Obesity-related behaviors, such as intake of snacks and sweetened beverages (SSB), are assumed to result from the interplay between environmental factors and adolescents' ability to self-regulate their eating behaviors. The empirical evidence supporting this assumption is missing. This study investigated the relationships between perceptions of at-home and out-of-home food environment (including SSB accessibility, parental, and peers' social pressure to reduce intake of SSB), nutrition self-regulatory strategies (controlling temptations and suppression), and SSB intake. In particular, we hypothesized that these associations would differ across the stages of preadolescence, early and mid-adolescence. Self-reported data were collected from 2,764 adolescents (10-17 years old; 49 % girls) from 24 schools in the Netherlands, Poland, Portugal, and the United Kingdom. Path analysis indicated that direct associations between peers' social influence and SSB intake increased with age. Direct negative associations between at-home and out-of-home accessibility and SSB intake as well as direct positive associations between parental pressure and intake become significantly weaker with age. Accessibility was related negatively to self-regulation, whereas higher social pressure was associated with higher self-regulation. The effects of the environmental factors were mediated by self-regulation. Quantitative and qualitative differences in self-regulation were observed across the stages of adolescence. The associations between the use of self-regulatory strategies and lower SSB intake become significantly stronger with age. In preadolescence, SSB intake was regulated by means of strategies that aimed at direct actions toward tempting food. In contrast, early and mid-adolescents controlled their SSB intake by means of a combination of self-regulatory strategies focusing on direct actions toward tempting food and strategies focusing on changing the psychological meaning of tempting food.

Eating habits are formed from the early childhood through experience gained from the contact with foods and as a result of observation of the environment. One of the feeding disorders, specific for the childhood, is food neophobia, defined as an attitude towards food, which manifests as a persistent reluctance to eat new foods, avoiding tasting unknown products and unwillingness to accept newly introduced flavours or unknown consistency of food. It should be differentiated from pickiness, which are a typical stage of children's development. Food neophobia is a significant problem from both psychological and dietary perspective. The mechanism conditioning the onset of food neophobia has not been fully understood. It can be determined by the combination of biological, psychological and environmental factors, which include: various genetic conditions, individual personality predispositions, the level of child's familiarity with the taste, the moment and the method of introducing new products and parents' attitude towards food. The health consequences of food neophobia refer mainly to the potential loss of benefits due to an imbalanced diet and reducing the consumption of products rich in valuable nutrients. The severity of food neophobia determines the way of feeding children, forming their eating habits for further life.

IntroductionDigital behavioural weight loss interventions have the potential to improve public health; however, these interventions are often not adequately tailored to the needs of the participants. This is the protocol for a trial that aims to determine the effectiveness and cost-effectiveness of the Choosing Health programme as a means to promote weight loss and weight loss maintenance among overweight/obese adults.Methods and analysisThe proposed study is a two-group randomised controlled trial with a nested interrupted time series (ITS) within-person design. Participants (n=285) will be randomly assigned to either the Choosing Health digital intervention or a control group. For intervention participants, ecological momentary assessment will be used to identify behavioural determinants for each individual in order to tailor evidence-based behaviour change techniques and intervention content.Control group participants will receive non-tailored weight loss advice via e-book and generic emails. The primary outcome is the mean difference in weight loss between groups at 6 months controlled for baseline. Secondary outcomes include blood pressure and percentage of body fat; self-reported measures of physical activity, sitting time, quality of life, cost and theory-derived correlates of weight loss. Secondary outcomes will be measured at baseline, 3, 6 and 12 months. The primary outcome for ITS will be daily weight loss plan adherence. Data will be analysed using regression and time series analyses.Ethics and disseminationEthics approval was granted by Faculty of Psychology, SWPS University of Social Sciences and Humanities, Wroclaw, Poland, approval number 03/P/12/2019. The project results will be disseminated through structured strategy implemented in collaboration with the Ministry of Health.Trial registration detailsThis trial was registered with www.clinicaltrials.gov; registration number NCT04291482.

BACKGROUND Digital health promotion programs tailored to the individual are a potential cost-effective and scalable solution to enable self-management and provide support to people with excess body weight. However, solutions that are personalised, theory- and evidence- based and widely accessible are still limited. OBJECTIVE This study aimed to develop a digital behaviour change program, Choosing Health, that could identify modifiable predictors of weight loss and maintenance for each individual and utilise these to provide tailored support. METHODS We applied an Intervention Mapping protocol to design the program. This systematic approach to develop theory- and evidence-based health promotion programs consisted of 6 steps: development of (1) a logic model of the problem, (2) model of change, (3) intervention design and (4) production, (5) the implementation plan, and (6) evaluation plan. The decisions made during the Intervention Mapping process were guided by theory, existing evidence, and our own research (including four focus groups, N=40, expert consultations, N=12 and interviews, N=11). The stakeholders included researchers, public representatives (including individuals with overweight and obesity), and experts from the variety of relevant backgrounds (including nutrition, physical activity, and healthcare sector). RESULTS Following a structured process, we developed a tailored intervention that has potential to reduce excess body weight and support behaviour changes in people with overweight and obesity. The Choosing Health intervention consists of tailored personalised text messages and email support that correspond with theoretical domains potentially predictive of weight outcomes for each participant. Intervention content includes behaviour change techniques to support motivation maintenance, self-regulation, habit formation, environmental restructuring, social support and addressing physical and psychological resources. CONCLUSIONS Use of an Intervention Mapping protocol enabled the systematic development of the Choosing Health intervention and guided the implementation and evaluation of the program. Through the involvement of different stakeholders, including representatives of general public, we were able to map out program facilitators and barriers while increasing ecological validity of the program, to ensure that we build an intervention that is useful, user friendly, and informative. We also summarised lessons learnt for the Choosing Health intervention development and for other health promotion programs. CLINICALTRIAL This is an Intervention Mapping study which is currently evaluated through a Randomised Controlled Trial. This trial was registered with www.clinicaltrials.gov; registration number NCT04291482. INTERNATIONAL REGISTERED REPORT RR2-10.1136/bmjopen-2020-040183

No abstract