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A prospective study of pressures from parents, peers, and the media on extreme weight change behaviors among adolescent boys and girls
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Behaviour Research and Therapy 43 (2005) 653–668 www.elsevier.com/locate/brat
A prospective study of pressures from parents, peers, and the media on extreme weight change behaviors among adolescent boys and girls Marita P. McCabe, Lina A. Ricciardelli School of Psychology, Deakin University, 221 Burwood Highway, Burwood, Melbourne, Vic. 3125, Australia Received 12 January 2004; received in revised form 10 May 2004; accepted 13 May 2004
Abstract The current study was designed to evaluate the role of sociocultural influences over a 16 month period on strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles among adolescent boys (n ¼ 344) and girls (n ¼ 246). All participants completed measures of body dissatisfaction, body image importance, strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles. Measures of perceived pressure to lose weight or increase muscles from mother, father, best male friend, best female friend and the media were also evaluated. Data were gathered on three occasions, 8 months apart. The results demonstrated that boys showed a decrease in strategies to lose weight and increase muscles over time, whereas girls showed an increase. Both boys and girls showed an increase in extreme weight loss strategies with girls demonstrating a greater increase than boys. The sociocultural influences generally were perceived by girls to relate to messages to lose weight, whereas for boys they were perceived to relate to increasing muscles. Messages from parents, particularly fathers, were strong predictors of both strategies to lose weight and increase muscles among boys, with the media and best male friend playing a limited role. For girls, the strongest influences were mothers and best female friends, with few influences from fathers or the media. The results of this study are discussed in terms of the importance of the various sociocultural influences in shaping body change strategies among young adolescent boys and girls, and the implications of these findings for intervention programs for adolescents. r 2004 Elsevier Ltd. All rights reserved. Keywords: Sociocultural influences; Lose weight; Increase muscles; Adolescent; Longitudinal Corresponding author. Tel.: +61-3-9244-6856; fax: 61-3-9244-6858.
E-mail address: [email protected] (M.P. McCabe). 0005-7967/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.brat.2004.05.004
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1. Introduction A substantial body of research has focused on the prevalence of extreme weight loss strategies among adolescent girls (e.g., Stice, 2001; Stormer & Thompson, 1996) and the sociocultural factors that are associated with these behaviors (e.g., Byely, Archibald, Graber, & Brooks-Gunn, 2000; Monteath & McCabe, 1997; Wertheim, Paxton, Schultz, & Muir, 1997). More recent literature has investigated weight change behaviors among adolescent boys, with a particular emphasis on increasing muscle and weight loss (Drewnowski & Yee, 1987; Furnham & Calnan, 1998; McCabe & Ricciardelli, 2001a; Pope, Phillips, & Olivardia, 2000; Ricciardelli & McCabe, 2001a, b). There has been a more limited examination of the sociocultural influences that are associated with these behaviors among adolescent boys (McCabe & Ricciardelli, 2003; Ricciardelli, McCabe, & Banfield, 2000; Vincent & McCabe, 2000). The present study was designed to determine the predictive role of sociocultural influences (parents, peers, media) on body image and behaviors to either lose weight or increase muscle, as well as the use of extreme weight loss behaviors at three time points over a 16 month time period among adolescent boys and girls. This study is focused on evaluating the social component of the biopsychosocial framework to explain health risk behaviors to achieve the ideal body endorsed by society (Ricciardelli & McCabe, 2004). This framework proposes that body image, disordered eating, strategies to increase muscles, as well as extreme weight change behaviors are shaped by biological, psychological and social factors. Biological factors include body mass index and pubertal timing, psychological factors include positive and negative affect and self-esteem, and social factors include perceived pressures from parents, peers and the media to alter weight and shape. This framework has received support for weight loss among adolescent girls, but there has been limited empirical investigation of the utility of this framework among adolescent boys. An earlier study examined the role of parents and peers on health risk behaviors of adolescents over an 8 month period (Ricciardelli & McCabe, 2003). However, this is the first study that has employed a prospective design to examine a broad range of sociocultural influences on health risk behaviors to either lose weight or increase muscles among adolescent boys. A number of previous longitudinal studies have examined the relationship between sociocultural influences and disordered eating among adolescent girls. For example, Field et al. (1999) conducted a 1 year follow-up of 6982 girls aged 6–14 years. The results indicated that importance of thinness to peers and wanting to look like females in the media were predictive of beginning to purge at least monthly. A later study by the same research team (Field et al., 2001) reported on a 1 year follow-up study of 6770 girls and 5287 boys between the ages of 9 and 14 years. The authors found that those boys and girls who were focused on looking like their samesex role models in the media were more likely to be concerned about their weight. Further, if fathers were perceived to view thinness or lack of fat as important, both boys and girls were more likely than their peers to become constant dieters. 1.1. Health risk behaviors Body image is influenced by the culturally defined ideal body type prescribed by society for females and males (McCabe & Ricciardelli, 2001a). For girls, the ideal is reflective of a slender prepubescent-like body. This is in contrast to the V-shaped masculine physique that is valued by
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males (Furnham & Calnan, 1998; McCabe & Ricciardelli, 2001a; McKay-Parks & Read, 1997; Pope et al., 2000). Pressure to attain the ideal body type has been used to explain the emergence and maintenance of body dissatisfaction among girls and boys. In particular, societal pressures have been reported to explain dissatisfaction with weight, a preoccupation with dieting and an increase in the incidence of eating disorders (Griffiths & McCabe, 2000; McCabe & Ricciardelli, 2001a; Powell & Kahn, 1995; Tiggemann & Rothblum, 1988). It would appear that these cognitions in relation to body image and dietary behaviors are at least partly due to the ideal body form promoted with the society. In a comprehensive review of the literature, Ricciardelli & McCabe (2004) demonstrated that the influence of sociocultural factors in the expression or maintenance of body dissatisfaction and health risk behaviors among adolescent boys remains relatively unexplored. However, one would expect that negative cognitions among boys in terms of the extent to which their body conforms to the ideal endorsed by society might also predict poor body image and the adoption of health risk behaviors. 1.2. Sociocultural influences Most of the past research on parental influence has focused on adolescent girls, and has primarily examined the association between parental pressures and weight loss, rather than strategies to increase muscles. Maternal encouragement to lose weight has been found to be associated with daughter’s reports of body dissatisfaction (Benedikt, Wertheim, & Love, 1998), while mothers of girls who displayed bulimic symptoms, as well as body dissatisfaction, have been found to be more critical of their daughter’s weight and attractiveness than mothers of control respondents (Pike & Rodin, 1991). Peers have also been found to transmit sociocultural messages that influence body image perceptions and weight concerns (Dunkley, Wertheim, & Paxton, 2001; McCabe & Ricciardelli, 2004a; McCabe, Ricciardelli & Finemore, 2002; Taylor et al., 1998; Vincent & McCabe, 2000; Wertheim et al., 1997). Peer discussions and modelling about weight-related issues have been found to further reinforce and perpetuate the importance of the perceived societal ideal among girls (Dunkley et al., 2001; Paxton, 1996) and boys (McCabe & Ricciardelli, 2003). Studies have generally concluded that the media transmits messages that result in high levels of body dissatisfaction among adolescent boys and girls (McCabe & Ricciardelli, 2001a; Ricciardelli et al., 2000; Thompson & Heinberg, 1999). The general consensus is that the media is an extremely powerful medium that promotes the thin ideal, which, in turn, contributes to body dissatisfaction in females. There also appears to be a growing media culture that is directed at the promotion of unnatural and unrealistic media representations of muscular male images (Pope, Olivardia, Gruber, & Borowiecki, 1999). While one study (Ricciardelli et al., 2000) found that adolescent boys perceived the media to have either a positive effect or no effect on their body image, other research has suggested that media images can lead to a preoccupation with wanting a more muscular body (Andersen & Di Domenico, 1992; Pope et al., 1999; Spitzer, Henderson, & Zivian, 1999). Few studies have examined the combined role of parents, peers, and the media on health risk behaviors. Studies that have examined the impact of a number of sociocultural influences on these behaviors in adolescent boys and girls have produced inconsistent findings. McCabe and Ricciardelli (2001a) found that mothers and peers were instrumental in encouraging adolescent
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girls to lose weight or increase muscle tone that would move them closer to the societal ideal. However, similar pressures were not perceived by adolescent boys. This supports earlier suggestions that boys may be less influenced by sociocultural pressures than girls (Andersen & Holman, 1997; Steen, Wadden, Foster, & Andersen, 1996). However, Ricciardelli et al. (2000) found that mothers and fathers act as role models and social reinforcers with regard to body change methods among adolescent boys. More specifically, boys who reported receiving messages from fathers to exercise reported engaging in more exercise to alter their body shape and the size of their muscles. Most of the longitudinal studies have examined weight loss behaviors among adolescent girls, with only minimal attention being devoted to a longitudinal examination of body dissatisfaction and weight loss behaviors in adolescent boys. Ricciardelli and McCabe (2003) conducted a longitudinal study over an 8 month period among adolescent boys and found that parents and peers played a limited role in predicting extreme body change strategies over this time period. This would suggest that sociocultural influences may play a role in extreme eating behaviors among adolescents. No studies have conducted a longitudinal evaluation of the impact of sociocultural influences on behaviors to increase muscle tone in adolescent girls, an area that may be of increasing concern for girls. In fact, recent research has suggested that both boys and girls are focused on a slim, muscular body, with the difference between the sexes being more level of muscles, rather than a quantitative difference (McCabe et al., 2002; Ricciardelli & McCabe, 2001a, Vartanian, Giant, & Passino, 2001). This is an important area of investigation, given the association between body change strategies, self-esteem and mental health of adolescent boys and girls (Ricciardelli & McCabe, 2001a). 1.3. Present study The aim of the present study was to investigate the evidence or the sociocultural factors in the biopsychosocial framework proposed by Ricciardelli & McCabe (2004) in predicting body image disturbance and health risk behaviors among adolescent boys and girls. It evaluated the role of sociocultural pressures (from parents, peers, media) on body image and health risk behaviors (lose weight, extreme weight loss strategies, or increase muscles) among adolescent boys and girls over a period of 16 months. This length of time was chosen to allow sufficient opportunity for the sociocultural messages to impact on both body image and body change strategies.
