Table 2 Behavior strategies and corresponding platform features

Knowledge/empowerment

Short educational texts on healthy dietary, physical activity and sleeping habits

Short texts on behavioral strategies to enhance self-efficacy

Low-calorie menu suggestions

Recipes

Metabolic resting energy expenditure calculations based on age and activity level

Physical activity tips according to exercise preferences

Goal setting

Weight loss and calorie intake goal setting oriented by realistic goals

Graphical display of changes in weight, BMI and waist

Individualized daily calorie targets to facilitate 0.5–1 kg weight loss per week, based on participants weight, height and activity level

Outcomes expectations

Automated recommendations on realistic goals linked to self-monitoring features

Self-monitoring

Searchable online food diary to facilitate entry of food data

Automated weekly reminders for entering weight and specific habits considered ‘weak points’ by the user

Calculations summaries of energy balance and nutrition referenced to recommended nutrient targets and individualized goals

Modeling

Recipes

Promotion of users´ successful weight loss/behavior change reports on the online social network

Scenarios with clinical cases to educate users on how to deal with weight loss issues based on real situations

Social support

Online forums with participation of the users and of the project team for informational and emotional support, as well as problem-solving assistance

Challenges, which can be shared in the platform social network

Personalization

Definitions of individual ‘weak points’

Automated, computer-generated, personalized feedback based on their diet and physical activity diaries, ‘weak points’ and on the use of website features