According to the lastest study from Japan, it can. As someone who has engaged in solely real world and entirely virtual programmes, I agree with the study's findings that the best weight losses can be had from a combination of face-to-face and virtual interactions.
At Slimming World, for example, I know I have a wealth of online information to refer to which reinforces or sheds more light on what's been discussed in a meeting. The recipes you can find online are so varied that it sometimes feels like you have an entire cookery library at your fingertips.
Studies, such as this one, highlight the real world need for face-to-face support during the struggle to lose weight. For me, this makes my weight loss more of a social event, than a duty or something on the 'to-do' list. It makes that commitment far more personal. You aren't just attending for you, you're attending for your leader, your weight loss comrades, etc.
It also makes your weight loss experience much richer with deep insights into dieting creativity. There are also 'tips' which may be useful or stories which 'touch a chord' with your own personal journey.