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Biological, psychological, and sociocultural correlates of body change strategies and eating problems in adolescent boys and girls
Eating Behaviors 6 (2005) 11 – 22
Biological, psychological, and sociocultural correlates of body change strategies and eating problems in adolescent boys and girls Peter Muris a,*, Cor Meesters b, Willemien van de Blom b, Birgit Mayer a a
Institute of Psychology, Erasmus University Rotterdam, Burgemeester Oudlaan 50, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands b Department of Medical, Clinical, and Experimental Psychology, Maastricht University, The Netherlands Received 10 December 2003; received in revised form 12 February 2004; accepted 26 March 2004
Abstract The present study examines correlates of body change strategies and eating problems in youths. A large sample of adolescents aged 12 to 16 years (N = 307) was asked to complete a set of questionnaires, which measured biological (age, pubertal status, and body mass index [BMI]), psychological (self-esteem, body dissatisfaction, body importance, and body comparison), and sociocultural variables (influence of media, parents, and peers), as well as body change strategies and disturbed eating attitudes and behaviors. Results showed that boys generally try to become more muscular, whereas girls attempt to lose weight. Further, correlational and regression analyses demonstrated that biological, psychological, and sociocultural influences made unique and significant contributions to various body image and body change/eating problems variables. Finally, hierarchical regression analyses yielded theoretically meaningful models for the main body change strategies in boys and girls. In these models, BMI, self-esteem, and sociocultural influences turned out to be significant predictor variables, while bodyimage-related factors, and in particular body comparison (i.e., the tendency to compare one’s body with that of others), partially or fully mediated the influence of some predictor variables. D 2004 Elsevier Ltd. All rights reserved. Keywords: Body change strategies; Eating behavior and attitudes; Biological, psychological, and sociocultural influences; Adolescents
* Corresponding author. Tel.: +31-10-408-8706; fax: +31-10-408-9009. E-mail address: [email protected] (P. Muris). 1471-0153/$ - see front matter D 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.eatbeh.2004.03.002
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1. Introduction In the current Western society, being thin is highly valued among women, whereas being slim and muscular is strongly appreciated among men. There is evidence indicating that these cultural values related to ideal body images are already present in children and adolescents (see for a review Ricciardelli & McCabe, 2001a). Not surprisingly, research has shown that a considerable proportion of the youths report subjective feelings of dissatisfaction with their physical appearance. More specifically, girls typically describe themselves as being overweight and thus frequently have thoughts about being thinner (e.g., Thomas, Ricciardelli, & Williams, 2000). Boys display a less consistent pattern of body image dissatisfaction. One half of them also wants to be thinner, whereas the other half has the wish to become more muscular (e.g., Ricciardelli, McCabe, & Banfield, 2000). It is clear that such body change strategies can take the form of an eating disorder (Steiner & Lock, 1998) or other health-risk behaviors such as the use of anabolic steroids (e.g., Irving, Wall, Neumark-Sztainer, & Story, 2002). Various biological, psychological, and sociocultural factors seem to be associated with children’s body change strategies and eating problems. As to the biological factors, body mass index (BMI) seems to be an important predictor of body dissatisfaction and, in its wake, body change strategies. In studies of children (Holt & Ricciardelli, 2002) and adolescents (Neumark-Sztainer, Story, Flakner, Beuhring, & Resnick, 1999), BMI was found to be an important predictor of body dissatisfaction in both boys and girls. Age seems to be another biological factor that might be involved in body image and body change strategies. For example, there is some evidence suggesting that with increasing age, children are more concerned about becoming overweight (e.g., Lawrence & Thelen, 1995). A further biological correlate of body change strategies and eating problems seems to be pubertal development. It is obvious that with the onset of puberty, several physical changes take place (Tanner, 1998). Clearly, such changes may prompt adolescents to focus on their body, whereas the quality and quantity of the physical changes may give rise to body dissatisfaction and, in its wake, increased dieting and disordered eating (Attie & Brooks-Gunn, 1989; Gralen, Levine, Smolak, & Murnen, 1990). Besides biological factors, there seem to be a number of psychological factors that are associated with children’s body change strategies and eating problems. A first factor that should be mentioned in this context is self-esteem. Studies by Ricciardelli and McCabe (2001c, 2003) have demonstrated that poor self-esteem in male and female youth was associated with higher levels of body dissatisfaction. Other psychological factors that are mentioned in the literature have to do with the way in which children and adolescents perceive and evaluate the shape of their body. Besides the aforementioned factor of body dissatisfaction (McCabe & Ricciardelli, 2003b; Ricciardelli & McCabe, 2001b, 2001c), there seem to be two other relevant body-image-related factors, namely, body importance and body comparison. The idea is that when children evaluate body shape as important and have the tendency to compare their body with that of others, they are more likely to engage in body change strategies (Holt & Ricciardelli, 2002; Ricciardelli & McCabe, 2001a, 2003). Sociocultural factors constitute the third group of variables that are associated with body change strategies and eating problems. The results of a wide range of studies suggest that sociocultural ideas about body shape of men and women are transmitted through the media. More precisely, popular magazines and movies almost exclusively depict role models of females with slender and males with
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muscular bodies (e.g., Pope, Phililips, & Olivardia, 2000). These sociocultural pressures regarding body ideals of men and women also seem to determine children and adolescents’ body image concerns and related body change behaviors (Cusamano & Thompson, 2000; McCabe & Ricciardelli, 2003c; McCabe, Ricciardelli, & Finemore, 2002; Ricciardelli & McCabe, 2001c, 2003; Ricciardelli et al., 2000). In addition to media influences, various studies have shown that parents and peers may also have a significant impact on children and adolescents’ perception of their own body and, in its wake, body change strategies (McCabe & Ricciardelli, 2003c; Ricciardelli & McCabe, 2003). While previous research has identified various biological, psychological, and sociocultural factors that may contribute to body change strategies and eating problems in children and adolescents (Ricciardelli & McCabe, 2001a), it is clear that most studies have only focused on a limited number of factors. However, there are a few studies that have included several factors in an attempt to look at their relative contribution to body change strategies in youths. Ricciardelli and McCabe (2001c) showed that both psychological factors (self-esteem and negative affect) and sociocultural pressures made unique and significant contributions to adolescents’ levels of body dissatisfaction and body change strategies. In a further study, Ricciardelli and McCabe (2003) also reported unique contributions of psychological (i.e., self-esteem, negative affect, body dissatisfaction, and body importance) and sociocultural (i.e., influence of the media, and parent and peer encouragement) factors to body change strategies. In addition, the data seemed to indicate that body dissatisfaction and body importance partly mediated the relationship between self-esteem, negative affect, and sociocultural factors on one hand, and body change strategies on the other. A final study by McCabe and Ricciardelli (2003c) not only examined the role of psychological and sociocultural factors but also included biological parameters, namely, age, pubertal status, and BMI. Results indicated that negative affect, BMI, and a broad range of sociocultural influences (i.e., influence of the media and social pressure of parents and peers) were independent predictors of body change strategies. To the present authors’ knowledge, the McCabe and Ricciardelli (2003c) study is the only one, which examined relationships between a broad range of factors (i.e., biological, psychological, and sociocultural) and body change strategies in youths. Clearly, more studies of this type are necessary to formulate adequate multifactorial models for the development of body change strategies and eating disorders in children and adolescents. With this in mind, the present study was undertaken. A large sample of adolescents were asked to complete a set of questionnaires, which measured a variety of biological, psychological, and sociocultural risk factors, as well as body change strategies and disturbed eating attitudes and behaviors. Hierarchical regression analyses was employed to evaluate the relative contributions of various factors and to find plausible models for the development of body change strategies and disturbed eating in youths.
