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Determinants of Eating Attitudes among Overweight and Nonoverweight Adolescents
Journal of Adolescent Health 41 (2007) 138 –145
Original article
Determinants of Eating Attitudes among Overweight and Nonoverweight Adolescents Danielle Symons Downs, Ph.D.a,*, Jennifer M. DiNallo, M.A.a, Jennifer S. Savage, M.S.b, and Kirsten Krahnstoever Davison, Ph.D.c a
Exercise Psychology Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania b Department of Nutritional Sciences, The Pennsylvania State University, University Park, Pennsylvania c State University of New York at Albany, Albany, New York Manuscript received October 25, 2006; manuscript accepted March 23, 2007
Abstract
Purpose: Limited research has examined the determinants of eating attitudes among both adolescent boys and girls. The aims of this study were to examine the extent to which depressive symptoms, body satisfaction, and physical activity (PA) predict eating attitudes in adolescent boys and girls, and to determine the moderating influences of sex and body mass index (BMI). Methods: The participants (N ⫽ 646 adolescent boys and girls; mean age 14.28 years; 49% boys) completed self-reported measures of their depressive symptoms, body satisfaction, leisure-time PA, and eating attitudes during their high school health and physical education classes. Results: Hierarchical regression analyses revealed that: (1) BMI, depressive symptoms, body satisfaction, PA, and their interaction terms explained 14% and 17% of the variance in eating attitudes for boys and girls, respectively; (2) BMI moderated the contributions of body satisfaction and PA for predicting eating attitudes such that overweight boys scored lower on body satisfaction and higher on PA than normal-weight boys; and (3) BMI did not moderate the contributions of any of the psychobehavioral constructs for predicting eating attitudes among girls. Conclusions: Our findings illustrate that eating attitudes are determined differently for boys and girls, and the findings demonstrate the need for sex-specific interventions to promote healthy eating attitudes and behaviors during adolescence. © 2007 Society for Adolescent Medicine. All rights reserved.
Keywords:
Body satisfaction; Depression; Physical activity; Sex differences; Eating; Weight; Obesity
Disordered eating attitudes and behaviors, as well as overweight during adolescence, are major public health issues with physical and psychological consequences [1,2]. Although 1– 4% of adolescents have disordered eating behaviors, nearly 27% of girls aged 12–18 years report negative eating attitudes. Moreover, the prevalence of overweight among children and adolescents has doubled over the past three decades [2,3]. Although negative eating attitudes may not always manifest as disordered eating behaviors, they are arguably important psychological risk factors worthy of attention among youth. How*Address correspondence to: Dr. Danielle Symons Downs, 266 Recreation Building, Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802. E-mail address: [email protected]
ever, the direction of causality between weight status and negative eating attitudes is unclear. There is some evidence to support the associations between negative eating attitudes and depression and body dissatisfaction among youth. However, research studying the behavioral influences of physical activity (PA) on eating attitudes is equivocal. That is, increased PA has been linked with both healthy and unhealthy eating attitudes and behaviors during adolescence. Also, the links between eating attitudes and depression, body satisfaction, and PA have been studied primarily in girls. Thus, research collectively examining these psychobehavioral determinants of eating attitudes is warranted to inform the prevention of eating pathology among adolescent boys and girls. Although depression and body dissatisfaction are common psychological problems increasing the risk of disor-
1054-139X/07/$ – see front matter © 2007 Society for Adolescent Medicine. All rights reserved. doi:10.1016/j.jadohealth.2007.03.007
D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
dered eating behaviors [4,5], the association between PA and eating attitudes is less understood. One located longitudinal study examined the influence of depression on eating attitudes in youth and found that depression was the strongest predictor of eating attitudes [6]. Furthermore, normative stressors during developmental transitions (i.e., adolescence) may put girls at risk for eating problems [7]. An increased emphasis on maintaining a thin or ideal body may also place adolescents at risk for body dissatisfaction [8], which is a strong predictor of eating attitudes [9]. However, few studies have examined depression and body satisfaction as determinants of eating attitudes among both boys and girls [10,11]. Although the influence of PA on decreasing depressive symptoms [12] and improving body satisfaction [13] among adolescents is well-evidenced, no located studies have examined the contribution of PA as a determinant of eating attitudes in nonclinical adolescent populations. It is well evidenced that psychobehavioral predictors of eating attitudes are influenced by weight status, such that overweight boys and girls are more likely to report body dissatisfaction and depressive symptoms than their normal-weight counterparts [14]. In addition, there is evidence that weight status is also associated with PA, such that overweight adolescents may engage in fewer minutes of vigorous PA than their normal-weight peers [15]. However, to date, no located study has examined the collective influences of depressive symptoms, body satisfaction, and PA behavior for predicting eating attitudes among adolescent boys and girls. Thus it is important to examine sex and weight status group differences among these determinants of eating attitudes so as to develop targeted prevention programs for successful improvement of adolescent physical and psychological well-being. The purpose of this study was to examine the extent to which depressive symptoms, body satisfaction, and PA predict eating attitudes in adolescent boys and girls, and to determine the moderating influences of sex and weight status. Based on previous research [4,5,10,11,14,16,17], we hypothesized that: (1) more depressive symptoms, lower body satisfaction, and lower levels of PA behavior would be associated with higher negative eating attitude scores; (2) boys would score higher on body satisfaction and PA and lower on negative eating attitudes than girls; (3) normal-weight adolescents would score higher on body satisfaction and PA and lower on negative eating attitudes than overweight adolescents; and (4) higher levels of PA would predict lower negative eating attitude scores after controlling for the contributions of body satisfaction and depressive symptoms. Methods Participants Participants were 646 high school boys and girls (mean age 14.28 years, SD ⫽ 0.66 years; 49% boys). Participants