2. Method 2.1. Participants The participants in the study at time 1 were 494 boys (mean age=13.08 years) and 359 girls (mean age=12.89 years) enrolled in grade 7 at high school. The participants at time 2 were 438 boys (mean age=13.74 years) and 338 girls (mean age=13.61 years), and at time 3 the participants were 344 boys (mean age=14.49 years) and 246 girls (mean age=14.22 years). The analyses for the current paper are based on the responses of the 590 participants (344 boys, 246 girls) who completed the questionnaires on all three occasions. There were no significant
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differences in the body image or body change strategies of those participants who completed the questionnaire at times 1, 2, and 3, and those who completed the questionnaire at time 1 or 2 only. The participants were about equally divided between those who attended state schools or private schools, and those who attended single sex or coeducational schools. The schools were drawn from a wide range of socio-economic areas, and 83.5% of students were born in Australia. 2.2. Materials All students completed scales from the Body Image and Body Change Questionnaire (Ricciardelli & McCabe, 2002). These scales related to Body Dissatisfaction (10 items), Body Image Importance (10 items), Strategies to Lose Weight (six items), Extreme Weight Loss Behaviors (nine items), and Strategies to Increase Muscles (six items). Responses to all items were on a five-point likert scale from 1=never to 5=always. These scales emerged from both exploratory and confirmatory factor analysis, and demonstrate high levels of internal consistency (r4:75) (Ricciardelli & McCabe, 2002). Participants also completed five subscales from the Sociocultural Influences on Body Change Questionnaire (McCabe & Ricciardelli, 2001b). These scales related to Body Change Influences From Mother, Father, Best Male Friend, Best Female Friend and the Media. Each of these scales was comprised of seven items and evaluated perceived pressures to lose weight (3 items), or increase muscles (4 items). Responses to the items on each of the scales were scored on a five point likert scale from 1=never to 5=always. All of these scales have demonstrated high levels of internal consistency (r4:84) and have emerged from exploratory and confirmatory factor analyses (McCabe & Ricciardelli, 2001b). 2.3. Procedure Active consent was obtained from both parents and students to complete the study. The overall number of adolescents who returned their consent forms was 56%, but the participation rate varied from one school to another. For some schools the participation rate was 42%, for others it was 73%. This difference in response rate seemed to relate more to the procedures adopted by the school to secure the return of completed consent forms than to any other differences between the schools. There was no incentive provided for respondents to participate in the study. The questionnaire was completed in a group setting on three occasions, 8 months apart. At each testing occasion, respondents were asked to report their height and weight. Scales and tape measures were available for boys and girls who did not know these body dimensions.
3. Results Repeated measures analyses of variance were conducted to determine changes over time in body dissatisfaction and body change strategies among adolescent boys and girls. The means and standard deviations for all independent and dependent variables for times 1, 2 and 3 are summarized in Table 1.
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3.1. Body image and body change strategies There were strong intercorrelations between time 1, time 2 and time 3 measures of each variable, with time 1 and time 2 intercorrelations being greater than 0.38, and time 1 and time 3 intercorrelations being greater than 0.31. The results demonstrated that there was no overall change over time for body dissatisfaction or body image importance. There were also no overall gender differences in body dissatisfaction or body image importance. Interactions between gender and time in body dissatisfaction were also not significant. However, there was a significant interaction between gender and time for body image importance, F ð2; 538Þ ¼ 21:18, po:001, with boys showing a significant decrease in the importance of their body over time, but there were no changes in body image importance over time among girls. For strategies to lose weight there was no change over time. However, there were significant gender differences, F ð2; 538Þ ¼ 15:45, po:001, with girls being more likely to be engaging in strategies to lose weight than boys. There was also an interaction between gender and time for strategies to lose weight, Fð2; 358Þ ¼ 13:58, po:001, with boys showing a significant decrease and girls a significant increase in the use of these strategies over time. For extreme weight loss strategies, F ð2; 538Þ ¼ 5:25, po:01, which indicated that there was a significant increase in the use of these strategies over time. Girls were also more likely to engage in these strategies than boys, F ð2; 538Þ ¼ 6:77, po:001 There was also an interaction between gender and time for extreme weight loss strategies, F ð2; 538Þ ¼ 5:27, po:01, with both boys and girls showing a significant increase over time, but boys showing a significantly greater increase than girls. For strategies to increase muscles there was no significant change over time. However, boys were more likely to engage in these strategies than girls, F ð2; 538Þ ¼ 4:06, po:05. There was an interaction between gender and time for strategies to increase muscles, F ð2; 538Þ ¼ 3:48, po:05, with boys showing a significant decrease over time, and girls no change over time. 3.2. Sociocultural influences Repeated measures analyses of variance analyses were conducted to determine if there were changes in the nature of the sociocultural messages for adolescent boys and girls over time. The results demonstrated that there was no overall change over time in messages from mother to lose weight, no gender differences in these messages or no interaction between gender and time for these messages. There was an overall increase over time in messages from father to lose weight, F ð2; 539Þ ¼ 4:40, po:05, but there were no gender differences in these messages or no interaction between gender and time for these messages. There were no overall changes over time in messages from best male friend to lose weight, no gender differences in these messages, or no interaction between gender and time for these messages. For best female friend, there were no overall changes over time in the messages regarding losing weight, girls were more likely to perceive that their best female friend was pressuring them to lose weight F ð2; 539Þ ¼ 4:82, po:01, and there was a significant interaction between gender and time for the nature of the messages to boys and girls, F ð2; 539Þ ¼ 5:61, po:01, with there being no change in the messages to boys, but a significant increase in the messages to girls. There was an overall significant increase over time in the media messages to lose weight, F ð2; 539Þ ¼ 6:65, po:001, no gender differences in these messages and also there was no significant interaction between gender and time for these messages.
Table 1 Means and standard deviations of independent and dependent variables for adolescent males and females at time 1, 2 and 3 Variables
Time 1
c–d
po0:01.
