Purpose - Addressing overweight in the population is an important public health challenge. Use of social media such as Facebook has been proposed as a platform to deliver weight loss interventions to influence behavior change to tackle obesity. The purpose of this paper is to compare the effectiveness of weight loss education and support interventions delivered through online social media (experimental group) vs conventional method (control group).

Design/methodology/approach-The six-month experimental study comprised of a four-month intervention and a two-month follow up from May 2016 to October 2016. All faculties in a university were randomly selected into the experimental or control group. Then, undergraduate students (n=66) were randomly recruited from each faculty into the corresponding groups (experimental group=33 and control group=33). Both groups received health education and support services through either Facebook or the offline support system. The mean differences of main outcomes including body mass index (BMI) and waist to height ratio (WHtR) between groups at baseline and fourth month and baseline and sixth month were compared using t-test.

Findings-The results show those in the experimental group had significantly better outcomes in term of BMI and WHtR at the end of four-month intervention with the mean difference (95% CI) at 0.7 (0.1, 1.3) and 0.01 (0.00, 0.01), respectively. The differences at the end of the study, however, became insignificant.

Originality/value-The health education and support services through Facebook can be used in a weight loss promotion program for BMI and WHtR reduction. On a larger scale to replace conventional programs, a long-term continuous measure is needed.