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were in the 8th (52.5%) and 9th (47.5%) grades. Participants were Caucasian (85.1%), followed by Asian American (5.7%), African American (3.8%), Hispanic American (2.6%), and other (2.8%). Measures The Personal History Questionnaire assessed the participants’ sex, age, grade in school, race/ethnicity, and selfreported height and weight. Body mass index (BMI) was calculated by converting self-reported weight from pounds to kilograms, and by transforming self-reported height from inches to meters (kg/m2). Self-reported BMI has been found to be highly correlated with actual BMI in adolescents [18]. Participants were grouped into categories (i.e., normal and overweight/obese) based on BMI-for-age percentage cutoff points established by the Centers for Disease Control and Prevention [19]. The Center for Epidemiological Studies Depression Scale (CES-D) [20] is a 20-item self-report measure of the degree of depressive symptoms experienced in the past week. Participants rate their responses using a five-point Likert scale and scores are recoded ranging from 0 to 3, with a higher score indicative of more severe depressive symptoms. The internal consistency score in the current study was acceptable (␣ ⫽ 0.78). The Body Areas Satisfaction Scale (BASS) is a 9-item subscale of the Multidimensional Body Self-Relations Questionnaire [21]. Participants rate the degree of satisfaction with specified body parts (e.g., face, thighs) and overall muscle tone, weight, height, and appearance using a fivepoint Likert scale ranging from 1 to 5. A higher score on the BASS represents greater satisfaction with one’s body. The internal consistency of the total BASS score in this study was good (␣ ⫽ .85). The Leisure-Time Exercise Questionnaire (LTEQ) [22] assesses self-reported mild, moderate, and strenuous leisure-time PA that is done for at least 15 minutes during a typical week. Consistent with previous researchers [23] and current exercise recommendations [24] we rephrased the instrument to assess leisure-time PA that is done for at least 30 minutes. A weekly PA index in metabolic equivalents (METs) is generated with the following formula: (5 ⫻ moderate bouts) ⫹ (9 ⫻ strenuous bouts). The LTEQ has been used previously to assess adolescent PA [25], and the test–retest value of the LTEQ with adolescents was reported to be .84 [26]. The Children’s Eating Attitudes Test (chEAT) [23] is a 26-item self-report measure of maladaptive or problematic eating attitudes in children. Participants rate their responses using a six-point Likert scale ranging from 1 to 6. A higher score is representative of more problematic or maladaptive eating attitudes and a cutoff of 20 is indicative of risk for eating disorder pathology (i.e., higher scores mean higher levels of negative eating attitudes). In the current study, the
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internal consistency of the total chEAT score was excellent (␣ ⫽ .90). Design and procedure The University’s Institutional Review Board and the School District’s Board of Education approved this study, and informed consent was obtained in accordance with university guidelines (i.e., the students and their parents completed written informed consent forms). The response rate was 51.2% (681/1,329), which is similar to other studies examining health behaviors in adolescents [27]. Thirty participants did not report their weight to calculate BMI, and five students with incomplete data were eliminated from the analyses; thus the final sample size was 646. Data analyses Descriptive characteristics are given in Table 1. To examine weight status, participants were classified according to the guidelines published by the Centers for Disease Control and Prevention [19]. These guidelines suggest that a BMI percentile ⱖ85 and ⬍95 is classified as at risk of overweight and a BMI ⱖ95 is classified as overweight; however, the participants in this study who were at risk of overweight and who were overweight were examined as a single group. Also we excluded the participants in the underweight category (n ⫽ 8) from further analyses because of the small sample size. Therefore, to simplify the presentation and discussion of results, participants were classified as either normal weight (⬎5th and ⬍85th percentile; n ⫽ 455) or overweight (ⱖ85th percentile; n ⫽ 183). Pearson correlations were used to examine the associations among the study variables for the total sample and by sex and BMI status. To examine group differences on the study variables the nonparametric Kruskal-Wallis (K-W), Table 1 Characteristics of the study sample (N ⫽ 646) N Body mass index Normal weight Overweight Height (in) Weight (lb) Age Sex Female Male Race/ethnicity Caucasian/white Asian African American Hispanic/Latino Other Grade 8th grade 9th grade
646 455 183 646 646 675
% 71.0 29.0
Mean
Range
SD
21.96 20.01 27.10 64.63 130.8 14.28
(15–47) (15–26) (22–47) (55–74) (62–256) (13–16)
4.21 1.88 4.02 3.26 29.34 0.66
319 327
49.4 50.6
— —
— —
— —
571 32 14 9 49
84.6 4.7 2.1 1.3 7.3
— — — — —
— — — — —
— — — — —
330 316
51.1 48.9
— —
— —
— —
one-way ANOVA by ranks was used because the comparison groups were unequal (i.e., normal-weight group was larger than the overweight group); thus, the assumption of traditional parametric ANOVA was violated [28,22]. All statistical tests were conducted with alpha set at .05. To examine the contributions of depressive symptoms, body satisfaction, and PA for predicting negative eating attitudes, two hierarchical regression analyses by sex were conducted. The order and content of the blocks of variables were based on previous research [29] and regression analyses including sex interaction terms [30,31]. Eating attitudes (DV) was regressed on BMI (Block 1), depressive symptoms and body satisfaction (Block 2), PA (Block 3), and the interaction terms for BMI (e.g., PA*BMIgroup) in Block 4. Based on regression models with multiple predictor variables, and a priori power of .80 and alpha of .05, adequate power was obtained to conduct these analyses [32]. The tolerance values for the two regression analyses revealed that we had multicollinearity among our independent variables (values ⬎ .20). Thus, to reduce multicollinearity, we centered the variables (i.e., subtracting the mean for each predictor variable), which resolved this issue [33]. Results Correlations for study variables by sex and BMI status Pearson correlations among the psychosocial and behavioral variables for the total sample and across sex and BMI are presented in Table 2. High levels of depressive symptoms were associated with negative eating attitudes for normal-weight boys and both normal and overweight girls. Also, the normal-weight and overweight girls reporting low levels of body satisfaction also reported high levels of negative eating attitudes; however, this association was not significant for boys. Finally, normal-weight girls scoring high on PA also reported high levels of negative eating attitudes. However, this association was not significant for boys or overweight girls. BMI and sex differences across the study variables When participants were grouped by BMI, significant group differences were found for body satisfaction for boys [k-w (1) ⫽ 8.42, p ⬍ .001, 2⫽ .03] and girls [k-w (1) ⫽ 22.49, p ⬍ .001, 2⫽ .07] (Table 3), such that normalweight boys and girls scored significantly higher on body satisfaction than overweight boys and girls. No group differences were observed for depressive symptoms or eating attitudes for boys or girls; however, significant group differences were noted for PA among girls [k-w (1) ⫽ 3.71, p ⬍ .05, 2⫽ .01] such that normal-weight girls reported significantly more PA behavior than overweight girls. No BMI group differences were found for boys (p ⬎ .05).