Female mean (Standard deviation)
Male mean (Standard deviation)
Female mean (Standard deviation)
Male mean (Standard deviation)
Female mean (Standard deviation)
19.75 16.45 11.14 11.14
19.20 16.25 11.20 16.55
19.96 15.44 11.11 11.11
19.65 13.37 11.47 16.43
21.70 15.01 10.92 16.93
20.89 15.42 11.55 17.47
(3.14) (4.57)a (3.27) (3.27)c
(3.19) (3.51) (3.01) (4.71)d
(3.03) (4.88)b (3.66) (3.67)ac
(2.98) (3.55) (3.20) (5.49)ad
(5.80) (4.77) (3.36) (6.03)bc
(6.75) (4.45) (3.29) (6.37)bd
10.80 (4.83)c 12.24 (5.57)c
14.30 (5.93)d 8.68 (3.57)d
10.23 (4.94)c 11.53 (5.29)c
14.15 (6.37)ad 8.57 (3.75)d
10.06 (5.11)c 11.04 (4.97)c
15.27 (6.47)bd 8.31 (3.30)d
5.13 (1.41)
5.02 (1.33)
4.97 (1.47)
4.94 (1.27)
4.95 (1.39)
4.90 (1.35)
5.27 (1.54)
5.60 (1.69)
5.06 (1.56)
5.52 (1.67)
5.12 (1.51)
5.62 (1.77)
4.51 (1.20)
4.43 (0.77)
4.51 (1.30)
4.39 (0.97)
4.49 (1.14)
4.33 (0.94)
4.68 (1.28)
4.93 (1.28)
4.66 (1.33)
4.93 (1.42)
4.60 (1.16)a
5.13 (1.52)b
10.19 (3.34)
11.50 (2.92)
10.05 (3.74)
11.81 (3.15)
10.86 (3.46)
12.25 (2.85)
5.48 (1.71)
4.91 (1.26)
5.14 (1.49)
4.89 (1.29)
5.18 (1.62)
4.93 (1.45)
4.81 (1.37)
4.41 (0.76)
4.73 (1.38)
4.42 (0.94)
4.60 (1.18)
4.54 (1.11)
5.62 (1.92)
5.43 (1.35)
5.32 (1.90)
5.29 (1.38)
5.47 (1.82)
5.35 (1.58)
4.84 (1.52)
4.47 (0.85)
4.71 (1.49)
4.49 (1.12)
4.58 (1.15)
4.59 (1.16)
12.83 (3.81)a
12.79 (3.08)a
11.11 (3.97)b
10.62 (3.30)b
11.63 (3.67)b
10.96 (3.32)b
659
po0:05;
Male mean (Standard deviation)
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BMI Body image importance Body dissatisfaction Extreme weight loss behaviors Strategies to lose weight Strategies to increase muscles Messages from father to lose weight Messages from mother to lose weight Messages from best male friend to lose weight Messages from best female friend to lose weight Messages from media to lose weight Messages from father to increase muscles Messages from mother to increase muscles Messages from best male friend to increase muscles Messages from best female friend to increase muscles Messages from media to increase muscles
Time 2
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In relation to strategies to increase muscles, there were no overall changes over time for the messages from mothers. However, boys were more likely to perceive that mothers were pressing them to increase muscles, F ð2; 539Þ ¼ 6:17, po:01, and there was a significant interaction between gender and time for these messages, F ð2; 539Þ ¼ 5:25, po:01, with messages significantly decreasing over time for boys, but significantly increasing for girls. For fathers, there were no overall changes over time in messages about muscles, but boys were more likely to perceive that their fathers were encouraging to increase muscle, F ð2; 539Þ ¼ 5:54, po:01, and there was a significant interaction between gender and time for these messages, F ð2; 538Þ ¼ 4:80, po:01, with messages significantly decreasing for boys and showing little change for girls. For best male friend, there were no overall changes over time for messages about muscles, no gender differences in the nature of the messages, or significant interaction between time and gender for these messages. There were no overall changes over time in the nature of the messages from best female friend, but boys were more likely to perceive that they were receiving pressure to increase muscles, F ð2; 539Þ ¼ 5:76, po:01, and there was a significant interaction between gender and time for these messages, Fð2; 539Þ ¼ 6:67, po:001, with messages significantly decreasing for boys, but significantly increasing for girls. There were substantial decreases over time in the nature of the messages from the media, F ð2; 539Þ ¼ 72:02, po:001, but there were no perceived gender differences in these messages and no significant gender by time interaction for these messages. 3.3. Prediction of body image and body change strategies A series of hierarchical multiple regression analyses were conducted to determine the contribution of the sociocultural influences to body image and health risk behaviors for boys and girls at time 2 and 3. Analyses were conducted separately for boys and girls. Change scores in the sociocultural variables (i.e. between time 1 and time 2, or between time 1 and time 3) were used to predict change scores in the body image and health risk behaviors over the same period of time. Given the changes that are characteristic of the adolescent period, it was determined that a more meaningful representation of the longitudinal relationships between the variables would be obtained by examining the manner in which changes in the sociocultural variables predicted changes in the body image and body change variables over a shorter period of time (8 months) and a longer period of time (16 months). This method of analysing longitudinal data has been recommended as an appropriate technique by both Rogosa (1995) and Stoolmiller and Bank (1995). The independent variables in each analysis were change scores in messages from: mother, father, best male friend, best female friend, and the media to lose weight; mother, father, best male friend, best female friend, and the media to increase muscles. The dependent variables were change scores in body dissatisfaction, body image importance, strategies to lose weight, extreme weight loss strategies, and strategies to increase muscle. Analyses were conducted for change scores between time 1 and time 2, and between time 1 and time 3. 3.4. Time 1 to time 3 Boys: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 293Þ ¼ 0:89, p4:05; changes in body image importance, F ð10; 293Þ ¼ 0:90, p4:05, and changes in extreme weight loss behaviors, Fð10; 293Þ ¼ 1:08, p4:05. For changes in strategies to
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lose weight, F ð10; 293Þ ¼ 4:45, po0:001, R2 ¼ :13. The variables that provided unique variance to strategies to lose weight were pressures from father to lose weight, pressures from father to increase muscle, and pressures from the media to increase muscle. For changes in strategies to increase muscles, Fð10; 293Þ ¼ 6:18, po0:001, R2 ¼ :17. The variables that provided unique prediction to strategies to increase muscle were changes in pressures from mother to increase muscle, pressures from father to increase muscle, pressures from best male friend to increase muscle, and pressures from the media to increase muscle. See Tables 2–4 for a summary of the beta weights and t values for the regression analyses outlined above. Girls: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 227Þ ¼ 1:23, p4:05, and changes in body image importance, F ð10; 227Þ ¼ 0:92, p4:05. For changes in strategies to lose weight, F ð10; 227Þ ¼ 5:91, po:001, R2 ¼ :21. The variables that provided unique variance were changes in pressures from mother to lose weight, and pressures from father to increase muscle. For changes in extreme weight loss behaviors, F ð10; 227Þ ¼ 2:27, po0:01, R2 ¼ :09. The variables that provided unique prediction were changes in pressure from mother to lose weight, pressures from best male friend to lose weight, and pressures from mother to increase muscle. For changes in strategies to increase muscles, F ð10; 227Þ ¼ 2:64, po0:01, R2 ¼ :10. The variables that provided unique variance were changes in pressures from best female friend to increase muscles, and pressures from the media to increase muscles. See Tables 2–4 for a summary for the beta weights and t values for the regression equations. 3.5. Time 1 to time 3 Boys: Non-significant results were obtained for changes in body dissatisfaction, F(10, 293)=0.40, p>0.05; changes in body image importance, F ð10; 293Þ ¼ 1:03, p4:05; changes in extreme weight loss strategies, F ð10; 293Þ ¼ 1:60, p4:05. For changes in strategies to lose weight Table 2 Summary of beta weights for regression analyses for weight loss Time 1 to time 2 Boys
Lose weight Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
po0:001.
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.08 0.23*** 0.10 0.07 0.03 0.13 0.17* 0.11 0.10 0.21**
1.12 3.56*** 1.52 0.99 0.48 1.82 2.44* 1.75 1.28 2.96**
0.31*** 0.11 0.06 0.11 0.13 0.05 0.15** 0.05 0.01 0.03
4.53*** 1.55 0.87 1.58 1.71 0.83 2.80** 0.72 0.20 0.34
0.08 0.23 0.01 0.04 0.16* 0.08 0.11 0.08 0.01 0.02
1.25 3.58*** 0.14 0.54 2.24* 0.97 1.50 1.25 0.09 0.27
0.21** 0.02 0.05 0.10 0.14 0.09 0.02 0.04 0.03 0.04
2.73** 0.23 0.70 1.38 1.85 1.25 0.23 -0.61 0.45 0.58
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Table 3 Summary of beta weights for regression analyses for extreme weight loss Time 1 to time 2 Boys
Extreme weight loss Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.10 0.05 0.05 0.06 0.14 0.07 0.01 0.02 0.01 0.13
1.30 0.76 0.80 0.78 2.12 0.91 0.09 0.30 0.07 1.70
0.16* 0.01 0.14* 0.05 0.09 0.26*** 0.10 0.02 0.10 0.02
2.19* 0.08 2.04* 0.72 1.12 3.37*** 1.50 0.35 1.40 0.20
0.07 0.10 0.08 0.06 0.07 0.03 0.02 0.11 0.05 0.10
1.06 1.56 1.10 0.80 0.90 0.39 0.23 1.58 0.68 1.41
0.21** 0.01 0.07 0.16* 0.04 0.00 0.04 0.11 0.13* 0.07
2.87** 0.08 0.96 2.31* 0.48 0.00 0.55 1.55 2.35* 0.97
po0:001.
Table 4 Summary of beta weights for regression analyses for strategies to increase muscles Time 1 to time 2 Boys
Increase muscles Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.06 0.06 0.00 0.01 0.05 0.16* 0.15* 0.16* 0.06 0.15*
0.88 0.97 0.02 0.15 0.70 2.55* 2.38* 2.58* 0.86 2.18*
0.05 0.04 0.07 0.05 0.03 0.01 0.10 0.07 0.21** 0.19*
0.67 0.57 1.01 0.72 0.33 0.17 1.56 1.00 2.81** 2.29*
0.02 0.04 0.07 0.04 0.11 0.20** 0.15* 0.21** 0.01 0.02
0.23 0.61 1.14 0.56 1.65 2.76** 2.15* 2.87** 0.16 0.23
0.09 0.03 0.08 0.03 0.13 0.19** 0.00 0.09 0.19** 0.03
1.18 0.36 1.16 0.45 1.77 2.78** 0.02 1.25 2.71** 0.44
po0:001.
F ð10; 293Þ ¼ 2:66, po0:01, R2 ¼ :08. The variables that provide unique variance were changes in pressures from father to lose weight, and pressures from the media to lose weight. For changes in strategies to increase muscles, Fð10; 293Þ ¼ 8:01, po0:001, R2 ¼ :22. The variables that provided unique variance were changes in pressures from mother to increase muscle, pressures from father to increase muscle, and pressure from best male friend to increase muscle. See Tables 2–4 for a summary of the beta weight and t values for the regression equations.
