Appetite (2002) 38, 39±44 doi:10.1006/appe.2001.0445, available online at http://www.idealibrary.com on 1 Original Article Rigid vs. flexible dieting: association with eating disorder symptoms in nonobese women Tiffany M. Stewart, Donald A.Williamson and Marney A.White Louisiana State University and Pennington Biomedical Research Center, Baton Rouge, LA, U.S.A. (Received 1August 2001, final revision 16 November 2001, accepted in revised form 20 December 2001) The correlates of rigid and flexible dieting were examined in a sample of 188 nonobese women recruited from the community and from a university. The primary aim of the study was to test the hypothesis that women who utilize rigid versus flexible dieting strategies to prevent weight gain report more eating disorder symptoms and higher body mass index (BMI) in comparison to women who utilize flexible dieting strategies. The study sample included women who were underweight (29%), normal weight (52%), and overweight (19%). None of the women were obese, as defined by BMI > 30. Participants were administered a questionnaire that measures Rigid Control and Flexible Control of eating. Body weight and height were measured and measures of eating disorder symptoms and mood disturbances were administered. Our results indicated that BMI was significantly correlated with rigid dieting and flexible dieting. BMI was controlled statistically in other analyses. The study found that individuals who engage in rigid dieting strategies reported symptoms of an eating disorder, mood disturbances, and excessive concern with body size/shape. In contrast, flexible dieting strategies were not highly associated with BMI, eating disorder symptoms, mood disturbances, or concerns with body size. Since this was a cross sectional study, causality of eating disorder symptoms could not be addressed. These findings replicate and extend the findings of earlier studies. These findings suggest that rigid dieting strategies, but not flexible dieting strategies, are associated with eating disorder symptoms and higher BMI in nonobese women. # 2002 Elsevier Science Ltd Introduction The term dietary restraint refers to a person's intent to restrict dietary intake to control body weight (Herman & Mack, 1975). Dietary restraint has been hypothesized to play an important role in determining binge eating associated with eating disorders (Polivy & Herman, 1985). The Three Factor Eating Questionnaire (TFEQ), developed by Stunkard and Messick (1985), measures dietary restraint, disinhibition (overeating), and per- ceived hunger. The dietary restraint scale of the TFEQ measures cognitive control of eating behaviour. In a subsequent study of the TFEQ, Westenhoefer (1991) found evidence that the construct of dietary restraint could be separated into two dieting strategies, that he called ``rigid control'' and ``flexible control'' of eating behaviour. Rigid control was characterized by dichotomous ``all or nothing'' approach to eating, weight, and dieting. Rigid control was associated with a higher body mass index, more frequent and more severe binge eating episodes, and higher scores of disinhibition (overeating). In contrast, flexible control was characterized by a more graduated approach to eating, weight, and dieting. Flexible control was associated with lower body mass index, less frequent and less severe binge eating or overeating, and a higher probability of successful weight loss during a one-year weight loss program. Subsequent research (McGuire et al., Shearin et al., 1994; Smith et al., 1998; Williamson et al., 1995) provided partial support for the initial findings of Westenhoefer (1991). A key difference in the findings of these studies was that some investiga- tions found that flexible control was associated with lower BMI and others did not. Westenhoefer, Stunkard and Pudel (1999) added items to the original scales and validated two revised Address correspondence to: Donald A. Williamson, Ph.D., Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, U.S.A. E-mail: Williada@pbrc.edu 0195±6663/02/010039+06 $35.00/0 # 2002 Elsevier Science Ltd