D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
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Table 2 Correlations for the study variables by sex and body mass index (BMI) status Depression
Eating attitudes Total Normal weight Overweight Depression Total Normal weight Overweight Body satisfaction Total Normal weight Overweight a b
Body satisfaction
Physical activity
Total
Boys
Girls
Total
Boys
Girls
Total
Boys
.23a .23a .21b
.21a .27a .14
.26a .21a .31a
⫺.23a ⫺.21a ⫺.32a
⫺.04 ⫺.02 ⫺.19
⫺.30a ⫺.30a ⫺.35a
.08 .08 .08
.08 .08 .18
— — —
— — —
— — —
⫺.12a ⫺.12b ⫺.16b
⫺.09 ⫺.10 ⫺.09
⫺.17a ⫺.16b ⫺.31a
⫺.08b ⫺.08 ⫺.15
⫺.14b ⫺.15b ⫺.17
— — —
— — —
— — —
.29a .23a .40a
.37a .38a .39a
Girls .16a .17b .10 ⫺.03 ⫺.03 ⫺.16 .14b .03 .26b
p ⬍ .01 (two-tailed). p ⬍ .05 (two-tailed).
Predicting eating attitudes by sex Predicting eating attitudes for boys. In the first block of the model, BMI group explained 1% of the variance in eating attitudes (Table 4). When depressive symptoms and body satisfaction were included in the second block, an additional 7% of the variance was explained with depressive symptoms emerging as the only significant predictor. When PA was included in the third block, an additional 2% of the variance was explained, with PA and depression predicting eating attitudes and PA emerging as the strongest determinant. Finally, an additional 4% of the variance was explained when the interaction terms were included in the fourth block. Specifically, the interaction terms PA group*BMI classification and body satisfaction group*BMI classification significantly predicted eating attitudes. The main effects for BMI group, depression, and body satisfaction maintained their significant contribution; however the
interaction term for body satisfaction group*BMI classification emerged as the strongest determinant. To further examine the interactions for body satisfaction and PA, mean tertile splits were conducted. We examined the high PA score for normal-weight group (mean [M] ⫽ 79.92, SD ⫽ 13.51) and overweight group (M ⫽ 84.25, SD ⫽ 13.04); and low PA score for normal-weight group (M ⫽ 18.68, SD ⫽ 11.21) and overweight group (M ⫽ 11.68, SD ⫽ 8.79). Similarly, we examined the high body satisfaction score for normal-weight group (M ⫽ 35.46, SD ⫽ 2.77) and overweight group (M ⫽ 35.33, SD ⫽ 3.04); and low body satisfaction score for normal-weight group (M ⫽ 23.02, SD ⫽ 2.72) and overweight group (M ⫽ 22.08, SD ⫽ 3.31). Figure 1 illustrates that overweight boys in the high PA group reported more negative eating attitudes compared with normal-weight boys in the high PA group. Figure 2 illustrates that normal-weight boys in the low body satisfaction group reported more negative
Table 3 Mean and standard deviation (SD) scores for the study variables for all participants, by sex and body mass index group
All participants Total Normal weight Overweight Boys Total Normal weight Overweight Girls Total Normal weight Overweight
Depressive symptoms Mean (SD)
Body satisfaction Mean (SD)
Physical activity Mean (SD)
Eating attitudes Mean (SD)
6.29 (2.92) 6.24 (2.91) 6.26 (2.88)
27.77 (6.18) 28.45 (6.03)a 25.95 (6.09)b
43.56 (28.29) 44.29 (27.47) 41.14 (29.55)
5.33 (5.73) 5.29 (5.83) 5.84 (5.69)
6.37 (3.05) 6.31 (3.0) 6.31 (3.01)
29.35 (5.93) 30.06 (5.72)a 27.88 (6.12)b
49.97 (29.15) 50.69 (28.45) 49.02 (31.41)
4.31 (4.50) 4.28 (4.40) 4.79 (5.11)
6.21 (2.79) 6.19 (2.83) 6.19 (2.74)
26.23 (3.04) 27.09 (5.96)a 23.64 (5.22)b
37.52 (26.10) 38.86 (25.44)a 32.60 (24.88)b
6.35 (6.59) 6.21 (6.75) 6.99 (6.11)
Superscript letters indicate significant group differences (p ⬍ .05).
