketing. The experts' collective responses identified that the line between food content posted by social media users and food companies is blurred. Adolescents' processing of SMFM may be mostly implicit, involving social comparison, emotional engagement, and attaching symbolic meanings to foods. Mediating factors and adolescent-specific and SMFM-specific moderating factors potentially influencing adolescents' response to SMFM were summarized in a Social Ecological model. Experts agreed that there is limited scientific evidence on adolescent-targeted SMFM and there are no strict regulations in place to protect adolescents from unhealthy SMFM, while adolescents are active social media users who are cognitively vulnerable to implicit marketing tactics. Adolescent-targeted SMFM should be controlled by encouraging healthy food marketing or limiting junk food marketing. Also, prioritizing both quantitative research on SMFM exposure and its impact, and qualitative research to obtain adolescents¿ perspectives, is crucial to advocate for regulatory changes regarding adolescent-targeted SMFM content.

Objectives: In order to manage blood glucose levels in pregnancy, women need to know what and how much to eat, particularly for foods containing carbohydrate. The aim was to assess pregnant women¿s carbohydrate and standard serve size knowledge and examine whether health professionals provided nutrition education. Methods: Between July 2017 and April 2018 Australian pregnant women were recruited to complete an online survey, including a modified PedCarbQuiz carbohydrate knowledge questionnaire and an online buffet, where they selected images equivalent to one Australian Guide to Healthy Eating (AGHE) standard serve size. Results: 186 pregnant women (mean age 30.9¿years, SD = 4.7¿years) 12¿22¿weeks gestation completed the survey. Participants achieved a median score of 27/36 for identification of carbohydrate-containing foods and a median score of 1/12 (range 0¿11) for identification of grams of carbohydrate in specific portions. Participants achieved a median score of 14/22 (range 4¿19) for identification of one AGHE standard serve of 11 carbohydrate-containing foods. Less than half (n = 92, 49.5%) received nutrition education from health professionals. Conclusions for Practice: Pregnant women had sub-optimal carbohydrate knowledge. This could contribute to impaired blood glucose concentrations and risk of adverse health outcomes in pregnancy. Opportunities for pregnant women to access nutrition advice from health professionals should be explored.

Issue addressed: The dietary intakes of Australian children are not optimal, with few meeting recommended vegetable and fruit intake targets. Nutrition education in childhood is important for developing healthy eating patterns, with schools an ideal setting for a wide reach. The aims of this study were to examine nutrition education within the NSW primary school syllabus, explore how much time teachers spend teaching nutrition, what is taught, what materials are used, and to identify attitudes towards nutrition education. Method: An online survey consisting of 29 closed questions (with options for comments) was specifically developed for the purpose of this study. Teachers currently teaching at a NSW primary school were eligible to participate. Results: A total of 33 NSW primary school teachers completed the survey. Results indicate that limited time is spent on teaching nutrition with some important nutrition education components currently missed, resources perceived to be inadequate and lack of time reported as the largest barrier to teaching nutrition. Conclusion: In order to improve the quality of nutrition education in NSW primary schools, several important topics need to be integrated into the curriculum, and time constraints of teachers should be taken into account. So what?: Findings from the current survey will inform the development of future nutrition education programs and resources with the aim of integrating nutrition education within the primary school curriculum.

Guidance for food consumption and portion control plays an important role in the global management of overweight and obesity. Carefully conceptualised serving size labelling can contribute to this guidance. However, little is known about the relationship between the information that is provided regarding serving sizes on food packages and levels of actual food consumption. The aim of this systematic review was to investigate how serving size information on food packages influences food consumption. We conducted a systematic review of the evidence published between 1980 and March 2018. Two reviewers screened titles and abstracts for relevance and assessed relevant articles for eligibility in full-text. Five studies were considered eligible for the systematic review. In three of the included studies, changes in serving size labelling resulted in positive health implications for consumers, whereby less discretionary foods were consumed, if serving sizes were smaller or if serving size information was provided alongside contextual information referring to the entire package. One study did not find significant differences between the conditions they tested and one study suggested a potentially negative impact, if the serving size was reduced. The influence of labelled serving size on consumption of non-discretionary foods remains unclear, which is partially due to the absence of studies specifically focusing on non-discretionary food groups. Studies that investigate the impact of serving size labels within the home environment and across a broad demographic cross-section are required.