2. Method 2.1. Participants Participants were 307 adolescents (155 boys and 152 girls) who were recruited from a regular secondary school in Maastricht, The Netherlands. Mean age of the children was 13.6 years (S.D. = 1.0,
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range = 12–16 years). Children were recruited in various educational levels. Percentages of children with a low, middle, or high socioeconomic background were 26.1%, 57.3%, and 16.6%, respectively. The vast majority of the children were Caucasian (i.e., 89.9%). 2.2. Questionnaires Body change strategies were assessed by means of the Body Change Inventory (BCI; Ricciardelli & McCabe, 2002). Two subscales of this measure were used, namely, ‘‘decrease body size’’ and ‘‘increase muscle size.’’ Eating problems were measured with a modified version of the Children’s Eating Attitude Test (ChEAT; Maloney, McGuire, & Daniels, 1988), a 32-item questionnaire for assessing problem attitudes and behaviors with regard to eating, exercise, and muscles. Based on a factor analysis of the present ChEAT data, four domains of eating problems were identified, namely, ‘‘dieting,’’ ‘‘muscle development,’’ ‘‘social pressure to eat,’’ and ‘‘food preoccupation’’ (see Kelly, Ricciardelli, & Clarke, 1999). Body satisfaction and body importance were assessed with subscales of the Body Image Inventory (see McCabe et al., 2002). The body satisfaction scale asks children and adolescents to indicate how satisfied they are with various parts of their body (i.e., hips, thighs, breast(s), stomach, shoulders, arms, and legs). The body importance scale asks youths to indicate how important it is what these body parts look like. Body comparison was measured with the Body Comparison Scale (Holt & Ricciardelli, 2002), which assesses the frequency with which children and adolescents compare their own body with that of other youths of the same sex. General levels of self-esteem were assessed by means of the global self-worth subscale of the Self-Perception Profile for Children (SPPC; Harter, 1985). The sociocultural influences scales of the Body Image and Body Change Questionnaire (McCabe & Ricciardelli, 2001) were used to measure perceived encouragement to lose weight and increase muscles from parents, peers, and media. Pubertal status was measured with the Pubertal Development Scale (Petersen, Crockett, Richards, & Boxer, 1988). Boys were asked to rate the development of their body hair, voice change, skin change, growth spurt, and growth of beard, whereas girls were asked to score the development of their body hair, growth of breasts, skin change, growth spurt, and menarche. All respondents not only provided information on age but also on weight and height so that it became possible to compute their BMI. 2.3. Data analysis and model testing As it was assumed that there were clear gender differences with respect to body change strategies and eating problems, analyses were carried out for boys and girls separately. Correlations were computed between biological, psychological, and sociocultural risk factors on one hand, and body change strategies and disturbed eating attitudes and behaviors on the other. Further, regression analyses were carried out to test the relative contributions of various factors to body image variables, body change strategies, and eating problems. Finally, hierarchical regression analysis was performed to test a model in which biological, trait-like psychological (i.e., self-esteem), and sociocultural factors were the predictor variables, body-image-related factors were the intermediate variables, and body change strategies and eating problems were the dependent variables.
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3. Results 3.1. General findings Before addressing the main research issues, a number of general findings should be discussed. To begin with, questionnaires were generally reliable in terms of internal consistency (with most Cronbach’s alphas>.60). Further, as anticipated, girls displayed higher scores on scales referring to dieting and losing weight, whereas boys had higher scores on scales referring to becoming more muscular. 3.2. Correlates of body change strategies and eating problems Correlations between biological, psychological, and sociocultural factors on one hand, and body change strategies and eating problems on the other generally showed the predicted pattern. For example, in both genders, higher BMI was associated with stronger attempts to lose weight (rs between .46 and .52, Ps < .001). Further, high levels of body importance and body comparison were accompanied by stronger attempts to become more muscular (boys and girls; rs between .28 and .52, Ps < .001) and strategies to lose weight (girls; rs between .27 and .66, Ps < .001). In girls, lower levels of body satisfaction and self-esteem were associated with stronger attempts to lose weight and greater preoccupation with food (rs between .26 and .39, Ps < .001). Sociocultural factors were also significantly linked to body change strategies and eating problems (rs between .24 and .69, Ps < .005); that is, higher levels of encouragement by parents, peers, and media to lose weight or to increase muscles were accompanied by higher levels of corresponding body change strategies and eating problems. In boys, age and pubertal development were to some extent positively related to attempts to increase muscles (rs being .23 and .24, Ps < .005). 3.3. Relative contributions of various factors to body image, body change strategies, and eating problems 3.3.1. Boys Table 1 presents the results of stepwise regression analyses examining the relative contributions of various factors to body image, body change strategies, and eating problems in boys. Body image variables were predicted by various psychological and sociocultural factors, which accounted for between 23% and 27% of the total variance. More specifically, higher levels of self-esteem but lower levels of parent, peer, and media pressure to lose weight were accompanied by lower levels of body satisfaction. Note also that body importance made a unique contribution to body satisfaction and vice versa. The positive partial correlations indicate that higher levels of body importance were associated with higher levels of body satisfaction. As can be seen in Table 1, body comparison in boys was mainly predicted by parent, peer, and media pressure to become more muscular. As to the predictors of body change strategies and eating problems in boys, five remarks are in order. First, predictor variables together accounted for between 13% and 54% of the variance in boys’ body change and eating problems scores. Second, BMI uniquely contributed to BCI decrease body size and ChEAT dieting scores. As expected, higher BMI levels were associated with stronger attempts to lose weight. Third, in most regression equations, influences of parent, peer, and media made a significant contribution to most body change and eating problem scores. Fourth, of the body-image-related factors,
