Abstract

Prior research has demonstrated that dieting, or the restriction of caloric intake, is not effective in the long term. This dissertation hypothesizes that one reason dieting does not work is because it is a chronic stressor that increases perceived psychological stress and cortisol—both known factors involved in weight gain. Further, this study examined the respective roles of monitoring as well as restricting one's caloric intake in causing stress. In a 2 (monitoring vs. not monitoring) x 2 (restricting vs. not restricting) fully-crossed, randomized, controlled experiment, 121 female participants were randomly assigned to one of four conditions for a period of three weeks. In the monitoring conditions, participants completed daily food diaries to monitor caloric intake. In the restricting conditions, participants limited their caloric intake to 1200 kilocalories per day. Results indicated that monitoring increased perceived stress while restricting increased cortisol. In conclusion, dieting was found to cause stress, and thus stress may be one mechanism through which dieting fails.