Objective To develop and validate a brief scale to assess knowledge about the energy content of meals for adults in Switzerland. Methods Based on a random sample, the scale was developed using a Rasch model approach. To assess validity and reliability, the model was replicated and scores were compared with another nutrition knowledge measure and with dietitian trainees¿ scores. A test-retest was performed. Results Survey studies included 477, 505, and 136 participants from the general population and 59 dietician trainees. The Rasch scale consisted of 11 multiple-choice items ranging from easy to difficult and correlated with general nutrition knowledge (r¿=¿.47; P¿<¿.001; r2¿=¿.22). Dietitian trainees achieved higher scores (P¿<¿.001; d¿=¿2.17) than did people from the general population; test-retest reliability results were r¿=¿.73, P¿<¿.001, and r2¿=¿.53. Conclusions and Implications Results showed that the scale is efficient, valid, and reliable for use in the general population in Switzerland.

Issue addressed Portion size guidance strategies have been suggested as an important component of weight management; therefore, the Health Star Rating (HSR) front-of-pack labels could influence consumers' portion-size decisions. However, this has not been investigated to date. This study aims to evaluate whether presenting energy content information and HSRs influences portion size self-selection of specific foods and meals. Methods Adults were randomly assigned to one of three experimental groups in this randomised controlled experiment. Each participant was given either a kJ/100g food label or a HSR label, or was given no information on nutrient composition. They were then asked to serve themselves an adequate portion of breakfast cereal (Kellogg's Nutri-Grain), fruit salad and chocolate, plus a three-component meal (chicken, fries and mixed vegetables). Portion serves and meal weights were compared between each experimental group using ANOVA and the discretionary foods were also compared with the Australian Guide to Healthy Eating (AGHE). Results Neither the kilojoule nor HSR information influenced the self-served portion size of foods or meal components. Mean self-served portion size of the discretionary foods were significantly greater than the standard serving sizes as specified in the AGHE. Conclusion Although food labels have the potential to assist consumers in making product choices, this study indicates that presenting nutrition information does not affect portion size decisions in young adults. So what? Strategies that assist consumers to choose appropriate portion sizes should be developed as a weight management tool.

An online experiment with 536 participants was conducted to investigate how people who differ in body weight perceive scientific information on body weight and mortality. The results showed that individuals who were aware that they are overweight were more inclined to trust a study that showed that overweight reduces mortality (P < 0.001). This finding is relevant as the BMI-mortality association remains a matter of scientific and public debate and people's risk perceptions influences their willingness to change behaviour.

Background/Objectives:As a high-quality diet is associated with a lower risk for several diseases and all-cause mortality, current nutrition education tools provide people with information regarding how to build a healthy and a balanced meal. To assess this basic nutrition knowledge, the research aim was to develop and validate a brief scale to measure the Practical Knowledge about Balanced meals (PKB-7).Subjects/Methods:A pool of 25 items was pretested with experts and laypeople before being tested on a random sample in Switzerland (n=517). For item selection, a Rasch model analysis was applied. The validity and reliability of the new scale were assessed by three additional studies including laypeople (n=597; n=145) and nutrition experts (n=59).Results:The final scale consists of seven multiple-choice items, which met the assumptions of the Rasch model. The validity of the new scale was shown by several aspects: the Rasch model was replicated in a second study, and nutrition experts achieved significantly higher scores than laypeople (t(148)=20.27, P<0.001, d=1.78). In addition, the PKB-7 scale was correlated with other nutrition-related constructs and associated with reported vegetable consumption. Test-retest reliability (r=0.68, P<0.001) was acceptable.Conclusions:The PKB-7 scale is a reliable and a valid Rasch-based instrument in Swiss citizens aged between 18 and 80 years for measuring the practical knowledge about balanced meals based on current dietary guidelines. This brief and easy-to-use scale is intended for application in both research and practice.

Nudging or 'choice architecture' refers to strategic changes in the environment that are anticipated to alter people's behaviour in a predictable way, without forbidding any options or significantly changing their economic incentives. Nudging strategies may be used to promote healthy eating behaviour. However, to date, the scientific evidence has not been systematically reviewed to enable practitioners and policymakers to implement, or argue for the implementation of, specific measures to support nudging strategies. This systematic review investigated the effect of positional changes of food placement on food choice. In total, seven scientific databases were searched using relevant keywords to identify interventions that manipulated food position (proximity or order) to generate a change in food selection, sales or consumption, among normal-weight or overweight individuals across any age group. From 2576 identified articles, fifteen articles comprising eighteen studies met our inclusion criteria. This review has identified that manipulation of food product order or proximity can influence food choice. Such approaches offer promise in terms of impacting on consumer behaviour. However, there is a need for high-quality studies that quantify the magnitude of positional effects on food choice in conjunction with measuring the impact on food intake, particularly in the longer term. Future studies should use outcome measures such as change in grams of food consumed or energy intake to quantify the impact on dietary intake and potential impacts on nutrition-related health. Research is also needed to evaluate potential compensatory behaviours secondary to such interventions.

