Overweight and obesity are now on the rise, especially in developing countries. This can lead to increased burden of health care and poor quality of life. The main reasons behind the rise in these health problems include increasing consumption of fast foods, convenient or ready-to-eat meals, soft drinks, junk foods and sweets among adolescents and deviations in the physical patterns of adolescents - from playing at the field to playing computer games, watching television and surfing the internet. In this high-technology era, most adolescents have a sedentary lifestyle that includes watching television, playing internet games or surfing. Therefore, the best health promotion and education can be designed by using the ‘screen’ as a medium.

On the surface, it would seem obvious that frequent internet use is associated with a sedentary lifestyle and, therefore, is a risk factor for overweight and obesity. While this is true, the authors noted that there are other poorly understood underlying mechanisms through which internet use may influence body weight. For example, they pointed to studies that indicated excessive internet use adversely influences nutritional behaviours such as skipping meals (especially breakfast) and high snack consumption. Moreover, other studies linked internet overuse with psychological disorders such as neuroticism, anxiety and depression, all of which can affect weight control. Further studies clarifying these mechanisms are needed.

All the studies examined in this review were cross-sectional studies, meaning that data was collected from participants at only one specific point in time. Cohort studies in which data is collected from participants periodically over time can provide more conclusive evidence of causality. To date, however, there have been no major cohort studies conducted to study the link between internet use and weight. Given these limitations, the authors concluded, “it seems that heavy internet use is associated with higher odds of overweight and obesity. However, further studies, especially with prospective designs, are warranted to further elucidate any associations.”