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Table 1 Results of the stepwise regression analysis predicting body image, body change strategies, and eating problems of boys Dependent
Predictors
Body satisfaction [ F(3,151) = 18.8, P < .001, R2=.27]
(1) (2) (3) (1) (2) (1) (2) (1) (2) (3) (1) (2) (1) (2) (3) (1) (2) (3) (4) (1) (2) (3) (1) (2) (1)
Body importance [ F(2,152) = 22.9, P < .001, R2=.23] Body comparison [ F(2,152) = 25.4, P < .001, R2=.25] BCI decrease body size [ F(3,151) = 43.6, P < .001, R2=.46] BCI increase muscle size [ F(2,152) = 29.7, P < .001, R2=.28] ChEAT total score [ F(3,151) = 47.5, P < .001, R2=.49] ChEAT dieting [ F(4,150) = 44.8, P < .001, R2=.54]
ChEAT muscle development [ F(3,151) = 37.3, P < .001, R2=.43] ChEAT social pressure to eat [ F(2,152) = 11.2, P < .001, R2=.13] ChEAT food preoccupation [ F(1,153) = 26.0, P < .001, R2=.15]
Self-esteem Body importance Parent and peer—Decrease weight Body satisfaction Body comparison Media—Increase muscle size Parent and peer—Increase muscle size Parent and peer—Decrease weight Media—Decrease weight BMI Parent and peer—Increase muscle size Body importance Body comparison Parent and peer—Increase muscle size BMI Parent and peer—Decrease weight Media—Decrease weight Body comparison BMI Parent and peer—Increase muscle size Body comparison Body importance Pubertal status Body comparison Body comparison
Partial r
t
.32 .33 .24 .42 .33 .30 .27 .58 .34 .30 .46 .29 .58 .42 .24 .65 .34 .23 .23 .53 .35 .30 .26 .25 .38
4.1 4.3 3.0 5.7 4.3 3.8 3.5 8.8 4.4 3.9 6.4 3.8 8.8 5.7 3.0 10.6 4.5 3.0 3.0 7.7 4.6 3.8 3.4 3.2 5.1
P < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .001 < .001 < .001 < .001 < .005 < .001 < .001 < .005 < .005 < .001 < .001 < .001 < .001 < .005 < .001
n = 155. The probability of the F to enter in the equation was set on P < .05/11.
body comparison (all ChEAT scores) and body importance (BCI increase muscle size and ChEAT muscle development) appeared to be unique predictors. Finally, pubertal status accounted for unique variance in ChEAT social pressure to eat scores. The partial correlation was negative and thus indicated that boys with a more proceeded pubertal development experienced less social pressure to eat. 3.3.2. Girls Table 2 displays the results of the stepwise regression analysis predicting body change strategies and eating problems in girls. As can be seen, body image variables were uniquely predicted by various factors, including self-esteem, BMI, and sociocultural influences. In total, predictor variables declared 20% to 56% of the variance in girls’ body image scores. In the regression equations predicting body change strategies and eating problems of girls, unique contributions were predominantly made by body comparison and influences of parent, peer, and media. Most relationships were as expected, and in total, significant predictors accounted for between 15% and 63% of the variance in BCI and ChEAT scores. However, two results require some further comment. First, perceived pressure of the media to increase muscle size made a significantly negative contribution to BCI decrease body size and ChEAT dieting. Apparently, higher
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Table 2 Results of the stepwise regression analysis predicting body image, body change strategies, and eating problems of girls Dependent
Predictors
Body satisfaction [ F(2,149) = 37.4, P < .001, R2=.33] Body importance [ F(1,150) = 36.4, P < .001, R2=.20] Body comparison [ F(3,148) = 63.8, P < .001, R2=.56] BCI decrease body size [ F(5,146) = 60.6, P < .001, R2=.68]
BCI increase muscle size [ F(2,149) = 32.0, P < .001, R2=.30] ChEAT total score [ F(3,148) = 71.1, P < .001, R2=.59] ChEAT dieting [ F(4,147) = 63.2, P < .001, R2=.63]
ChEAT muscle development [ F(2,149) = 44.1, P < .001, R2=.37] ChEAT social pressure to eat [ F(2,149) = 12.9, P < .001, R2=.15] ChEAT food preoccupation [ F(1,150) = 48.0, P < .001, R2=.24]
Partial r
t
(1) Self-esteem (2) BMI (1) Body comparison
.47 .32 .44
6.6 4.1 6.0
< .001 < .001 < .001
(1) (2) (3) (1) (2) (3) (4) (5) (1) (2) (1) (2) (3) (1) (2) (3) (4) (1) (2) (1) (2) (1)
.59 .38 .29 .68 .47 .31 .30 .25 .45 .35 .69 .40 .24 .69 .43 .32 .24 .52 .37 .37 .24 .49
8.8 5.0 3.7 11.3 6.5 3.9 3.9 3.1 6.2 4.5 11.8 5.3 3.1 10.6 5.8 4.0 2.9 7.4 4.9 4.9 3.0 6.9
< .001 < .001 < .001 < .001 < .001 < .001 < .005 < .005 < .001 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001
Media—Decrease weight Body importance Self-esteem Media—Decrease weight Parent and peer—Decrease weight Body comparison Media—Increase muscle size BMI Body comparison Parent and peer—Increase muscle size Body comparison Parent and peer—Decrease weight Media—Decrease weight Media—Decrease weight Parent and peer—Decrease weight Media—Increase muscle size Body comparison Body comparison Parent and peer—Increase muscle size Body comparison BMI Body comparison
P
n = 152. The probability of the F to enter in the equation was set on P < .05/11.
levels of perceived media pressure to increase muscle size were accompanied by lower levels of attempts to decrease body weight. Second, BMI accounted for unique variance in BCI decrease body size and ChEAT social pressure to eat scores. Partial correlations were respectively positive
Fig. 1. Regression model for ChEAT muscle development scores of boys.