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D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145 Table 4 Hierarchical regression analyses predicting eating attitudes for boys and girls Variable Predicting eating attitudes for boys Block 1 BMI group Block 2 Depression Body satisfaction Block 3 PA Block 4 Depression*BMI group Body satisfaction*BMI group PA*BMI group Predicting eating attitudes for girls Block 1 BMI group Block 2 Depression Body satisfaction Block 3 PA Block 4 Depression*BMI group Body satisfaction*BMI group PA*BMI group
df
R2 change
.68
1,230
.01
8.01b
2,228
.07
F change
1
.05
2
.04
3
.04
.25b .26b ⫺.01 ⫺.08 5.05c
1,227
3.81
3,224
1.01a .38c .57a
.02 .56c
a
4
⫺.26
.04 ⫺.16 ⫺1.26a .51c
.71
1,245
.01
2,243
.12
.05 16.83b
10.33b .18
1,242
.04
3,239
.01
⫺.01
.004
.11
.18a .19a ⫺.27b ⫺.29b
.15 ⫺.22
.19a
.27 .05 ⫺.11 ⫺.09
Abbreviations. BMI ⫽ body mass index; PA ⫽ physical activity. 1-4 ⫽ standardized regression coefficients for Equations 1, 2, 3, and 4; df ⫽ degrees of freedom. a p ⬍ .01. b p ⬍ .001. c p ⬍ .05.
eating attitudes compared with overweight boys in the low body satisfaction group. Predicting eating attitudes for girls. In the first block of the model, BMI explained 1% of the variance in eating attitudes. When depressive symptoms and body satisfaction were entered in the second block, an additional 12% of the variance was explained. Both depressive symptoms and body satisfaction were significant determinants; however body satisfaction emerged as the strongest predictor. When
PA was entered in the third block, an additional 4% of the variance was explained, with depressive symptoms maintaining its significant contribution and body satisfaction emerging as the strongest determinant. Finally, an additional 1% of the variance was explained when the interaction terms, PA*BMIgroup, body satisfaction*BMIgroup, and Depression*BMIgroup, were included in the fourth block; however none of the main effects or interaction terms emerged as significant determinants.
Figure 1. Illustration of physical activity group*BMI classification for predicting boys’ scores on the Children’s Eating Attitudes Test (chEAT).
Figure 2. Illustration of the interaction of body satisfaction*BMI classification for predicting boys’ scores on the Children’s Eating Attitudes Test (chEAT).
D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
Discussion The purpose of our study was to examine the collective influences of depressive symptoms, body satisfaction, and PA for determining the eating attitudes of adolescent boys and girls, and to examine the moderating influences of sex and weight status. In general the study findings illustrate that, among boys, weight status moderated the predictive contributions of body satisfaction and PA on eating attitudes. Specifically, overweight boys scored lower on body satisfaction and higher on PA compared with normal-weight boys. However this moderating influence was not observed for depressive symptoms among boys. Among girls the weight status did not moderate the existing associations among any of the psychobehavioral correlates for predicting eating attitudes; however, all three main effects significantly predicted eating attitudes. Several findings warrant further discussion. In support of our first hypothesis and previous research [4,9,10], depressive symptoms and body satisfaction were significantly associated with eating attitudes for girls, with body satisfaction emerging as the strongest correlate. Our findings are consistent with previous research [1]. For example, Johnson and Wardle [9] examined the longitudinal associations between eating attitudes and body satisfaction in a school-based sample of adolescent girls (ages 13–15 years), and found that body dissatisfaction was the strongest independent factor predicting eating attitudes. Thus identifying factors facilitating positive and negative body satisfaction is an important aspect of understanding negative eating attitudes among girls. Among boys, only depressive symptoms was associated with eating attitudes, suggesting that normal-weight boys reporting high depressive symptoms also reported more problematic eating attitudes. This finding is also consistent with previous research [31]. Therefore it is important to recognize that boys who report depressive symptoms may also be at risk for eating disorders. Because of the cross-sectional nature of this study, this relationship can also be interpreted that boys who report problematic eating attitudes may be at risk for depressive symptoms. As predicted in our second hypothesis, and consistent with previous research [8,11,19], boys scored higher on measures of PA and body satisfaction, and lower on negative eating attitudes compared with girls. This sex difference is not surprising, considering the increased emphasis on maintaining a thin or ideal body that increases girls’ risk for body dissatisfaction and pathologic eating behavior. However, it is important to note that the prevalence of body dissatisfaction and eating disorders may be increasing in boys [34], as they may desire a more muscular figure. Because of sex differences in body satisfaction, current measures are limited in that they only assess dissatisfaction with adiposity and fail to measure dissatisfaction with muscularity. Thus additional research
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on boys is warranted to confirm our study findings and to enable one to draw more conclusive evidence concerning the sex differences among adolescent boys and girls. In support of our third hypothesis and previous research [14], significant group differences were observed for body satisfaction for normal and overweight adolescents. Adolescence is a time of constant change, with intense pressure to belong. For example, young overweight adolescents have reported having fewer friends, being less liked by parents, being less happy, and being less attractive than their normalweight counterparts [35]. Along with these self-evaluative concerns during adolescence, there are increasing rates of obesity and eating disorders [36]. However, in contrast to our third hypothesis, there were no significant group differences observed for eating attitudes between normal and overweight adolescents. Collectively, these findings suggest that just being overweight during adolescence may not increase the risk for depressive symptoms or negative eating attitudes; however body satisfaction does appear to be influenced by weight status. That is, our findings demonstrated that compared with normal-weight