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Girls: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 227Þ ¼ 1:41, p4:05, and changes in body image importance, F ð10; 227Þ ¼ 0:76, p4:05. For changes in strategies to lose weight, F ð10; 227Þ ¼ 2:08, po0:05, R2 ¼ :08. The variable that provided unique variance was changes in pressures from mother to lose weight. For changes in extreme weight loss strategies, F ð10; 227Þ ¼ 3:63, po0:001, R2 ¼ :14. The variables that provided unique variance were changes in pressures from mother to lose weight, pressures from best female friend to lose weight, and pressures from best female friend to increase muscles. For changes in strategies to increase muscles, F ð10; 227Þ ¼ 3:26, po:001, R2 ¼ :13. The variables that provided unique variance were changes in pressures from mother to increase muscles, and pressures from best female friend to increase muscles. See Tables 2–4 for a summary of the beta weight and t values for the regression equations.
4. Discussion This longitudinal study was designed to determine changes over time in the body image and health risk behaviors of adolescent boys and girls. Further, it examined the role of sociocultural pressures (i.e., perceived pressures from mother, father, best male friend, best female friend, media) to both lose weight and increase muscle, on the body image and health risk behaviors of both adolescent boys and girls. The results demonstrated that as expected, at all points in time, girls were more likely to adopt strategies to lose weight and extreme weight loss strategies, whereas boys were more likely to adopt strategies to increase muscles. There were also some changes in the body image and body change strategies adopted by boys and girls over this 16 month period. Results of particular clinical concern are the findings that both boys and girls increased their use of extreme body change strategies over time, with girls showing a greater increase than boys. Girls appear to learn at an early age about the sociocultural ideal for girls (Thompson & Heinberg, 1999). As a result, their body image is influenced by this ideal, and they adopt body change strategies that may be injurious to their health to achieve this ideal. As they progress through adolescence, girls may become more aware of this sociocultural ideal and so increase their attempts to achieve it. In contrast, boys showed a reduction in the importance of their body as they progressed through adolescence, and so they were less likely to attempt to lose weight, or increase muscles, and also demonstrated a smaller increase than girls in extreme body change strategies to achieve their ideal body. As boys reach puberty, their bodies are more likely to conform to the sociocultural ideal for boys, and so it may be less necessary for them to engage in these health risk behaviors to achieve this ideal. However, since boys in this study were only, on average, 14.49 years at the completion of the study we are not able to draw conclusions about the focus on muscles among boys later in adolescence. In fact, previous research would suggest that there is an increased focus on muscles among late adolescent boys (see McCabe & Ricciardelli, 2004b, for a review). It is interesting to examine the source of the messages regarding the ideal body for boys and girls. Consistent with previous research (e.g., McCabe et al., 2002; Vincent & McCabe, 2000), the perceived messages to lose weight from peers and the media were higher for girls than boys, whereas the perceived messages from mothers, fathers and female friends to increase muscles were
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higher for boys than for girls. It is important to note that these are perceived messages from the sociocultural forces and the nature of these messages may say more about the body focus of the adolescents, than the actual nature of the messages. The results demonstrated that there were very few changes over time in the nature of the perceived messages from parents, peers or the media to lose weight. However, perceived messages from female friends and the media increased for girls, and perceived messages from the media increased for boys. Thus, friends and the media are clearly targets for prevention programs for adolescent girls, as it would seem that these are the sociocultural influences that are perceived to increase their messages over the adolescent period for girls to lose weight in order to conform to the sociocultural ideal for girls. This change in the level of these perceived messages may be due to the increased focus of girls on achieving this ideal body as they progress through adolescence. Changes over time in the perceived sociocultural messages related to increasing muscles present a different picture. Mothers, fathers, female friends and the media were perceived to decrease their messages regarding muscle size for boys. For girls, mothers and best female friend showed a perceived increase in these messages over time, whereas the media showed a decrease. Despite these changes in messages over time, the sociocultural messages regarding increased muscles were generally higher for boys than for girls. These stronger messages may explain the higher use of strategies to increase muscles among boys, or may be due to boys being more likely to pick up on these messages due to their greater focus on their muscles. These results are somewhat surprising, particularly in relation to girls. They would suggest that girls may be receiving messages that relate to the achievement of a slim toned body, with muscular definition, rather than a slim body alone that has been proposed from previous research (e.g., Byely et al., 2000). A new standard for the ideal body form may be becoming established for adolescent girls. This proposal is certainly consistent with recent research studies (McCabe et al., 2002; Vartanian et al., 2001). Much of the previous research has not investigated the desire for a muscular body in girls, so this has not been highlighted as an area for concern. However, the current findings would suggest that both adolescent boys and girls may be experiencing pressures to increase their muscles. Clearly, further research is needed to determine if girls are now more focused on body tone as well as obtaining a slim body. If this is the case, intervention programs for adolescent boys and girls need to be designed to focus on both strategies to lose weight as well as increasing muscles. The results from the regression analyses demonstrated that changes in sociocultural messages did not predict changes in body image for either boys or girls. These results applied for both the 8 and the 16 month period. These results, combined with the results reported earlier in the discussion, would seem to suggest that body image (both body dissatisfaction and body image importance) is a reasonably stable dimension of the self-image of adolescent boys and girls. It would appear that body image may be part of adolescents’ broader self-image, and not readily changed by messages from sociocultural influences. Fathers were an important influence for boys in terms of both losing weight and increasing muscles. The media also played a strong role in weight loss strategies for boys. It is interesting to note that changes in perceived pressures from both parents and the best male friend predicted changes in strategies to build muscles for boys. These results are consistent with findings from past cross-sectional studies (e.g., Ricciardelli & McCabe, 2003). Both parents and male peers may be particularly focused on sending messages about building muscles to adolescent boys, so that the messages they generate lead adolescent boys to adopt strategies that help them achieve the ideal
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body that is endorsed by society. Messages from female friends did not impact on body image or body change strategies for adolescent boys. During early adolescence (i.e., 13–14 years of age), the opposite sex may not influence the way boys feel about their body, or the strategies they adopt to alter their body. It is important to investigate these same relationships among older adolescent boys, since messages from female friends may have a greater impact during late adolescence. Consistent with the findings for adolescent boys, messages from both parents and peers predicted changes in body change strategies among adolescent girls. Both parents and their best female friends were the most consistent predictor of health risk behaviors. The central role played by messages from parents in shaping a broad range of health risk behaviors among young adolescent girls are demonstrated by these findings: they impacted on losing weight, adopting extreme strategies to lose weight, and even strategies to increase muscles. These results are consistent with previous findings in relation to the role of mothers in shaping strategies to lose weight among adolescent girls (e.g., Benedikt, et al., 1998). They extend these findings to indicate that mothers also play a role in the adoption of strategies to increase muscles among adolescent girls. Consistent with previous studies (e.g., Paxton, Schutz, Wertheim, & Muir, 1999), the results demonstrate the importance of female friends in shaping weight loss, and extreme weight loss strategies. In addition, they indicate that perceived messages from female friends predict strategies to increase muscles. If these results are replicated in other studies, prevention programs for girls may need to be expanded to focus on strategies to increase muscles, as this may be an emerging area of concern among adolescent girls in terms of their health risk behaviors. Messages from opposite-sex peers played a limited role in shaping the body change strategies of both adolescent boys and girls. Early adolescents may not yet have tuned into these messages, and they may be still focused on messages from their parents and same-sex peers. Given the changes that occur in friendship patterns as boys and girls move through adolescence, parents would be expected to play a less central role and opposite-sex peers a more central role as adolescence progresses. A limitation of the current study is that it was reliant upon self-reported questionnaire data. Certainly, research conducted by Stice, Fisher and Lowe (2004) would suggest that despite the correlations between different questionnaire measures of dietary restraint, there is a lack of concordance between self reported dietary restraint and caloric intake. These findings were obtained for female undergraduate students and females frequenting a fast food outlet, and were consistent across the four studies reported in the Stice et al.’s paper. Future studies need to also utilize interview techniques to obtain a better understanding, not only on the nature of the relationship between sociocultural influences and health risk behaviors, but also of the meaning placed on the messages from the sociocultural agents. In this way, it will be possible to better understand the cognitive interpretation placed on these perceived messages. It is also important to determine the actual nature of the messages generated by the sociocultural agents. This will identify any interpretative bias, which may be occurring among adolescents. These data are important to inform any prevention or intervention program to modify cognitions that are focused on achieving an unrealistic body shape, so as to prevent high levels of body dissatisfaction and the adoption of health risk behaviors. The results of this study demonstrate that perceived messages from mothers, fathers and samesex peers play an important role in shaping strategies to both lose weight and increase muscle tone among adolescent boys and girls. Further studies need to explore the relationship between the
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actual and perceived messages from the various sources. Although boys are more focused on increasing muscles, and girls are more focused on losing weight, the results in this study suggest that both boys and girls are striving to achieve a slim, toned body. Rather than the ideal body for the different sexes being radically different from one another, the difference may only be one of degree. These findings have implications for the types of prevention and intervention programs developed to address disordered eating and extreme strategies to increase muscles for adolescents. These programs need to address the full range of health risk behaviors that are adopted to achieve the ideal body endorsed by the sociocultural influences investigated in this study.