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Fig. 2. Regression model for ChEAT muscle development scores of girls.
and negative, indicating that higher BMI was accompanied by greater attempts to lose weight and less social pressure to eat. 3.4. Models of body change strategies in boys and girls Figs. 1–4 summarize the final regression models of the main body change strategies in boys and girls (i.e., losing weight and becoming more muscular). When predicting muscle development of boys, a model emerged in which sociocultural pressures to increase muscle size, body comparison, and body importance had either direct or indirect influences. Similar predictors were found in the model explaining girls’ attempts to become more muscular. Note, however, that in girls, sociocultural pressures to decrease weight were the main determinants of body comparison, which in turn had a positive effect on strategies to develop muscles.
Fig. 3. Regression model for ChEAT dieting scores of boys.
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Fig. 4. Regression model for BCI decrease body size scores of girls.
The models explaining strategies to lose weight were generally comparable for boys and girls. More specifically, in both genders, BMI, sociocultural pressure to decrease weight, and body comparison were the key elements. A number of differences were also observed. First, self-esteem played a role in the model of decreasing body size in girls. As can be seen in Fig. 4, low levels of self-esteem contributed to girls’ tendency to compare their body with others, which in turn was an important determinant of BCI decrease body size. Second, in boys, sociocultural influences to increase muscle size were a significant predictor of body comparison, whereas in girls, sociocultural pressures to decrease weight significantly determined this body-image-related psychological factor. Finally, in girls, media pressures to increase muscle size had a direct negative effect on BCI decrease body size.
4. Discussion The current study examined relationships between biological (age, pubertal status, and BMI), psychological (self-esteem, body dissatisfaction, body importance, and body comparison), and sociocultural risk factors (influence of media, parents, and peers) on one hand, and body change strategies and disturbed eating attitudes and behaviors on the other in a sample of nonclinical adolescent boys and girls. The main findings can be catalogued as follows. First of all, as expected, boys displayed higher levels of attempts to become more muscular, whereas girls showed a stronger tendency for strategies to lose weight. Second, results demonstrated that biological, psychological, and sociocultural influences made unique and significant contributions to various body image and body change/eating problem variables. Third and finally, hierarchical regression analyses yielded theoretically meaningful models for the main body change strategies in boys and girls.
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In keeping with previous studies, BMI was found to be a consistent predictor of boys’ and girls’ attempts to lose weight (e.g., Holt & Ricciardelli, 2002; Neumark-Sztainer et al., 1999). The influence of the other biological factors, age and pubertal status, appeared marginal. Although age and pubertal development were to a certain extent positively related to attempts to become more muscular in boys, these variables did not explain unique variance in this type of body change strategy. Meanwhile, it may well be the case that the timing (i.e., age of onset) of the pubertal development is crucial for the development of body change strategies and eating problems (e.g., Ackard & Peterson, 2001; StriegelMoore et al., 2001). It is well conceivable that a too early or too late onset results in a deviation from the normal, age-appropriate body shape, which may have a negative impact on youths’ body image and, in its wake, may enhance body change strategies and eating problems. Only in girls did self-esteem appear to be a consistent correlate of strategies to lose weight (i.e., BCI decrease body size and ChEAT dieting). Moreover, the results of the hierarchical regression analyses suggest that self-esteem only has an indirect influence on girls’ body change strategies; that is, evidence emerged for a model in which self-esteem negatively contributed to body comparison, which in turn enhanced strategies to lose weight. Body-image-related psychological factors were in a theoretically meaningful way connected to body change strategies; that is, higher levels of body change strategies were associated with lower levels of body satisfaction (girls) and higher levels of body importance and body comparison (boys and girls). Further, it should be noted that in boys, body-image-related variables were most clearly connected to strategies to develop muscles; whereas in girls, these variables were most convincingly related to strategies to decrease weight. Surprisingly, while the results of the regression analyses indicated that body comparison appeared to be the most important body-image-related variable, none of the models included body satisfaction—a finding which is not in keeping with previous research (Ricciardelli & McCabe, 2001a, 2003). Note, however, that the current investigation was the first to include body satisfaction, body importance, and body comparison, hence having made it possible to study the relative contributions of these body-image-related factors. In line with previous studies, sociocultural influences were also found to be significantly related to body change strategies and eating problems (Cusamano & Thompson, 2000; McCabe & Ricciardelli, 2003c; McCabe et al., 2002; Ricciardelli & McCabe, 2000, 2001c, 2003). In general, these relations were as hypothesized, although we also obtained some unexpected findings. For example, the regression model predicting strategies to lose weight in girls, included a direct path from media—increase muscle size to BCI decrease body size. The negative (partial) correlation coefficient indicated that high levels of perceived media pressure to increase muscle size were accompanied by lower attempts to lose weight. Because correlational analysis revealed a positive relationship between media—increase muscle size and BCI decrease body size (r=.34, P < .001), it seems most likely that this link reflects a statistical artifact, which occurred as a result from partialling out the influence of highly related, concurrent predictor variables. It should be acknowledged that the current study suffers from various limitations. More precisely, the present study was correlational in nature, only relied on adolescents’ self-report, included no diagnostic interview instrument for assessing ‘clinical’ eating problems, and neglected a number of other potential risk factors for body change strategies and eating problems in youths (e.g., Lieberman, Gauvin, Bukowski, & White, 2001; McCabe et al., 2002; Ricciardelli & McCabe, 2001c). Despite these shortcomings, the data support previous findings in this research area and seem to suggest that body change strategies and eating problems in adolescents are determined by various biological, psychological, and psychosocial risk factors (e.g., Ricciardelli & McCabe, 2001a). Clearly, longitudinal research
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(e.g., McCabe & Ricciardelli, 2003a) is necessary to further evaluate the relative contributions of these variables in the development of eating disorders in youths.