adolescents, overweight adolescents exhibited lower body satisfaction, which may be the important psychological factor to target for intervention. For PA, group differences were observed with boys scoring higher than girls and normal-weight girls scoring higher than overweight girls. Consistent with the findings of Patrick et al [15], normal-weight girls reported more minutes engaged in PA compared with overweight girls. Existing literature has linked weight-based teasing to body dissatisfaction among overweight youth [37], which may pose a barrier to involvement in PA. In addition, compared with their normal-weight peers, overweight girls may have been less comfortable (i.e., physically, emotionally) participating in PA [38]. Although both overweight and normal-weight girls may have a desire to improve body satisfaction and to achieve ideal body, normal-weight girls may perceive fewer barriers to being physically activity than overweight girls (i.e., embarrassment, discomfort). It is important to note that dieting behavior was not assessed in this study; and this may confound these findings if PA was used as a means of dieting. Also, because the LTEQ assesses leisure activities by time spent in PA and intensity level, we do not have data on the specific types of activities for which adolescents reported time and intensity. Thus girls may not recognize that some of the activities they engage in are actually forms of PA (i.e., house chores), and therefore, may have underestimated the amount of time they spent in PA. In contrast to our fourth hypothesis, PA did not emerge as the strongest predictor of eating attitudes in adolescent boys and girls. Before the addition of the interaction terms, PA was a significant predictor of eating attitudes. However, this association depended on weight status such that overweight boys in the high PA group reported more negative
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eating attitudes than normal-weight boys, although overweight boys in the low PA group reported less negative eating attitudes than normal-weight boys. A similar interaction was observed for body satisfaction group and BMI classification for predicting eating attitudes. One potential explanation for these associations is that boys may have both a thin and larger body ideal in that they were striving to achieve a lean and muscular body through variations of PA and diet to meet societal ideals [8]. Alternatively, it is plausible that boys may have engaged in more resistancetype activities (e.g., weight training) and were not finished growing, and therefore had higher BMIs. Consistent with previous research [16], the main effect for depressive symptoms maintained its contribution, but there was no interaction with weight status for either boys or girls. Also, regardless of weight status, girls’ body satisfaction and PA equally predicted eating attitudes. Thus, to improve eating attitudes among adolescent girls, a universal intervention focused on increasing body satisfaction and PA behavior may be effective. However our findings suggest that factors predicting eating attitudes may vary among boys and girls; therefore interventions designed to prevent negative eating attitudes should be sex-specific. Although our findings contribute to the adolescent eating attitudes literature by including leisure-time PA in combination with depressive symptoms and body satisfaction, as well as studying the moderating influences of sex and BMI, there were study limitations. First, because of the crosssectional nature of the study, no causal inferences can be made about the influences of depressive symptoms, body satisfaction, and PA in predicting eating attitudes. Second, although PA was assessed with a valid and reliable measure, it was nonetheless obtained through self-report, which is inherently biased by social desirability. Third, only 3% of adolescents in this study scored above 20 (i.e., the clinical cut-off for eating attitude scores on the chEAT); thus, these findings may not be easily generalized to adolescent populations with a greater prevalence of clinically significant negative eating attitudes. Finally the study findings can only be generalized to white, middle-to-high income adolescent populations. In conclusion, sex and weight status differences appear to exist for the risk of negative eating attitudes during adolescence. Our study findings illustrate that eating attitudes are determined differently for boys and girls, and they demonstrate the need for sex-specific interventions to promote healthy eating attitudes during adolescence. Although most of the research on eating attitudes has been focused on girls, the present study suggests that adolescent boys and girls are at similar risk for negative eating attitudes. Future research is warranted to understand how dieting, the thin ideal, and various types of PA may affect these associations in adolescent boys and girls [39].
Acknowledgments We acknowledge Dr. George Graham, Dr. Sandy Bargainnier, Stephen Yang, Jay Vasil, Margie Swoboda, and the students, parents, administrators, teachers, and staff from State College Area School District in State College, Pennsylvania, for their assistance with this study. References [1] Stice E, Whitenton K. Risk factors for body dissatisfaction in adolescent girls: a longitudinal investigation. Dev Psychol 2002;38:669 –78. [2] Hedley AA, Ogden CL, Johnson CL, et al. Prevalence of overweight and obesity among US children, adolescents, and adults, 1999 –2002. JAMA 2004;291:2847–50. [3] American Psychological Association, 2000, available at: http://www. apahelpcenter.org/articles/topic.php?id⫽6#Eating%20Disorders, American Psychological Association, 2000. Accessed November 14, 2006. [4] Fulkerson JA, Sherwood NE, Perry CL, et al. Depressive symptoms and adolescent eating and health behaviors: a multifaceted view in a population-based sample. Prev Med 2004;38:865–75. [5] Leon GR, Fulkerson JA, Perry CL, et al. Personality and behavioral vulnerabilities associated with risk status for eating disorders in adolescent girls. J Abnorm Psychol 1993;102:438 – 44. [6] Garner D, Garfinkel P. The eating attitudes test: an index of the symptoms of anorexia nervosa. Psychol Med 1979;9:273–9. [7] Smolak L, Levine M, Striegel-Moore R. The Developmental Psychopathology of Eating Disorders: Implications for Research, Prevention, and Treatment. Mahwah, NJ: Lawrence Erlbaum Associates, 1996, [8] Furnham A, Badmin N, Sneade I. Body image dissatisfaction: sex differences in eating attitudes, self-esteem, and