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Behaviour Research and Therapy 43 (2005) 653–668 www.elsevier.com/locate/brat
A prospective study of pressures from parents, peers, and the media on extreme weight change behaviors among adolescent boys and girls Marita P. McCabe, Lina A. Ricciardelli School of Psychology, Deakin University, 221 Burwood Highway, Burwood, Melbourne, Vic. 3125, Australia Received 12 January 2004; received in revised form 10 May 2004; accepted 13 May 2004
Abstract The current study was designed to evaluate the role of sociocultural influences over a 16 month period on strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles among adolescent boys (n ¼ 344) and girls (n ¼ 246). All participants completed measures of body dissatisfaction, body image importance, strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles. Measures of perceived pressure to lose weight or increase muscles from mother, father, best male friend, best female friend and the media were also evaluated. Data were gathered on three occasions, 8 months apart. The results demonstrated that boys showed a decrease in strategies to lose weight and increase muscles over time, whereas girls showed an increase. Both boys and girls showed an increase in extreme weight loss strategies with girls demonstrating a greater increase than boys. The sociocultural influences generally were perceived by girls to relate to messages to lose weight, whereas for boys they were perceived to relate to increasing muscles. Messages from parents, particularly fathers, were strong predictors of both strategies to lose weight and increase muscles among boys, with the media and best male friend playing a limited role. For girls, the strongest influences were mothers and best female friends, with few influences from fathers or the media. The results of this study are discussed in terms of the importance of the various sociocultural influences in shaping body change strategies among young adolescent boys and girls, and the implications of these findings for intervention programs for adolescents. r 2004 Elsevier Ltd. All rights reserved. Keywords: Sociocultural influences; Lose weight; Increase muscles; Adolescent; Longitudinal Corresponding author. Tel.: +61-3-9244-6856; fax: 61-3-9244-6858.
E-mail address: [email protected] (M.P. McCabe). 0005-7967/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.brat.2004.05.004
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1. Introduction A substantial body of research has focused on the prevalence of extreme weight loss strategies among adolescent girls (e.g., Stice, 2001; Stormer & Thompson, 1996) and the sociocultural factors that are associated with these behaviors (e.g., Byely, Archibald, Graber, & Brooks-Gunn, 2000; Monteath & McCabe, 1997; Wertheim, Paxton, Schultz, & Muir, 1997). More recent literature has investigated weight change behaviors among adolescent boys, with a particular emphasis on increasing muscle and weight loss (Drewnowski & Yee, 1987; Furnham & Calnan, 1998; McCabe & Ricciardelli, 2001a; Pope, Phillips, & Olivardia, 2000; Ricciardelli & McCabe, 2001a, b). There has been a more limited examination of the sociocultural influences that are associated with these behaviors among adolescent boys (McCabe & Ricciardelli, 2003; Ricciardelli, McCabe, & Banfield, 2000; Vincent & McCabe, 2000). The present study was designed to determine the predictive role of sociocultural influences (parents, peers, media) on body image and behaviors to either lose weight or increase muscle, as well as the use of extreme weight loss behaviors at three time points over a 16 month time period among adolescent boys and girls. This study is focused on evaluating the social component of the biopsychosocial framework to explain health risk behaviors to achieve the ideal body endorsed by society (Ricciardelli & McCabe, 2004). This framework proposes that body image, disordered eating, strategies to increase muscles, as well as extreme weight change behaviors are shaped by biological, psychological and social factors. Biological factors include body mass index and pubertal timing, psychological factors include positive and negative affect and self-esteem, and social factors include perceived pressures from parents, peers and the media to alter weight and shape. This framework has received support for weight loss among adolescent girls, but there has been limited empirical investigation of the utility of this framework among adolescent boys. An earlier study examined the role of parents and peers on health risk behaviors of adolescents over an 8 month period (Ricciardelli & McCabe, 2003). However, this is the first study that has employed a prospective design to examine a broad range of sociocultural influences on health risk behaviors to either lose weight or increase muscles among adolescent boys. A number of previous longitudinal studies have examined the relationship between sociocultural influences and disordered eating among adolescent girls. For example, Field et al. (1999) conducted a 1 year follow-up of 6982 girls aged 6–14 years. The results indicated that importance of thinness to peers and wanting to look like females in the media were predictive of beginning to purge at least monthly. A later study by the same research team (Field et al., 2001) reported on a 1 year follow-up study of 6770 girls and 5287 boys between the ages of 9 and 14 years. The authors found that those boys and girls who were focused on looking like their samesex role models in the media were more likely to be concerned about their weight. Further, if fathers were perceived to view thinness or lack of fat as important, both boys and girls were more likely than their peers to become constant dieters. 1.1. Health risk behaviors Body image is influenced by the culturally defined ideal body type prescribed by society for females and males (McCabe & Ricciardelli, 2001a). For girls, the ideal is reflective of a slender prepubescent-like body. This is in contrast to the V-shaped masculine physique that is valued by
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males (Furnham & Calnan, 1998; McCabe & Ricciardelli, 2001a; McKay-Parks & Read, 1997; Pope et al., 2000). Pressure to attain the ideal body type has been used to explain the emergence and maintenance of body dissatisfaction among girls and boys. In particular, societal pressures have been reported to explain dissatisfaction with weight, a preoccupation with dieting and an increase in the incidence of eating disorders (Griffiths & McCabe, 2000; McCabe & Ricciardelli, 2001a; Powell & Kahn, 1995; Tiggemann & Rothblum, 1988). It would appear that these cognitions in relation to body image and dietary behaviors are at least partly due to the ideal body form promoted with the society. In a comprehensive review of the literature, Ricciardelli & McCabe (2004) demonstrated that the influence of sociocultural factors in the expression or maintenance of body dissatisfaction and health risk behaviors among adolescent boys remains relatively unexplored. However, one would expect that negative cognitions among boys in terms of the extent to which their body conforms to the ideal endorsed by society might also predict poor body image and the adoption of health risk behaviors. 1.2. Sociocultural influences Most of the past research on parental influence has focused on adolescent girls, and has primarily examined the association between parental pressures and weight loss, rather than strategies to increase muscles. Maternal encouragement to lose weight has been found to be associated with daughter’s reports of body dissatisfaction (Benedikt, Wertheim, & Love, 1998), while mothers of girls who displayed bulimic symptoms, as well as body dissatisfaction, have been found to be more critical of their daughter’s weight and attractiveness than mothers of control respondents (Pike & Rodin, 1991). Peers have also been found to transmit sociocultural messages that influence body image perceptions and weight concerns (Dunkley, Wertheim, & Paxton, 2001; McCabe & Ricciardelli, 2004a; McCabe, Ricciardelli & Finemore, 2002; Taylor et al., 1998; Vincent & McCabe, 2000; Wertheim et al., 1997). Peer discussions and modelling about weight-related issues have been found to further reinforce and perpetuate the importance of the perceived societal ideal among girls (Dunkley et al., 2001; Paxton, 1996) and boys (McCabe & Ricciardelli, 2003). Studies have generally concluded that the media transmits messages that result in high levels of body dissatisfaction among adolescent boys and girls (McCabe & Ricciardelli, 2001a; Ricciardelli et al., 2000; Thompson & Heinberg, 1999). The general consensus is that the media is an extremely powerful medium that promotes the thin ideal, which, in turn, contributes to body dissatisfaction in females. There also appears to be a growing media culture that is directed at the promotion of unnatural and unrealistic media representations of muscular male images (Pope, Olivardia, Gruber, & Borowiecki, 1999). While one study (Ricciardelli et al., 2000) found that adolescent boys perceived the media to have either a positive effect or no effect on their body image, other research has suggested that media images can lead to a preoccupation with wanting a more muscular body (Andersen & Di Domenico, 1992; Pope et al., 1999; Spitzer, Henderson, & Zivian, 1999). Few studies have examined the combined role of parents, peers, and the media on health risk behaviors. Studies that have examined the impact of a number of sociocultural influences on these behaviors in adolescent boys and girls have produced inconsistent findings. McCabe and Ricciardelli (2001a) found that mothers and peers were instrumental in encouraging adolescent
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girls to lose weight or increase muscle tone that would move them closer to the societal ideal. However, similar pressures were not perceived by adolescent boys. This supports earlier suggestions that boys may be less influenced by sociocultural pressures than girls (Andersen & Holman, 1997; Steen, Wadden, Foster, & Andersen, 1996). However, Ricciardelli et al. (2000) found that mothers and fathers act as role models and social reinforcers with regard to body change methods among adolescent boys. More specifically, boys who reported receiving messages from fathers to exercise reported engaging in more exercise to alter their body shape and the size of their muscles. Most of the longitudinal studies have examined weight loss behaviors among adolescent girls, with only minimal attention being devoted to a longitudinal examination of body dissatisfaction and weight loss behaviors in adolescent boys. Ricciardelli and McCabe (2003) conducted a longitudinal study over an 8 month period among adolescent boys and found that parents and peers played a limited role in predicting extreme body change strategies over this time period. This would suggest that sociocultural influences may play a role in extreme eating behaviors among adolescents. No studies have conducted a longitudinal evaluation of the impact of sociocultural influences on behaviors to increase muscle tone in adolescent girls, an area that may be of increasing concern for girls. In fact, recent research has suggested that both boys and girls are focused on a slim, muscular body, with the difference between the sexes being more level of muscles, rather than a quantitative difference (McCabe et al., 2002; Ricciardelli & McCabe, 2001a, Vartanian, Giant, & Passino, 2001). This is an important area of investigation, given the association between body change strategies, self-esteem and mental health of adolescent boys and girls (Ricciardelli & McCabe, 2001a). 1.3. Present study The aim of the present study was to investigate the evidence or the sociocultural factors in the biopsychosocial framework proposed by Ricciardelli & McCabe (2004) in predicting body image disturbance and health risk behaviors among adolescent boys and girls. It evaluated the role of sociocultural pressures (from parents, peers, media) on body image and health risk behaviors (lose weight, extreme weight loss strategies, or increase muscles) among adolescent boys and girls over a period of 16 months. This length of time was chosen to allow sufficient opportunity for the sociocultural messages to impact on both body image and body change strategies.