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Ricciardelli, L. A., & McCabe, M. P. (2001b). Dietary restraint and negative affect as mediators of body dissatisfaction and bulimic behavior in adolescent girls and boys. Behaviour Research and Therapy, 39, 1317 – 1328. Ricciardelli, L. A., & McCabe, M. P. (2001c). Self-esteem and negative affect as moderators of sociocultural influences on body dissatisfaction, strategies to decrease weight, and strategies to increase muscles among adolescent boys and girls. Sex Roles, 44, 189 – 207. Ricciardelli, L. A., & McCabe, M. P. (2002). Psychometric evaluation of the Body Change Inventory: An assessment instrument for adolescent boys and girls. Eating Behaviors, 3, 45 – 59. Ricciardelli, L. A., & McCabe, M. P. (2003). Sociocultural and individual influences on muscle gain and weight loss strategies among adolescent boys and girls. Psychology in the Schools, 40, 209 – 224. Ricciardelli, L. A., McCabe, M. P., & Banfield, S. (2000). Body image and body change methods in adolescent boys: Role of parents, friends, and the media. Journal of Psychosomatic Research, 48, 189 – 197. Steiner, H., & Lock, J. (1998). Anorexia nervosa and bulimia nervosa in children and adolescents: A review of the past 10 years. Journal of the American Academy of Child and Adolescent Psychiatry, 37, 352 – 359. Striegel-Moore, R., McMahon, R. P., Biro, F. M., Schreiber, G., Crawford, P. B., & Voorhees, C. (2001). Exploring the relationship between timing of menarche and eating disorder symptoms in black and white adolescent girls. International Journal of Eating Disorders, 30, 421 – 433. Tanner, J. M. (1998). Sequence, tempo, and individual variation in growth and development of boys and girls aged twelve to sixteen. In R. E. Muuss, & H. D. Porton (Eds.), Adolescent behavior and society: A book of readings (5th ed.) (pp. 34 – 46). New York: McGraw-Hill. Thomas, K., Ricciardelli, L. A., & Williams, R. J. (2000). Gender traits and self-concept as indicators of problem eating and body dissatisfaction among children. Sex Roles, 43, 441 – 458.
Biological, psychological, and sociocultural correlates of body change strategies and eating problems in adolescent boys and girls Peter Muris a,*, Cor Meesters b, Willemien van de Blom b, Birgit Mayer a a
Institute of Psychology, Erasmus University Rotterdam, Burgemeester Oudlaan 50, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands b Department of Medical, Clinical, and Experimental Psychology, Maastricht University, The Netherlands Received 10 December 2003; received in revised form 12 February 2004; accepted 26 March 2004
Abstract The present study examines correlates of body change strategies and eating problems in youths. A large sample of adolescents aged 12 to 16 years (N = 307) was asked to complete a set of questionnaires, which measured biological (age, pubertal status, and body mass index [BMI]), psychological (self-esteem, body dissatisfaction, body importance, and body comparison), and sociocultural variables (influence of media, parents, and peers), as well as body change strategies and disturbed eating attitudes and behaviors. Results showed that boys generally try to become more muscular, whereas girls attempt to lose weight. Further, correlational and regression analyses demonstrated that biological, psychological, and sociocultural influences made unique and significant contributions to various body image and body change/eating problems variables. Finally, hierarchical regression analyses yielded theoretically meaningful models for the main body change strategies in boys and girls. In these models, BMI, self-esteem, and sociocultural influences turned out to be significant predictor variables, while bodyimage-related factors, and in particular body comparison (i.e., the tendency to compare one’s body with that of others), partially or fully mediated the influence of some predictor variables. D 2004 Elsevier Ltd. All rights reserved. Keywords: Body change strategies; Eating behavior and attitudes; Biological, psychological, and sociocultural influences; Adolescents
* Corresponding author. Tel.: +31-10-408-8706; fax: +31-10-408-9009. E-mail address: [email protected] (P. Muris). 1471-0153/$ - see front matter D 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.eatbeh.2004.03.002
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1. Introduction In the current Western society, being thin is highly valued among women, whereas being slim and muscular is strongly appreciated among men. There is evidence indicating that these cultural values related to ideal body images are already present in children and adolescents (see for a review Ricciardelli & McCabe, 2001a). Not surprisingly, research has shown that a considerable proportion of the youths report subjective feelings of dissatisfaction with their physical appearance. More specifically, girls typically describe themselves as being overweight and thus frequently have thoughts about being thinner (e.g., Thomas, Ricciardelli, & Williams, 2000). Boys display a less consistent pattern of body image dissatisfaction. One half of them also wants to be thinner, whereas the other half has the wish to become more muscular (e.g., Ricciardelli, McCabe, & Banfield, 2000). It is clear that such body change strategies can take the form of an eating disorder (Steiner & Lock, 1998) or other health-risk behaviors such as the use of anabolic steroids (e.g., Irving, Wall, Neumark-Sztainer, & Story, 2002). Various biological, psychological, and sociocultural factors seem to be associated with children’s body change strategies and eating problems. As to the biological factors, body mass index (BMI) seems to be an important predictor of body dissatisfaction and, in its wake, body change strategies. In studies of children (Holt & Ricciardelli, 2002) and adolescents (Neumark-Sztainer, Story, Flakner, Beuhring, & Resnick, 1999), BMI was found to be an important predictor of body dissatisfaction in both boys and girls. Age seems to be another biological factor that might be involved in body image and body change strategies. For example, there is some evidence suggesting that with increasing age, children are more concerned about becoming overweight (e.g., Lawrence & Thelen, 1995). A further biological correlate of body change strategies and eating problems seems to be pubertal development. It is obvious that with the onset of puberty, several physical changes take place (Tanner, 1998). Clearly, such changes may prompt adolescents to focus on their body, whereas the quality and quantity of the physical changes may give rise to body dissatisfaction and, in its wake, increased dieting and disordered eating (Attie & Brooks-Gunn, 1989; Gralen, Levine, Smolak, & Murnen, 1990). Besides biological factors, there seem to be a number of psychological factors that are associated with children’s body change strategies and eating problems. A first factor that should be mentioned in this context is self-esteem. Studies by Ricciardelli and McCabe (2001c, 2003) have demonstrated that poor self-esteem in male and female youth was associated with higher levels of body dissatisfaction. Other psychological factors that are mentioned in the literature have to do with the way in which children and adolescents perceive and evaluate the shape of their body. Besides the aforementioned factor of body dissatisfaction (McCabe & Ricciardelli, 2003b; Ricciardelli & McCabe, 2001b, 2001c), there seem to be two other relevant body-image-related factors, namely, body importance and body comparison. The idea is that when children evaluate body shape as important and have the tendency to compare their body with that of others, they are more likely to engage in body change strategies (Holt & Ricciardelli, 2002; Ricciardelli & McCabe, 2001a, 2003). Sociocultural factors constitute the third group of variables that are associated with body change strategies and eating problems. The results of a wide range of studies suggest that sociocultural ideas about body shape of men and women are transmitted through the media. More precisely, popular magazines and movies almost exclusively depict role models of females with slender and males with