reasons for exercise. J Psychol 2002;136:581–96. [9] Johnson F, Wardle J. Dietary restraint, body dissatisfaction, and psychological distress: a prospective analysis. J Abnorm Psychol 2005;114:119 –25. [10] Kovacs M, Obrosky DS, Sherrill J. Developmental changes in the phenomenology of depression in girls compared with boys from childhood onward. J Affect Disord 2003;74:33– 48. [11] Hausenblas H, Symons Downs D. Body image in middle school children. Eating Weight Disord 2002;7:244 – 8. [12] Motl R, Birnbaum A, Kubik M, et al. Naturally-occurring changes in physical activity are inversely related to depressive symptoms during early adolescence. Psychosom Med 2004;66:336 – 42. [13] Neumark-Sztainer D, Paxton SJ, Hannan PJ, et al. Does body satisfaction matter? Five-year longitudinal associations between body satisfaction and health behaviors in adolescent females and males. J Adolesc Health 2006;39:244 –51. [14] Crow S, Eisenberg ME, Story M, et al. Psychosocial and behavioral correlates of dieting among overweight and non-overweight adolescents. J Adolesc Health 2006;38:569 –74. [15] Patrick KK, Norman GJ, Calfas KJ, et al. Diet, physical activity, and sedentary behaviors as risk factors for overweight in adolescence. Arch Pediatr Adolesc Med 2004;158:385–90. [16] Garner D, Garfinkel P. The eating attitides test: an index of the symptoms of anorexia nervosa. Psychol Med 1979;9:273–9. [17] DeBate R, Thompson S. Girls on the Run: improvements in selfesteem, body size satisfaction and eating attitudes/behaviors. Eat Weight Disord 2005;10:25–32. [18] Himes JH, Hannan P, Wall M, et al. Factors associated with errors in self-reports of stature, weight, and body mass index in Minnesota adolescents. Ann Epidemiol 2005;15:272– 8. [19] Centers for Disease Control and Prevention, Prevalence of overweight among children and adolescents: United States, 1999 Avail-
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Original article
Determinants of Eating Attitudes among Overweight and Nonoverweight Adolescents Danielle Symons Downs, Ph.D.a,*, Jennifer M. DiNallo, M.A.a, Jennifer S. Savage, M.S.b, and Kirsten Krahnstoever Davison, Ph.D.c a
Exercise Psychology Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania b Department of Nutritional Sciences, The Pennsylvania State University, University Park, Pennsylvania c State University of New York at Albany, Albany, New York Manuscript received October 25, 2006; manuscript accepted March 23, 2007
Abstract
Purpose: Limited research has examined the determinants of eating attitudes among both adolescent boys and girls. The aims of this study were to examine the extent to which depressive symptoms, body satisfaction, and physical activity (PA) predict eating attitudes in adolescent boys and girls, and to determine the moderating influences of sex and body mass index (BMI). Methods: The participants (N ⫽ 646 adolescent boys and girls; mean age 14.28 years; 49% boys) completed self-reported measures of their depressive symptoms, body satisfaction, leisure-time PA, and eating attitudes during their high school health and physical education classes. Results: Hierarchical regression analyses revealed that: (1) BMI, depressive symptoms, body satisfaction, PA, and their interaction terms explained 14% and 17% of the variance in eating attitudes for boys and girls, respectively; (2) BMI moderated the contributions of body satisfaction and PA for predicting eating attitudes such that overweight boys scored lower on body satisfaction and higher on PA than normal-weight boys; and (3) BMI did not moderate the contributions of any of the psychobehavioral constructs for predicting eating attitudes among girls. Conclusions: Our findings illustrate that eating attitudes are determined differently for boys and girls, and the findings demonstrate the need for sex-specific interventions to promote healthy eating attitudes and behaviors during adolescence. © 2007 Society for Adolescent Medicine. All rights reserved.
Keywords:
Body satisfaction; Depression; Physical activity; Sex differences; Eating; Weight; Obesity
Disordered eating attitudes and behaviors, as well as overweight during adolescence, are major public health issues with physical and psychological consequences [1,2]. Although 1– 4% of adolescents have disordered eating behaviors, nearly 27% of girls aged 12–18 years report negative eating attitudes. Moreover, the prevalence of overweight among children and adolescents has doubled over the past three decades [2,3]. Although negative eating attitudes may not always manifest as disordered eating behaviors, they are arguably important psychological risk factors worthy of attention among youth. How*Address correspondence to: Dr. Danielle Symons Downs, 266 Recreation Building, Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802. E-mail address: [email protected]
ever, the direction of causality between weight status and negative eating attitudes is unclear. There is some evidence to support the associations between negative eating attitudes and depression and body dissatisfaction among youth. However, research studying the behavioral influences of physical activity (PA) on eating attitudes is equivocal. That is, increased PA has been linked with both healthy and unhealthy eating attitudes and behaviors during adolescence. Also, the links between eating attitudes and depression, body satisfaction, and PA have been studied primarily in girls. Thus, research collectively examining these psychobehavioral determinants of eating attitudes is warranted to inform the prevention of eating pathology among adolescent boys and girls. Although depression and body dissatisfaction are common psychological problems increasing the risk of disor-
1054-139X/07/$ – see front matter © 2007 Society for Adolescent Medicine. All rights reserved. doi:10.1016/j.jadohealth.2007.03.007
