Subjects in the long-term group that tested as having low SNI—in other words, low susceptibility to social pressure—achieved an average of 90% of their weight loss goals. In contrast, individuals who tested as having high SNI exceeded their weight loss goals by a significant margin: an average of nearly 105%.
What this study tells us is that in general the public commitment principle produces results, especially if the commitment is long-term. But, in the mix of people who make the commitment, those who genuinely fear social disapproval—not a personality trait usually given very high marks–will likely succeed the most. Those who couldn’t care less what others think are, ironically, more likely to come up short.