2. Method 2.1. Participants The participants in the study at time 1 were 494 boys (mean age=13.08 years) and 359 girls (mean age=12.89 years) enrolled in grade 7 at high school. The participants at time 2 were 438 boys (mean age=13.74 years) and 338 girls (mean age=13.61 years), and at time 3 the participants were 344 boys (mean age=14.49 years) and 246 girls (mean age=14.22 years). The analyses for the current paper are based on the responses of the 590 participants (344 boys, 246 girls) who completed the questionnaires on all three occasions. There were no significant
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differences in the body image or body change strategies of those participants who completed the questionnaire at times 1, 2, and 3, and those who completed the questionnaire at time 1 or 2 only. The participants were about equally divided between those who attended state schools or private schools, and those who attended single sex or coeducational schools. The schools were drawn from a wide range of socio-economic areas, and 83.5% of students were born in Australia. 2.2. Materials All students completed scales from the Body Image and Body Change Questionnaire (Ricciardelli & McCabe, 2002). These scales related to Body Dissatisfaction (10 items), Body Image Importance (10 items), Strategies to Lose Weight (six items), Extreme Weight Loss Behaviors (nine items), and Strategies to Increase Muscles (six items). Responses to all items were on a five-point likert scale from 1=never to 5=always. These scales emerged from both exploratory and confirmatory factor analysis, and demonstrate high levels of internal consistency (r4:75) (Ricciardelli & McCabe, 2002). Participants also completed five subscales from the Sociocultural Influences on Body Change Questionnaire (McCabe & Ricciardelli, 2001b). These scales related to Body Change Influences From Mother, Father, Best Male Friend, Best Female Friend and the Media. Each of these scales was comprised of seven items and evaluated perceived pressures to lose weight (3 items), or increase muscles (4 items). Responses to the items on each of the scales were scored on a five point likert scale from 1=never to 5=always. All of these scales have demonstrated high levels of internal consistency (r4:84) and have emerged from exploratory and confirmatory factor analyses (McCabe & Ricciardelli, 2001b). 2.3. Procedure Active consent was obtained from both parents and students to complete the study. The overall number of adolescents who returned their consent forms was 56%, but the participation rate varied from one school to another. For some schools the participation rate was 42%, for others it was 73%. This difference in response rate seemed to relate more to the procedures adopted by the school to secure the return of completed consent forms than to any other differences between the schools. There was no incentive provided for respondents to participate in the study. The questionnaire was completed in a group setting on three occasions, 8 months apart. At each testing occasion, respondents were asked to report their height and weight. Scales and tape measures were available for boys and girls who did not know these body dimensions.
3. Results Repeated measures analyses of variance were conducted to determine changes over time in body dissatisfaction and body change strategies among adolescent boys and girls. The means and standard deviations for all independent and dependent variables for times 1, 2 and 3 are summarized in Table 1.
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3.1. Body image and body change strategies There were strong intercorrelations between time 1, time 2 and time 3 measures of each variable, with time 1 and time 2 intercorrelations being greater than 0.38, and time 1 and time 3 intercorrelations being greater than 0.31. The results demonstrated that there was no overall change over time for body dissatisfaction or body image importance. There were also no overall gender differences in body dissatisfaction or body image importance. Interactions between gender and time in body dissatisfaction were also not significant. However, there was a significant interaction between gender and time for body image importance, F ð2; 538Þ ¼ 21:18, po:001, with boys showing a significant decrease in the importance of their body over time, but there were no changes in body image importance over time among girls. For strategies to lose weight there was no change over time. However, there were significant gender differences, F ð2; 538Þ ¼ 15:45, po:001, with girls being more likely to be engaging in strategies to lose weight than boys. There was also an interaction between gender and time for strategies to lose weight, Fð2; 358Þ ¼ 13:58, po:001, with boys showing a significant decrease and girls a significant increase in the use of these strategies over time. For extreme weight loss strategies, F ð2; 538Þ ¼ 5:25, po:01, which indicated that there was a significant increase in the use of these strategies over time. Girls were also more likely to engage in these strategies than boys, F ð2; 538Þ ¼ 6:77, po:001 There was also an interaction between gender and time for extreme weight loss strategies, F ð2; 538Þ ¼ 5:27, po:01, with both boys and girls showing a significant increase over time, but boys showing a significantly greater increase than girls. For strategies to increase muscles there was no significant change over time. However, boys were more likely to engage in these strategies than girls, F ð2; 538Þ ¼ 4:06, po:05. There was an interaction between gender and time for strategies to increase muscles, F ð2; 538Þ ¼ 3:48, po:05, with boys showing a significant decrease over time, and girls no change over time. 3.2. Sociocultural influences Repeated measures analyses of variance analyses were conducted to determine if there were changes in the nature of the sociocultural messages for adolescent boys and girls over time. The results demonstrated that there was no overall change over time in messages from mother to lose weight, no gender differences in these messages or no interaction between gender and time for these messages. There was an overall increase over time in messages from father to lose weight, F ð2; 539Þ ¼ 4:40, po:05, but there were no gender differences in these messages or no interaction between gender and time for these messages. There were no overall changes over time in messages from best male friend to lose weight, no gender differences in these messages, or no interaction between gender and time for these messages. For best female friend, there were no overall changes over time in the messages regarding losing weight, girls were more likely to perceive that their best female friend was pressuring them to lose weight F ð2; 539Þ ¼ 4:82, po:01, and there was a significant interaction between gender and time for the nature of the messages to boys and girls, F ð2; 539Þ ¼ 5:61, po:01, with there being no change in the messages to boys, but a significant increase in the messages to girls. There was an overall significant increase over time in the media messages to lose weight, F ð2; 539Þ ¼ 6:65, po:001, no gender differences in these messages and also there was no significant interaction between gender and time for these messages.
Table 1 Means and standard deviations of independent and dependent variables for adolescent males and females at time 1, 2 and 3 Variables
Time 1
c–d
po0:01.
