Thank you for your comment Mary. Yes, that is correct, eating in groups sometimes results in increased food intake. Luckily, the study used another group of comparable size, to control for such confounds.

The size of the group is not the only factor affecting eating behavior. Other factors may include gender of the those in the group, and the individual's relationship to these people. For instance, an individual may feel more self-conscious when eating in a group of strangers. And this can result in reduced food intake.

Thank you for your comment.