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dered eating behaviors [4,5], the association between PA and eating attitudes is less understood. One located longitudinal study examined the influence of depression on eating attitudes in youth and found that depression was the strongest predictor of eating attitudes [6]. Furthermore, normative stressors during developmental transitions (i.e., adolescence) may put girls at risk for eating problems [7]. An increased emphasis on maintaining a thin or ideal body may also place adolescents at risk for body dissatisfaction [8], which is a strong predictor of eating attitudes [9]. However, few studies have examined depression and body satisfaction as determinants of eating attitudes among both boys and girls [10,11]. Although the influence of PA on decreasing depressive symptoms [12] and improving body satisfaction [13] among adolescents is well-evidenced, no located studies have examined the contribution of PA as a determinant of eating attitudes in nonclinical adolescent populations. It is well evidenced that psychobehavioral predictors of eating attitudes are influenced by weight status, such that overweight boys and girls are more likely to report body dissatisfaction and depressive symptoms than their normal-weight counterparts [14]. In addition, there is evidence that weight status is also associated with PA, such that overweight adolescents may engage in fewer minutes of vigorous PA than their normal-weight peers [15]. However, to date, no located study has examined the collective influences of depressive symptoms, body satisfaction, and PA behavior for predicting eating attitudes among adolescent boys and girls. Thus it is important to examine sex and weight status group differences among these determinants of eating attitudes so as to develop targeted prevention programs for successful improvement of adolescent physical and psychological well-being. The purpose of this study was to examine the extent to which depressive symptoms, body satisfaction, and PA predict eating attitudes in adolescent boys and girls, and to determine the moderating influences of sex and weight status. Based on previous research [4,5,10,11,14,16,17], we hypothesized that: (1) more depressive symptoms, lower body satisfaction, and lower levels of PA behavior would be associated with higher negative eating attitude scores; (2) boys would score higher on body satisfaction and PA and lower on negative eating attitudes than girls; (3) normal-weight adolescents would score higher on body satisfaction and PA and lower on negative eating attitudes than overweight adolescents; and (4) higher levels of PA would predict lower negative eating attitude scores after controlling for the contributions of body satisfaction and depressive symptoms. Methods Participants Participants were 646 high school boys and girls (mean age 14.28 years, SD ⫽ 0.66 years; 49% boys). Participants
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were in the 8th (52.5%) and 9th (47.5%) grades. Participants were Caucasian (85.1%), followed by Asian American (5.7%), African American (3.8%), Hispanic American (2.6%), and other (2.8%). Measures The Personal History Questionnaire assessed the participants’ sex, age, grade in school, race/ethnicity, and selfreported height and weight. Body mass index (BMI) was calculated by converting self-reported weight from pounds to kilograms, and by transforming self-reported height from inches to meters (kg/m2). Self-reported BMI has been found to be highly correlated with actual BMI in adolescents [18]. Participants were grouped into categories (i.e., normal and overweight/obese) based on BMI-for-age percentage cutoff points established by the Centers for Disease Control and Prevention [19]. The Center for Epidemiological Studies Depression Scale (CES-D) [20] is a 20-item self-report measure of the degree of depressive symptoms experienced in the past week. Participants rate their responses using a five-point Likert scale and scores are recoded ranging from 0 to 3, with a higher score indicative of more severe depressive symptoms. The internal consistency score in the current study was acceptable (␣ ⫽ 0.78). The Body Areas Satisfaction Scale (BASS) is a 9-item subscale of the Multidimensional Body Self-Relations Questionnaire [21]. Participants rate the degree of satisfaction with specified body parts (e.g., face, thighs) and overall muscle tone, weight, height, and appearance using a fivepoint Likert scale ranging from 1 to 5. A higher score on the BASS represents greater satisfaction with one’s body. The internal consistency of the total BASS score in this study was good (␣ ⫽ .85). The Leisure-Time Exercise Questionnaire (LTEQ) [22] assesses self-reported mild, moderate, and strenuous leisure-time PA that is done for at least 15 minutes during a typical week. Consistent with previous researchers [23] and current exercise recommendations [24] we rephrased the instrument to assess leisure-time PA that is done for at least 30 minutes. A weekly PA index in metabolic equivalents (METs) is generated with the following formula: (5 ⫻ moderate bouts) ⫹ (9 ⫻ strenuous bouts). The LTEQ has been used previously to assess adolescent PA [25], and the test–retest value of the LTEQ with adolescents was reported to be .84 [26]. The Children’s Eating Attitudes Test (chEAT) [23] is a 26-item self-report measure of maladaptive or problematic eating attitudes in children. Participants rate their responses using a six-point Likert scale ranging from 1 to 6. A higher score is representative of more problematic or maladaptive eating attitudes and a cutoff of 20 is indicative of risk for eating disorder pathology (i.e., higher scores mean higher levels of negative eating attitudes). In the current study, the
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D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
internal consistency of the total chEAT score was excellent (␣ ⫽ .90). Design and procedure The University’s Institutional Review Board and the School District’s Board of Education approved this study, and informed consent was obtained in accordance with university guidelines (i.e., the students and their parents completed written informed consent forms). The response rate was 51.2% (681/1,329), which is similar to other studies examining health behaviors in adolescents [27]. Thirty participants did not report their weight to calculate BMI, and five students with incomplete data were eliminated from the analyses; thus the final sample size was 646. Data analyses Descriptive characteristics are given in Table 1. To examine weight status, participants were classified according to the guidelines published by the Centers for Disease Control and Prevention [19]. These guidelines suggest that a BMI percentile ⱖ85 and ⬍95 is classified as at risk of overweight and a BMI ⱖ95 is classified as overweight; however, the participants in this study who were at risk of overweight and who were overweight were examined as a single group. Also we excluded the participants in the underweight category (n ⫽ 8) from further analyses because of the small sample size. Therefore, to simplify the presentation and discussion of results, participants were classified as either normal weight (⬎5th and ⬍85th percentile; n ⫽ 455) or overweight (ⱖ85th percentile; n ⫽ 183). Pearson correlations were used to examine the associations among the study variables for the total sample and by sex and BMI status. To examine group differences on the study variables the nonparametric Kruskal-Wallis (K-W), Table 1 Characteristics of the study sample (N ⫽ 646) N Body mass index Normal weight Overweight Height (in) Weight (lb) Age Sex Female Male Race/ethnicity Caucasian/white Asian African American Hispanic/Latino Other Grade 8th grade 9th grade