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muscular bodies (e.g., Pope, Phililips, & Olivardia, 2000). These sociocultural pressures regarding body ideals of men and women also seem to determine children and adolescents’ body image concerns and related body change behaviors (Cusamano & Thompson, 2000; McCabe & Ricciardelli, 2003c; McCabe, Ricciardelli, & Finemore, 2002; Ricciardelli & McCabe, 2001c, 2003; Ricciardelli et al., 2000). In addition to media influences, various studies have shown that parents and peers may also have a significant impact on children and adolescents’ perception of their own body and, in its wake, body change strategies (McCabe & Ricciardelli, 2003c; Ricciardelli & McCabe, 2003). While previous research has identified various biological, psychological, and sociocultural factors that may contribute to body change strategies and eating problems in children and adolescents (Ricciardelli & McCabe, 2001a), it is clear that most studies have only focused on a limited number of factors. However, there are a few studies that have included several factors in an attempt to look at their relative contribution to body change strategies in youths. Ricciardelli and McCabe (2001c) showed that both psychological factors (self-esteem and negative affect) and sociocultural pressures made unique and significant contributions to adolescents’ levels of body dissatisfaction and body change strategies. In a further study, Ricciardelli and McCabe (2003) also reported unique contributions of psychological (i.e., self-esteem, negative affect, body dissatisfaction, and body importance) and sociocultural (i.e., influence of the media, and parent and peer encouragement) factors to body change strategies. In addition, the data seemed to indicate that body dissatisfaction and body importance partly mediated the relationship between self-esteem, negative affect, and sociocultural factors on one hand, and body change strategies on the other. A final study by McCabe and Ricciardelli (2003c) not only examined the role of psychological and sociocultural factors but also included biological parameters, namely, age, pubertal status, and BMI. Results indicated that negative affect, BMI, and a broad range of sociocultural influences (i.e., influence of the media and social pressure of parents and peers) were independent predictors of body change strategies. To the present authors’ knowledge, the McCabe and Ricciardelli (2003c) study is the only one, which examined relationships between a broad range of factors (i.e., biological, psychological, and sociocultural) and body change strategies in youths. Clearly, more studies of this type are necessary to formulate adequate multifactorial models for the development of body change strategies and eating disorders in children and adolescents. With this in mind, the present study was undertaken. A large sample of adolescents were asked to complete a set of questionnaires, which measured a variety of biological, psychological, and sociocultural risk factors, as well as body change strategies and disturbed eating attitudes and behaviors. Hierarchical regression analyses was employed to evaluate the relative contributions of various factors and to find plausible models for the development of body change strategies and disturbed eating in youths.
2. Method 2.1. Participants Participants were 307 adolescents (155 boys and 152 girls) who were recruited from a regular secondary school in Maastricht, The Netherlands. Mean age of the children was 13.6 years (S.D. = 1.0,
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range = 12–16 years). Children were recruited in various educational levels. Percentages of children with a low, middle, or high socioeconomic background were 26.1%, 57.3%, and 16.6%, respectively. The vast majority of the children were Caucasian (i.e., 89.9%). 2.2. Questionnaires Body change strategies were assessed by means of the Body Change Inventory (BCI; Ricciardelli & McCabe, 2002). Two subscales of this measure were used, namely, ‘‘decrease body size’’ and ‘‘increase muscle size.’’ Eating problems were measured with a modified version of the Children’s Eating Attitude Test (ChEAT; Maloney, McGuire, & Daniels, 1988), a 32-item questionnaire for assessing problem attitudes and behaviors with regard to eating, exercise, and muscles. Based on a factor analysis of the present ChEAT data, four domains of eating problems were identified, namely, ‘‘dieting,’’ ‘‘muscle development,’’ ‘‘social pressure to eat,’’ and ‘‘food preoccupation’’ (see Kelly, Ricciardelli, & Clarke, 1999). Body satisfaction and body importance were assessed with subscales of the Body Image Inventory (see McCabe et al., 2002). The body satisfaction scale asks children and adolescents to indicate how satisfied they are with various parts of their body (i.e., hips, thighs, breast(s), stomach, shoulders, arms, and legs). The body importance scale asks youths to indicate how important it is what these body parts look like. Body comparison was measured with the Body Comparison Scale (Holt & Ricciardelli, 2002), which assesses the frequency with which children and adolescents compare their own body with that of other youths of the same sex. General levels of self-esteem were assessed by means of the global self-worth subscale of the Self-Perception Profile for Children (SPPC; Harter, 1985). The sociocultural influences scales of the Body Image and Body Change Questionnaire (McCabe & Ricciardelli, 2001) were used to measure perceived encouragement to lose weight and increase muscles from parents, peers, and media. Pubertal status was measured with the Pubertal Development Scale (Petersen, Crockett, Richards, & Boxer, 1988). Boys were asked to rate the development of their body hair, voice change, skin change, growth spurt, and growth of beard, whereas girls were asked to score the development of their body hair, growth of breasts, skin change, growth spurt, and menarche. All respondents not only provided information on age but also on weight and height so that it became possible to compute their BMI. 2.3. Data analysis and model testing As it was assumed that there were clear gender differences with respect to body change strategies and eating problems, analyses were carried out for boys and girls separately. Correlations were computed between biological, psychological, and sociocultural risk factors on one hand, and body change strategies and disturbed eating attitudes and behaviors on the other. Further, regression analyses were carried out to test the relative contributions of various factors to body image variables, body change strategies, and eating problems. Finally, hierarchical regression analysis was performed to test a model in which biological, trait-like psychological (i.e., self-esteem), and sociocultural factors were the predictor variables, body-image-related factors were the intermediate variables, and body change strategies and eating problems were the dependent variables.
