Unhealthy weight control behaviours in adolescent girls: a process model based on self-determination theory

Abstract

This study used self-determination theory (Deci, E.L., & Ryan, R.M. (2000). The ‘what’ and ‘why’ of goal pursuits: Human needs and the self-determination of behavior. Psychological Inquiry, 11, 227–268.) to examine predictors of body image concerns and unhealthy weight control behaviours in a sample of 350 Greek adolescent girls. A process model was tested which proposed that perceptions of parental autonomy support and two life goals (health and image) would predict adolescents’ degree of satisfaction of their basic psychological needs. In turn, psychological need satisfaction was hypothesised to negatively predict body image concerns (i.e. drive for thinness and body dissatisfaction) and, indirectly, unhealthy weight control behaviours. The predictions of the model were largely supported indicating that parental autonomy support and adaptive life goals can indirectly impact upon the extent to which female adolescents engage in unhealthy weight control behaviours via facilitating the latter's psychological need satisfaction.

Keywords:

• parental autonomy support
• life goals
• psychological need satisfaction
• body image concerns

Notes

Note

1. An anonymous reviewer requested that we removed the overweight and obese participants from the data set and repeat the SEM analysis to ensure that our results are not attributable to this group. We did so and the fit indices of the new model were very similar to the fit indices of the original model: Robust χ²(97) = 147.62, p < 0.01; robust NNFI = 0.96, robust CFI = 0.97, robust RMSEA = 0.04, SRMR = 0.06. Further, most path coefficients were very similar in size and direction with the exception, as one might expect, of the path coefficients from BMI to body image concerns (β = 0.69; β = 0.84 in the original model), and from body image concerns to unhealthy weight control behaviours (β = 0.31; β = 0.48 in the original model). We prefer not to exclude overweight and obese adolescents from our study and, therefore, we decided to present the original model in Figure 1.