Little is known about laypeople's practical understanding of a healthy diet, although this is important to successfully promote healthy eating. The present study is the first to experimentally examine how consumers define healthy and balanced food choices for an entire day compared with normal choices and compared with dietary guidelines. We used an extensive fake food buffet (FFB) with 179 foods commonly consumed in the Swiss diet. The FFB is a validated method to investigate food choice behaviour in a well-controlled laboratory setting. People from the general population in Switzerland (n 187; 51·9 % females), aged between 18 and 65 years, were randomly assigned to one of two conditions. In the control group, the participants were instructed to serve themselves foods they would eat on a normal day, whereas in the 'healthy' group they were instructed to choose foods representing a healthy diet. Participants chose significantly more healthy foods, with 4·5 g more dietary fibre, 2 % more protein and 2 % less SFA in the 'healthy' group compared with the control group. However, in both experimental conditions, participants served themselves foods containing twice as much sugar and salt than recommended by dietary guidelines. The results suggest that laypeople lack knowledge about the recommended portion sizes and the amounts of critical nutrients in processed food, which has important implications for communicating dietary guidelines. Furthermore, the energy of the food served was substantially correlated with the energy needs of the participants, demonstrating the potential of the fake food buffet method.

Changes in snacking habits in developed countries are a growing cause for concern, since foods and beverages commonly consumed as snacks, tend to be both energy dense and nutrient poor. Adolescents are characterised by frequent snack consumption. Therefore, promoting more healthful snack choices to adolescents is important for optimising nutrient intake and lowering the risk of chronic disease.The ability to evaluate the healthiness of snacks is essential to making healthy choices. Previous research has shown that health claims can influence consumers' perceptions of food products. However, little is yet known about consumers' perceptions of how nutritious or healthy specific foods or beverages are. This knowledge is important for planning successful interventions and designing healthy snacks that will also appeal to population groups with a higher dietary risk, including adolescents.The aim was to investigate how adolescents evaluate the healthiness of snacks currently available for consumption in school environments. Seventy-five adolescents participated in a sorting task and evaluated the healthiness of 37 representative snacks.The data were analysed using hierarchical multiple regression and cluster analysis. The sugar (ß = -.51, P < .001), fruit (ß = .49, P < .001), total fat (ß = -.41, P = .002) and nut content (ß = .35, P = .002) were significant predictors of snacks' perceived healthiness.The findings of this study are important for tailoring future interventions to promote healthy eating and setting priorities for nutrition education.

Issues addressed It is not known whether individuals can accurately estimate the portion size of foods usually consumed relative to standard serving sizes in national food selection guides. The aim of the present cross-sectional pilot study was to quantify what adults and children deem a typical portion for a variety of foods and compare these with the serving sizes specified in the Australian Guide to Healthy Eating (AGHE). Methods Adults and children were independently asked to serve out their typical portion of 10 common foods (rice, pasta, breakfast cereal, chocolate, confectionary, ice cream, meat, vegetables, soft drink and milk). They were also asked to serve what they perceived a small, medium and large portion of each food to be. Each portion was weighed and recorded by an assessor and compared with the standard AGHE serving sizes. Results Twenty-one individuals (nine mothers, one father, 11 children) participated in the study. There was a large degree of variability in portion sizes measured out by both parents and children, with means exceeding the standard AGHE serving size for all items, except for soft drink and milk, where mean portion sizes were less than the AGHE serving size. The greatest mean overestimations were for pasta (155%; mean 116 g; range 94-139g) and chocolate (151%; mean 38 g; range 25-50g), each of which represented approximately 1.5 standard AGHE servings. Conclusion The findings of the present study indicate that there is variability between parents' and children's estimation of typical portion sizes compared with national recommendations. So what? Dietary interventions to improve individuals' dietary patterns should target education regarding portion size.