Female mean (Standard deviation)
Male mean (Standard deviation)
Female mean (Standard deviation)
Male mean (Standard deviation)
Female mean (Standard deviation)
19.75 16.45 11.14 11.14
19.20 16.25 11.20 16.55
19.96 15.44 11.11 11.11
19.65 13.37 11.47 16.43
21.70 15.01 10.92 16.93
20.89 15.42 11.55 17.47
(3.14) (4.57)a (3.27) (3.27)c
(3.19) (3.51) (3.01) (4.71)d
(3.03) (4.88)b (3.66) (3.67)ac
(2.98) (3.55) (3.20) (5.49)ad
(5.80) (4.77) (3.36) (6.03)bc
(6.75) (4.45) (3.29) (6.37)bd
10.80 (4.83)c 12.24 (5.57)c
14.30 (5.93)d 8.68 (3.57)d
10.23 (4.94)c 11.53 (5.29)c
14.15 (6.37)ad 8.57 (3.75)d
10.06 (5.11)c 11.04 (4.97)c
15.27 (6.47)bd 8.31 (3.30)d
5.13 (1.41)
5.02 (1.33)
4.97 (1.47)
4.94 (1.27)
4.95 (1.39)
4.90 (1.35)
5.27 (1.54)
5.60 (1.69)
5.06 (1.56)
5.52 (1.67)
5.12 (1.51)
5.62 (1.77)
4.51 (1.20)
4.43 (0.77)
4.51 (1.30)
4.39 (0.97)
4.49 (1.14)
4.33 (0.94)
4.68 (1.28)
4.93 (1.28)
4.66 (1.33)
4.93 (1.42)
4.60 (1.16)a
5.13 (1.52)b
10.19 (3.34)
11.50 (2.92)
10.05 (3.74)
11.81 (3.15)
10.86 (3.46)
12.25 (2.85)
5.48 (1.71)
4.91 (1.26)
5.14 (1.49)
4.89 (1.29)
5.18 (1.62)
4.93 (1.45)
4.81 (1.37)
4.41 (0.76)
4.73 (1.38)
4.42 (0.94)
4.60 (1.18)
4.54 (1.11)
5.62 (1.92)
5.43 (1.35)
5.32 (1.90)
5.29 (1.38)
5.47 (1.82)
5.35 (1.58)
4.84 (1.52)
4.47 (0.85)
4.71 (1.49)
4.49 (1.12)
4.58 (1.15)
4.59 (1.16)
12.83 (3.81)a
12.79 (3.08)a
11.11 (3.97)b
10.62 (3.30)b
11.63 (3.67)b
10.96 (3.32)b
659
po0:05;
Male mean (Standard deviation)
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BMI Body image importance Body dissatisfaction Extreme weight loss behaviors Strategies to lose weight Strategies to increase muscles Messages from father to lose weight Messages from mother to lose weight Messages from best male friend to lose weight Messages from best female friend to lose weight Messages from media to lose weight Messages from father to increase muscles Messages from mother to increase muscles Messages from best male friend to increase muscles Messages from best female friend to increase muscles Messages from media to increase muscles
Time 2
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In relation to strategies to increase muscles, there were no overall changes over time for the messages from mothers. However, boys were more likely to perceive that mothers were pressing them to increase muscles, F ð2; 539Þ ¼ 6:17, po:01, and there was a significant interaction between gender and time for these messages, F ð2; 539Þ ¼ 5:25, po:01, with messages significantly decreasing over time for boys, but significantly increasing for girls. For fathers, there were no overall changes over time in messages about muscles, but boys were more likely to perceive that their fathers were encouraging to increase muscle, F ð2; 539Þ ¼ 5:54, po:01, and there was a significant interaction between gender and time for these messages, F ð2; 538Þ ¼ 4:80, po:01, with messages significantly decreasing for boys and showing little change for girls. For best male friend, there were no overall changes over time for messages about muscles, no gender differences in the nature of the messages, or significant interaction between time and gender for these messages. There were no overall changes over time in the nature of the messages from best female friend, but boys were more likely to perceive that they were receiving pressure to increase muscles, F ð2; 539Þ ¼ 5:76, po:01, and there was a significant interaction between gender and time for these messages, Fð2; 539Þ ¼ 6:67, po:001, with messages significantly decreasing for boys, but significantly increasing for girls. There were substantial decreases over time in the nature of the messages from the media, F ð2; 539Þ ¼ 72:02, po:001, but there were no perceived gender differences in these messages and no significant gender by time interaction for these messages. 3.3. Prediction of body image and body change strategies A series of hierarchical multiple regression analyses were conducted to determine the contribution of the sociocultural influences to body image and health risk behaviors for boys and girls at time 2 and 3. Analyses were conducted separately for boys and girls. Change scores in the sociocultural variables (i.e. between time 1 and time 2, or between time 1 and time 3) were used to predict change scores in the body image and health risk behaviors over the same period of time. Given the changes that are characteristic of the adolescent period, it was determined that a more meaningful representation of the longitudinal relationships between the variables would be obtained by examining the manner in which changes in the sociocultural variables predicted changes in the body image and body change variables over a shorter period of time (8 months) and a longer period of time (16 months). This method of analysing longitudinal data has been recommended as an appropriate technique by both Rogosa (1995) and Stoolmiller and Bank (1995). The independent variables in each analysis were change scores in messages from: mother, father, best male friend, best female friend, and the media to lose weight; mother, father, best male friend, best female friend, and the media to increase muscles. The dependent variables were change scores in body dissatisfaction, body image importance, strategies to lose weight, extreme weight loss strategies, and strategies to increase muscle. Analyses were conducted for change scores between time 1 and time 2, and between time 1 and time 3. 3.4. Time 1 to time 3 Boys: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 293Þ ¼ 0:89, p4:05; changes in body image importance, F ð10; 293Þ ¼ 0:90, p4:05, and changes in extreme weight loss behaviors, Fð10; 293Þ ¼ 1:08, p4:05. For changes in strategies to
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lose weight, F ð10; 293Þ ¼ 4:45, po0:001, R2 ¼ :13. The variables that provided unique variance to strategies to lose weight were pressures from father to lose weight, pressures from father to increase muscle, and pressures from the media to increase muscle. For changes in strategies to increase muscles, Fð10; 293Þ ¼ 6:18, po0:001, R2 ¼ :17. The variables that provided unique prediction to strategies to increase muscle were changes in pressures from mother to increase muscle, pressures from father to increase muscle, pressures from best male friend to increase muscle, and pressures from the media to increase muscle. See Tables 2–4 for a summary of the beta weights and t values for the regression analyses outlined above. Girls: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 227Þ ¼ 1:23, p4:05, and changes in body image importance, F ð10; 227Þ ¼ 0:92, p4:05. For changes in strategies to lose weight, F ð10; 227Þ ¼ 5:91, po:001, R2 ¼ :21. The variables that provided unique variance were changes in pressures from mother to lose weight, and pressures from father to increase muscle. For changes in extreme weight loss behaviors, F ð10; 227Þ ¼ 2:27, po0:01, R2 ¼ :09. The variables that provided unique prediction were changes in pressure from mother to lose weight, pressures from best male friend to lose weight, and pressures from mother to increase muscle. For changes in strategies to increase muscles, F ð10; 227Þ ¼ 2:64, po0:01, R2 ¼ :10. The variables that provided unique variance were changes in pressures from best female friend to increase muscles, and pressures from the media to increase muscles. See Tables 2–4 for a summary for the beta weights and t values for the regression equations. 3.5. Time 1 to time 3 Boys: Non-significant results were obtained for changes in body dissatisfaction, F(10, 293)=0.40, p>0.05; changes in body image importance, F ð10; 293Þ ¼ 1:03, p4:05; changes in extreme weight loss strategies, F ð10; 293Þ ¼ 1:60, p4:05. For changes in strategies to lose weight Table 2 Summary of beta weights for regression analyses for weight loss Time 1 to time 2 Boys
Lose weight Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
po0:001.
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.08 0.23*** 0.10 0.07 0.03 0.13 0.17* 0.11 0.10 0.21**
1.12 3.56*** 1.52 0.99 0.48 1.82 2.44* 1.75 1.28 2.96**
0.31*** 0.11 0.06 0.11 0.13 0.05 0.15** 0.05 0.01 0.03
4.53*** 1.55 0.87 1.58 1.71 0.83 2.80** 0.72 0.20 0.34
0.08 0.23 0.01 0.04 0.16* 0.08 0.11 0.08 0.01 0.02
1.25 3.58*** 0.14 0.54 2.24* 0.97 1.50 1.25 0.09 0.27
0.21** 0.02 0.05 0.10 0.14 0.09 0.02 0.04 0.03 0.04
2.73** 0.23 0.70 1.38 1.85 1.25 0.23 -0.61 0.45 0.58
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Table 3 Summary of beta weights for regression analyses for extreme weight loss Time 1 to time 2 Boys
Extreme weight loss Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.10 0.05 0.05 0.06 0.14 0.07 0.01 0.02 0.01 0.13
1.30 0.76 0.80 0.78 2.12 0.91 0.09 0.30 0.07 1.70
0.16* 0.01 0.14* 0.05 0.09 0.26*** 0.10 0.02 0.10 0.02
2.19* 0.08 2.04* 0.72 1.12 3.37*** 1.50 0.35 1.40 0.20
0.07 0.10 0.08 0.06 0.07 0.03 0.02 0.11 0.05 0.10
1.06 1.56 1.10 0.80 0.90 0.39 0.23 1.58 0.68 1.41
0.21** 0.01 0.07 0.16* 0.04 0.00 0.04 0.11 0.13* 0.07
2.87** 0.08 0.96 2.31* 0.48 0.00 0.55 1.55 2.35* 0.97
po0:001.
Table 4 Summary of beta weights for regression analyses for strategies to increase muscles Time 1 to time 2 Boys
Increase muscles Mother-lose weight Father-lose weight Male friend-lose weight Female friend-lose weight Media-lose weight Mother-increase muscles Father-increase muscles Male friend-increase muscles Female friend-increase muscles Media-increase muscles
po0:05;
po0:01;
Time 1 to time 3 Girls
Boys
Girls
Beta
t
Beta
t
Beta
t
Beta
t
0.06 0.06 0.00 0.01 0.05 0.16* 0.15* 0.16* 0.06 0.15*
0.88 0.97 0.02 0.15 0.70 2.55* 2.38* 2.58* 0.86 2.18*
0.05 0.04 0.07 0.05 0.03 0.01 0.10 0.07 0.21** 0.19*
0.67 0.57 1.01 0.72 0.33 0.17 1.56 1.00 2.81** 2.29*
0.02 0.04 0.07 0.04 0.11 0.20** 0.15* 0.21** 0.01 0.02
0.23 0.61 1.14 0.56 1.65 2.76** 2.15* 2.87** 0.16 0.23
0.09 0.03 0.08 0.03 0.13 0.19** 0.00 0.09 0.19** 0.03
1.18 0.36 1.16 0.45 1.77 2.78** 0.02 1.25 2.71** 0.44
po0:001.
F ð10; 293Þ ¼ 2:66, po0:01, R2 ¼ :08. The variables that provide unique variance were changes in pressures from father to lose weight, and pressures from the media to lose weight. For changes in strategies to increase muscles, Fð10; 293Þ ¼ 8:01, po0:001, R2 ¼ :22. The variables that provided unique variance were changes in pressures from mother to increase muscle, pressures from father to increase muscle, and pressure from best male friend to increase muscle. See Tables 2–4 for a summary of the beta weight and t values for the regression equations.