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3. Results 3.1. General findings Before addressing the main research issues, a number of general findings should be discussed. To begin with, questionnaires were generally reliable in terms of internal consistency (with most Cronbach’s alphas>.60). Further, as anticipated, girls displayed higher scores on scales referring to dieting and losing weight, whereas boys had higher scores on scales referring to becoming more muscular. 3.2. Correlates of body change strategies and eating problems Correlations between biological, psychological, and sociocultural factors on one hand, and body change strategies and eating problems on the other generally showed the predicted pattern. For example, in both genders, higher BMI was associated with stronger attempts to lose weight (rs between .46 and .52, Ps < .001). Further, high levels of body importance and body comparison were accompanied by stronger attempts to become more muscular (boys and girls; rs between .28 and .52, Ps < .001) and strategies to lose weight (girls; rs between .27 and .66, Ps < .001). In girls, lower levels of body satisfaction and self-esteem were associated with stronger attempts to lose weight and greater preoccupation with food (rs between .26 and .39, Ps < .001). Sociocultural factors were also significantly linked to body change strategies and eating problems (rs between .24 and .69, Ps < .005); that is, higher levels of encouragement by parents, peers, and media to lose weight or to increase muscles were accompanied by higher levels of corresponding body change strategies and eating problems. In boys, age and pubertal development were to some extent positively related to attempts to increase muscles (rs being .23 and .24, Ps < .005). 3.3. Relative contributions of various factors to body image, body change strategies, and eating problems 3.3.1. Boys Table 1 presents the results of stepwise regression analyses examining the relative contributions of various factors to body image, body change strategies, and eating problems in boys. Body image variables were predicted by various psychological and sociocultural factors, which accounted for between 23% and 27% of the total variance. More specifically, higher levels of self-esteem but lower levels of parent, peer, and media pressure to lose weight were accompanied by lower levels of body satisfaction. Note also that body importance made a unique contribution to body satisfaction and vice versa. The positive partial correlations indicate that higher levels of body importance were associated with higher levels of body satisfaction. As can be seen in Table 1, body comparison in boys was mainly predicted by parent, peer, and media pressure to become more muscular. As to the predictors of body change strategies and eating problems in boys, five remarks are in order. First, predictor variables together accounted for between 13% and 54% of the variance in boys’ body change and eating problems scores. Second, BMI uniquely contributed to BCI decrease body size and ChEAT dieting scores. As expected, higher BMI levels were associated with stronger attempts to lose weight. Third, in most regression equations, influences of parent, peer, and media made a significant contribution to most body change and eating problem scores. Fourth, of the body-image-related factors,
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Table 1 Results of the stepwise regression analysis predicting body image, body change strategies, and eating problems of boys Dependent
Predictors
Body satisfaction [ F(3,151) = 18.8, P < .001, R2=.27]
(1) (2) (3) (1) (2) (1) (2) (1) (2) (3) (1) (2) (1) (2) (3) (1) (2) (3) (4) (1) (2) (3) (1) (2) (1)
Body importance [ F(2,152) = 22.9, P < .001, R2=.23] Body comparison [ F(2,152) = 25.4, P < .001, R2=.25] BCI decrease body size [ F(3,151) = 43.6, P < .001, R2=.46] BCI increase muscle size [ F(2,152) = 29.7, P < .001, R2=.28] ChEAT total score [ F(3,151) = 47.5, P < .001, R2=.49] ChEAT dieting [ F(4,150) = 44.8, P < .001, R2=.54]
ChEAT muscle development [ F(3,151) = 37.3, P < .001, R2=.43] ChEAT social pressure to eat [ F(2,152) = 11.2, P < .001, R2=.13] ChEAT food preoccupation [ F(1,153) = 26.0, P < .001, R2=.15]
Self-esteem Body importance Parent and peer—Decrease weight Body satisfaction Body comparison Media—Increase muscle size Parent and peer—Increase muscle size Parent and peer—Decrease weight Media—Decrease weight BMI Parent and peer—Increase muscle size Body importance Body comparison Parent and peer—Increase muscle size BMI Parent and peer—Decrease weight Media—Decrease weight Body comparison BMI Parent and peer—Increase muscle size Body comparison Body importance Pubertal status Body comparison Body comparison
Partial r
t
.32 .33 .24 .42 .33 .30 .27 .58 .34 .30 .46 .29 .58 .42 .24 .65 .34 .23 .23 .53 .35 .30 .26 .25 .38
4.1 4.3 3.0 5.7 4.3 3.8 3.5 8.8 4.4 3.9 6.4 3.8 8.8 5.7 3.0 10.6 4.5 3.0 3.0 7.7 4.6 3.8 3.4 3.2 5.1
P < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .001 < .001 < .001 < .001 < .005 < .001 < .001 < .005 < .005 < .001 < .001 < .001 < .001 < .005 < .001
n = 155. The probability of the F to enter in the equation was set on P < .05/11.
body comparison (all ChEAT scores) and body importance (BCI increase muscle size and ChEAT muscle development) appeared to be unique predictors. Finally, pubertal status accounted for unique variance in ChEAT social pressure to eat scores. The partial correlation was negative and thus indicated that boys with a more proceeded pubertal development experienced less social pressure to eat. 3.3.2. Girls Table 2 displays the results of the stepwise regression analysis predicting body change strategies and eating problems in girls. As can be seen, body image variables were uniquely predicted by various factors, including self-esteem, BMI, and sociocultural influences. In total, predictor variables declared 20% to 56% of the variance in girls’ body image scores. In the regression equations predicting body change strategies and eating problems of girls, unique contributions were predominantly made by body comparison and influences of parent, peer, and media. Most relationships were as expected, and in total, significant predictors accounted for between 15% and 63% of the variance in BCI and ChEAT scores. However, two results require some further comment. First, perceived pressure of the media to increase muscle size made a significantly negative contribution to BCI decrease body size and ChEAT dieting. Apparently, higher
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Table 2 Results of the stepwise regression analysis predicting body image, body change strategies, and eating problems of girls Dependent
Predictors
Body satisfaction [ F(2,149) = 37.4, P < .001, R2=.33] Body importance [ F(1,150) = 36.4, P < .001, R2=.20] Body comparison [ F(3,148) = 63.8, P < .001, R2=.56] BCI decrease body size [ F(5,146) = 60.6, P < .001, R2=.68]
BCI increase muscle size [ F(2,149) = 32.0, P < .001, R2=.30] ChEAT total score [ F(3,148) = 71.1, P < .001, R2=.59] ChEAT dieting [ F(4,147) = 63.2, P < .001, R2=.63]
ChEAT muscle development [ F(2,149) = 44.1, P < .001, R2=.37] ChEAT social pressure to eat [ F(2,149) = 12.9, P < .001, R2=.15] ChEAT food preoccupation [ F(1,150) = 48.0, P < .001, R2=.24]
Partial r
t
(1) Self-esteem (2) BMI (1) Body comparison
.47 .32 .44
6.6 4.1 6.0
< .001 < .001 < .001
(1) (2) (3) (1) (2) (3) (4) (5) (1) (2) (1) (2) (3) (1) (2) (3) (4) (1) (2) (1) (2) (1)
.59 .38 .29 .68 .47 .31 .30 .25 .45 .35 .69 .40 .24 .69 .43 .32 .24 .52 .37 .37 .24 .49
8.8 5.0 3.7 11.3 6.5 3.9 3.9 3.1 6.2 4.5 11.8 5.3 3.1 10.6 5.8 4.0 2.9 7.4 4.9 4.9 3.0 6.9
< .001 < .001 < .001 < .001 < .001 < .001 < .005 < .005 < .001 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001 < .001 < .001 < .005 < .001
Media—Decrease weight Body importance Self-esteem Media—Decrease weight Parent and peer—Decrease weight Body comparison Media—Increase muscle size BMI Body comparison Parent and peer—Increase muscle size Body comparison Parent and peer—Decrease weight Media—Decrease weight Media—Decrease weight Parent and peer—Decrease weight Media—Increase muscle size Body comparison Body comparison Parent and peer—Increase muscle size Body comparison BMI Body comparison
P
n = 152. The probability of the F to enter in the equation was set on P < .05/11.
levels of perceived media pressure to increase muscle size were accompanied by lower levels of attempts to decrease body weight. Second, BMI accounted for unique variance in BCI decrease body size and ChEAT social pressure to eat scores. Partial correlations were respectively positive
Fig. 1. Regression model for ChEAT muscle development scores of boys.
