According to World Health Organization (WHO), the prevalence of obesity among all nations has nearly doubled since 1980. High body mass index (BMI) is one of the major risk factors of many non-communicable diseases (NCD) and is the result of unhealthy diet and physical inactivity. In Hong Kong, the Department of Health (DH) found in 2012, through the telephone surveys, that nearly 40% of adults were overweight or obese. About 60% of total registered deaths in Hong Kong were due to four major preventable NCD, which were cancer, heart diseases, stroke and chronic lower respiratory diseases. Therefore, population-based interventions for collective health benefits, especially regarding weight management, are essential in lowering the risk of NCD in the total population.

Given the high proportion of overweight and obese individuals among the local population, achieving modest or even small behavioral changes in diet or activity could potentially lead to significant improvements in public health. Promotion of healthy diets and physical activity is one of the five recommended cost-effective interventions that have been addressed in The Lancet Series. The implementation of policies to promote healthy diets - reducing sugary beverages, in particular - and physical activity due to the likelihood of wide-ranging health gains, including prevention of overweight and cardiovascular disease, on a population level is advocated.

Facing the same challenges of the rest of the world that many residents are lacking of attention on healthy lifestyle, the Hong Kong SAR Government has a burden to improve the well-being of the general public. The Government has recently established a Committee on 'Reduction of Salt and Sugar in Food'. They will steer the direction, formulate and oversee the Action Plans for Salt and Sugar Reduction in Hong Kong. The aim is to reduce the intake of salt and sugar by residents to meet the WHO recommendations. The Centre for Food Safety showed that carbonated drinks and fruit juices were popular in Hong Kong. However, the added sugar does not have any nutritional value but increases the risk of overweight and obesity. Therefore, the promotion of healthy family diet is appropriate for improving a current public health situation in Hong Kong. On the other hand, the Leisure and Cultural Services Department have been jointed with the Department of Health to launch the 'Healthy Exercise for All Campaign' for raising the public's interest in exercising. However, none of the campaigns have addressed the problems and barriers of the sedentary people and their families. The barriers include myths and wrong perceptions, e.g.; exercise has to be difficult, or one has to find much time, spend much money and do lots of high intensive exercise to be beneficial.

This project is aimed to motivate participants to improve start with 'zero-time exercise' and reduce sugary beverages, which can be incorporated into daily life to reduce day-to-day sedentary time and sugar intake together with family members of all ages, that can then act as a trigger for active and healthy lifestyle. Few exercises can be done by the family members together. The investigators shall motivate participants to share what they have learned with their family members and to do 'zero-time exercise' and reduce sugary beverage's intake together. This project includes three major components: Train-the-trainer and -ambassador workshop, community-based family interventions, and public education events. Knowledge and skills of the community leaders and ambassadors will be strengthened through the 'Train-the-trainer and -ambassador' workshop. The trainees will be expected to help the implementation of community-based family interventions and public education events on the personal and family holistic health of the community participants.

Outcome and process evaluations will be used to assess the engagement, implementation and effectiveness of the project. Focus group and in-depth interviews will be conducted to obtain feedback, and opinion of the community leaders, ambassadors and community participants. Quantitative questionnaire assessments will be conducted at different time points to assess the effectiveness of the project on the key components of personal and family holistic health, and family well-being. The assessment time points are before and immediately after the core session, before and after the booster session at one month, three months, six months for community participants. An additional assessment for the community leaders and ambassadors is nine months.