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Girls: Non-significant results were obtained for changes in body dissatisfaction, F ð10; 227Þ ¼ 1:41, p4:05, and changes in body image importance, F ð10; 227Þ ¼ 0:76, p4:05. For changes in strategies to lose weight, F ð10; 227Þ ¼ 2:08, po0:05, R2 ¼ :08. The variable that provided unique variance was changes in pressures from mother to lose weight. For changes in extreme weight loss strategies, F ð10; 227Þ ¼ 3:63, po0:001, R2 ¼ :14. The variables that provided unique variance were changes in pressures from mother to lose weight, pressures from best female friend to lose weight, and pressures from best female friend to increase muscles. For changes in strategies to increase muscles, F ð10; 227Þ ¼ 3:26, po:001, R2 ¼ :13. The variables that provided unique variance were changes in pressures from mother to increase muscles, and pressures from best female friend to increase muscles. See Tables 2–4 for a summary of the beta weight and t values for the regression equations.
4. Discussion This longitudinal study was designed to determine changes over time in the body image and health risk behaviors of adolescent boys and girls. Further, it examined the role of sociocultural pressures (i.e., perceived pressures from mother, father, best male friend, best female friend, media) to both lose weight and increase muscle, on the body image and health risk behaviors of both adolescent boys and girls. The results demonstrated that as expected, at all points in time, girls were more likely to adopt strategies to lose weight and extreme weight loss strategies, whereas boys were more likely to adopt strategies to increase muscles. There were also some changes in the body image and body change strategies adopted by boys and girls over this 16 month period. Results of particular clinical concern are the findings that both boys and girls increased their use of extreme body change strategies over time, with girls showing a greater increase than boys. Girls appear to learn at an early age about the sociocultural ideal for girls (Thompson & Heinberg, 1999). As a result, their body image is influenced by this ideal, and they adopt body change strategies that may be injurious to their health to achieve this ideal. As they progress through adolescence, girls may become more aware of this sociocultural ideal and so increase their attempts to achieve it. In contrast, boys showed a reduction in the importance of their body as they progressed through adolescence, and so they were less likely to attempt to lose weight, or increase muscles, and also demonstrated a smaller increase than girls in extreme body change strategies to achieve their ideal body. As boys reach puberty, their bodies are more likely to conform to the sociocultural ideal for boys, and so it may be less necessary for them to engage in these health risk behaviors to achieve this ideal. However, since boys in this study were only, on average, 14.49 years at the completion of the study we are not able to draw conclusions about the focus on muscles among boys later in adolescence. In fact, previous research would suggest that there is an increased focus on muscles among late adolescent boys (see McCabe & Ricciardelli, 2004b, for a review). It is interesting to examine the source of the messages regarding the ideal body for boys and girls. Consistent with previous research (e.g., McCabe et al., 2002; Vincent & McCabe, 2000), the perceived messages to lose weight from peers and the media were higher for girls than boys, whereas the perceived messages from mothers, fathers and female friends to increase muscles were
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higher for boys than for girls. It is important to note that these are perceived messages from the sociocultural forces and the nature of these messages may say more about the body focus of the adolescents, than the actual nature of the messages. The results demonstrated that there were very few changes over time in the nature of the perceived messages from parents, peers or the media to lose weight. However, perceived messages from female friends and the media increased for girls, and perceived messages from the media increased for boys. Thus, friends and the media are clearly targets for prevention programs for adolescent girls, as it would seem that these are the sociocultural influences that are perceived to increase their messages over the adolescent period for girls to lose weight in order to conform to the sociocultural ideal for girls. This change in the level of these perceived messages may be due to the increased focus of girls on achieving this ideal body as they progress through adolescence. Changes over time in the perceived sociocultural messages related to increasing muscles present a different picture. Mothers, fathers, female friends and the media were perceived to decrease their messages regarding muscle size for boys. For girls, mothers and best female friend showed a perceived increase in these messages over time, whereas the media showed a decrease. Despite these changes in messages over time, the sociocultural messages regarding increased muscles were generally higher for boys than for girls. These stronger messages may explain the higher use of strategies to increase muscles among boys, or may be due to boys being more likely to pick up on these messages due to their greater focus on their muscles. These results are somewhat surprising, particularly in relation to girls. They would suggest that girls may be receiving messages that relate to the achievement of a slim toned body, with muscular definition, rather than a slim body alone that has been proposed from previous research (e.g., Byely et al., 2000). A new standard for the ideal body form may be becoming established for adolescent girls. This proposal is certainly consistent with recent research studies (McCabe et al., 2002; Vartanian et al., 2001). Much of the previous research has not investigated the desire for a muscular body in girls, so this has not been highlighted as an area for concern. However, the current findings would suggest that both adolescent boys and girls may be experiencing pressures to increase their muscles. Clearly, further research is needed to determine if girls are now more focused on body tone as well as obtaining a slim body. If this is the case, intervention programs for adolescent boys and girls need to be designed to focus on both strategies to lose weight as well as increasing muscles. The results from the regression analyses demonstrated that changes in sociocultural messages did not predict changes in body image for either boys or girls. These results applied for both the 8 and the 16 month period. These results, combined with the results reported earlier in the discussion, would seem to suggest that body image (both body dissatisfaction and body image importance) is a reasonably stable dimension of the self-image of adolescent boys and girls. It would appear that body image may be part of adolescents’ broader self-image, and not readily changed by messages from sociocultural influences. Fathers were an important influence for boys in terms of both losing weight and increasing muscles. The media also played a strong role in weight loss strategies for boys. It is interesting to note that changes in perceived pressures from both parents and the best male friend predicted changes in strategies to build muscles for boys. These results are consistent with findings from past cross-sectional studies (e.g., Ricciardelli & McCabe, 2003). Both parents and male peers may be particularly focused on sending messages about building muscles to adolescent boys, so that the messages they generate lead adolescent boys to adopt strategies that help them achieve the ideal
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body that is endorsed by society. Messages from female friends did not impact on body image or body change strategies for adolescent boys. During early adolescence (i.e., 13–14 years of age), the opposite sex may not influence the way boys feel about their body, or the strategies they adopt to alter their body. It is important to investigate these same relationships among older adolescent boys, since messages from female friends may have a greater impact during late adolescence. Consistent with the findings for adolescent boys, messages from both parents and peers predicted changes in body change strategies among adolescent girls. Both parents and their best female friends were the most consistent predictor of health risk behaviors. The central role played by messages from parents in shaping a broad range of health risk behaviors among young adolescent girls are demonstrated by these findings: they impacted on losing weight, adopting extreme strategies to lose weight, and even strategies to increase muscles. These results are consistent with previous findings in relation to the role of mothers in shaping strategies to lose weight among adolescent girls (e.g., Benedikt, et al., 1998). They extend these findings to indicate that mothers also play a role in the adoption of strategies to increase muscles among adolescent girls. Consistent with previous studies (e.g., Paxton, Schutz, Wertheim, & Muir, 1999), the results demonstrate the importance of female friends in shaping weight loss, and extreme weight loss strategies. In addition, they indicate that perceived messages from female friends predict strategies to increase muscles. If these results are replicated in other studies, prevention programs for girls may need to be expanded to focus on strategies to increase muscles, as this may be an emerging area of concern among adolescent girls in terms of their health risk behaviors. Messages from opposite-sex peers played a limited role in shaping the body change strategies of both adolescent boys and girls. Early adolescents may not yet have tuned into these messages, and they may be still focused on messages from their parents and same-sex peers. Given the changes that occur in friendship patterns as boys and girls move through adolescence, parents would be expected to play a less central role and opposite-sex peers a more central role as adolescence progresses. A limitation of the current study is that it was reliant upon self-reported questionnaire data. Certainly, research conducted by Stice, Fisher and Lowe (2004) would suggest that despite the correlations between different questionnaire measures of dietary restraint, there is a lack of concordance between self reported dietary restraint and caloric intake. These findings were obtained for female undergraduate students and females frequenting a fast food outlet, and were consistent across the four studies reported in the Stice et al.’s paper. Future studies need to also utilize interview techniques to obtain a better understanding, not only on the nature of the relationship between sociocultural influences and health risk behaviors, but also of the meaning placed on the messages from the sociocultural agents. In this way, it will be possible to better understand the cognitive interpretation placed on these perceived messages. It is also important to determine the actual nature of the messages generated by the sociocultural agents. This will identify any interpretative bias, which may be occurring among adolescents. These data are important to inform any prevention or intervention program to modify cognitions that are focused on achieving an unrealistic body shape, so as to prevent high levels of body dissatisfaction and the adoption of health risk behaviors. The results of this study demonstrate that perceived messages from mothers, fathers and samesex peers play an important role in shaping strategies to both lose weight and increase muscle tone among adolescent boys and girls. Further studies need to explore the relationship between the
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actual and perceived messages from the various sources. Although boys are more focused on increasing muscles, and girls are more focused on losing weight, the results in this study suggest that both boys and girls are striving to achieve a slim, toned body. Rather than the ideal body for the different sexes being radically different from one another, the difference may only be one of degree. These findings have implications for the types of prevention and intervention programs developed to address disordered eating and extreme strategies to increase muscles for adolescents. These programs need to address the full range of health risk behaviors that are adopted to achieve the ideal body endorsed by the sociocultural influences investigated in this study.
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