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Fig. 2. Regression model for ChEAT muscle development scores of girls.
and negative, indicating that higher BMI was accompanied by greater attempts to lose weight and less social pressure to eat. 3.4. Models of body change strategies in boys and girls Figs. 1–4 summarize the final regression models of the main body change strategies in boys and girls (i.e., losing weight and becoming more muscular). When predicting muscle development of boys, a model emerged in which sociocultural pressures to increase muscle size, body comparison, and body importance had either direct or indirect influences. Similar predictors were found in the model explaining girls’ attempts to become more muscular. Note, however, that in girls, sociocultural pressures to decrease weight were the main determinants of body comparison, which in turn had a positive effect on strategies to develop muscles.
Fig. 3. Regression model for ChEAT dieting scores of boys.
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Fig. 4. Regression model for BCI decrease body size scores of girls.
The models explaining strategies to lose weight were generally comparable for boys and girls. More specifically, in both genders, BMI, sociocultural pressure to decrease weight, and body comparison were the key elements. A number of differences were also observed. First, self-esteem played a role in the model of decreasing body size in girls. As can be seen in Fig. 4, low levels of self-esteem contributed to girls’ tendency to compare their body with others, which in turn was an important determinant of BCI decrease body size. Second, in boys, sociocultural influences to increase muscle size were a significant predictor of body comparison, whereas in girls, sociocultural pressures to decrease weight significantly determined this body-image-related psychological factor. Finally, in girls, media pressures to increase muscle size had a direct negative effect on BCI decrease body size.
4. Discussion The current study examined relationships between biological (age, pubertal status, and BMI), psychological (self-esteem, body dissatisfaction, body importance, and body comparison), and sociocultural risk factors (influence of media, parents, and peers) on one hand, and body change strategies and disturbed eating attitudes and behaviors on the other in a sample of nonclinical adolescent boys and girls. The main findings can be catalogued as follows. First of all, as expected, boys displayed higher levels of attempts to become more muscular, whereas girls showed a stronger tendency for strategies to lose weight. Second, results demonstrated that biological, psychological, and sociocultural influences made unique and significant contributions to various body image and body change/eating problem variables. Third and finally, hierarchical regression analyses yielded theoretically meaningful models for the main body change strategies in boys and girls.
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In keeping with previous studies, BMI was found to be a consistent predictor of boys’ and girls’ attempts to lose weight (e.g., Holt & Ricciardelli, 2002; Neumark-Sztainer et al., 1999). The influence of the other biological factors, age and pubertal status, appeared marginal. Although age and pubertal development were to a certain extent positively related to attempts to become more muscular in boys, these variables did not explain unique variance in this type of body change strategy. Meanwhile, it may well be the case that the timing (i.e., age of onset) of the pubertal development is crucial for the development of body change strategies and eating problems (e.g., Ackard & Peterson, 2001; StriegelMoore et al., 2001). It is well conceivable that a too early or too late onset results in a deviation from the normal, age-appropriate body shape, which may have a negative impact on youths’ body image and, in its wake, may enhance body change strategies and eating problems. Only in girls did self-esteem appear to be a consistent correlate of strategies to lose weight (i.e., BCI decrease body size and ChEAT dieting). Moreover, the results of the hierarchical regression analyses suggest that self-esteem only has an indirect influence on girls’ body change strategies; that is, evidence emerged for a model in which self-esteem negatively contributed to body comparison, which in turn enhanced strategies to lose weight. Body-image-related psychological factors were in a theoretically meaningful way connected to body change strategies; that is, higher levels of body change strategies were associated with lower levels of body satisfaction (girls) and higher levels of body importance and body comparison (boys and girls). Further, it should be noted that in boys, body-image-related variables were most clearly connected to strategies to develop muscles; whereas in girls, these variables were most convincingly related to strategies to decrease weight. Surprisingly, while the results of the regression analyses indicated that body comparison appeared to be the most important body-image-related variable, none of the models included body satisfaction—a finding which is not in keeping with previous research (Ricciardelli & McCabe, 2001a, 2003). Note, however, that the current investigation was the first to include body satisfaction, body importance, and body comparison, hence having made it possible to study the relative contributions of these body-image-related factors. In line with previous studies, sociocultural influences were also found to be significantly related to body change strategies and eating problems (Cusamano & Thompson, 2000; McCabe & Ricciardelli, 2003c; McCabe et al., 2002; Ricciardelli & McCabe, 2000, 2001c, 2003). In general, these relations were as hypothesized, although we also obtained some unexpected findings. For example, the regression model predicting strategies to lose weight in girls, included a direct path from media—increase muscle size to BCI decrease body size. The negative (partial) correlation coefficient indicated that high levels of perceived media pressure to increase muscle size were accompanied by lower attempts to lose weight. Because correlational analysis revealed a positive relationship between media—increase muscle size and BCI decrease body size (r=.34, P < .001), it seems most likely that this link reflects a statistical artifact, which occurred as a result from partialling out the influence of highly related, concurrent predictor variables. It should be acknowledged that the current study suffers from various limitations. More precisely, the present study was correlational in nature, only relied on adolescents’ self-report, included no diagnostic interview instrument for assessing ‘clinical’ eating problems, and neglected a number of other potential risk factors for body change strategies and eating problems in youths (e.g., Lieberman, Gauvin, Bukowski, & White, 2001; McCabe et al., 2002; Ricciardelli & McCabe, 2001c). Despite these shortcomings, the data support previous findings in this research area and seem to suggest that body change strategies and eating problems in adolescents are determined by various biological, psychological, and psychosocial risk factors (e.g., Ricciardelli & McCabe, 2001a). Clearly, longitudinal research
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(e.g., McCabe & Ricciardelli, 2003a) is necessary to further evaluate the relative contributions of these variables in the development of eating disorders in youths.
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