646 455 183 646 646 675
% 71.0 29.0
Mean
Range
SD
21.96 20.01 27.10 64.63 130.8 14.28
(15–47) (15–26) (22–47) (55–74) (62–256) (13–16)
4.21 1.88 4.02 3.26 29.34 0.66
319 327
49.4 50.6
— —
— —
— —
571 32 14 9 49
84.6 4.7 2.1 1.3 7.3
— — — — —
— — — — —
— — — — —
330 316
51.1 48.9
— —
— —
— —
one-way ANOVA by ranks was used because the comparison groups were unequal (i.e., normal-weight group was larger than the overweight group); thus, the assumption of traditional parametric ANOVA was violated [28,22]. All statistical tests were conducted with alpha set at .05. To examine the contributions of depressive symptoms, body satisfaction, and PA for predicting negative eating attitudes, two hierarchical regression analyses by sex were conducted. The order and content of the blocks of variables were based on previous research [29] and regression analyses including sex interaction terms [30,31]. Eating attitudes (DV) was regressed on BMI (Block 1), depressive symptoms and body satisfaction (Block 2), PA (Block 3), and the interaction terms for BMI (e.g., PA*BMIgroup) in Block 4. Based on regression models with multiple predictor variables, and a priori power of .80 and alpha of .05, adequate power was obtained to conduct these analyses [32]. The tolerance values for the two regression analyses revealed that we had multicollinearity among our independent variables (values ⬎ .20). Thus, to reduce multicollinearity, we centered the variables (i.e., subtracting the mean for each predictor variable), which resolved this issue [33]. Results Correlations for study variables by sex and BMI status Pearson correlations among the psychosocial and behavioral variables for the total sample and across sex and BMI are presented in Table 2. High levels of depressive symptoms were associated with negative eating attitudes for normal-weight boys and both normal and overweight girls. Also, the normal-weight and overweight girls reporting low levels of body satisfaction also reported high levels of negative eating attitudes; however, this association was not significant for boys. Finally, normal-weight girls scoring high on PA also reported high levels of negative eating attitudes. However, this association was not significant for boys or overweight girls. BMI and sex differences across the study variables When participants were grouped by BMI, significant group differences were found for body satisfaction for boys [k-w (1) ⫽ 8.42, p ⬍ .001, 2⫽ .03] and girls [k-w (1) ⫽ 22.49, p ⬍ .001, 2⫽ .07] (Table 3), such that normalweight boys and girls scored significantly higher on body satisfaction than overweight boys and girls. No group differences were observed for depressive symptoms or eating attitudes for boys or girls; however, significant group differences were noted for PA among girls [k-w (1) ⫽ 3.71, p ⬍ .05, 2⫽ .01] such that normal-weight girls reported significantly more PA behavior than overweight girls. No BMI group differences were found for boys (p ⬎ .05).
D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
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Table 2 Correlations for the study variables by sex and body mass index (BMI) status Depression
Eating attitudes Total Normal weight Overweight Depression Total Normal weight Overweight Body satisfaction Total Normal weight Overweight a b
Body satisfaction
Physical activity
Total
Boys
Girls
Total
Boys
Girls
Total
Boys
.23a .23a .21b
.21a .27a .14
.26a .21a .31a
⫺.23a ⫺.21a ⫺.32a
⫺.04 ⫺.02 ⫺.19
⫺.30a ⫺.30a ⫺.35a
.08 .08 .08
.08 .08 .18
— — —
— — —
— — —
⫺.12a ⫺.12b ⫺.16b
⫺.09 ⫺.10 ⫺.09
⫺.17a ⫺.16b ⫺.31a
⫺.08b ⫺.08 ⫺.15
⫺.14b ⫺.15b ⫺.17
— — —
— — —
— — —
.29a .23a .40a
.37a .38a .39a
Girls .16a .17b .10 ⫺.03 ⫺.03 ⫺.16 .14b .03 .26b
p ⬍ .01 (two-tailed). p ⬍ .05 (two-tailed).
Predicting eating attitudes by sex Predicting eating attitudes for boys. In the first block of the model, BMI group explained 1% of the variance in eating attitudes (Table 4). When depressive symptoms and body satisfaction were included in the second block, an additional 7% of the variance was explained with depressive symptoms emerging as the only significant predictor. When PA was included in the third block, an additional 2% of the variance was explained, with PA and depression predicting eating attitudes and PA emerging as the strongest determinant. Finally, an additional 4% of the variance was explained when the interaction terms were included in the fourth block. Specifically, the interaction terms PA group*BMI classification and body satisfaction group*BMI classification significantly predicted eating attitudes. The main effects for BMI group, depression, and body satisfaction maintained their significant contribution; however the
interaction term for body satisfaction group*BMI classification emerged as the strongest determinant. To further examine the interactions for body satisfaction and PA, mean tertile splits were conducted. We examined the high PA score for normal-weight group (mean [M] ⫽ 79.92, SD ⫽ 13.51) and overweight group (M ⫽ 84.25, SD ⫽ 13.04); and low PA score for normal-weight group (M ⫽ 18.68, SD ⫽ 11.21) and overweight group (M ⫽ 11.68, SD ⫽ 8.79). Similarly, we examined the high body satisfaction score for normal-weight group (M ⫽ 35.46, SD ⫽ 2.77) and overweight group (M ⫽ 35.33, SD ⫽ 3.04); and low body satisfaction score for normal-weight group (M ⫽ 23.02, SD ⫽ 2.72) and overweight group (M ⫽ 22.08, SD ⫽ 3.31). Figure 1 illustrates that overweight boys in the high PA group reported more negative eating attitudes compared with normal-weight boys in the high PA group. Figure 2 illustrates that normal-weight boys in the low body satisfaction group reported more negative
Table 3 Mean and standard deviation (SD) scores for the study variables for all participants, by sex and body mass index group
All participants Total Normal weight Overweight Boys Total Normal weight Overweight Girls Total Normal weight Overweight
Depressive symptoms Mean (SD)
Body satisfaction Mean (SD)
Physical activity Mean (SD)
Eating attitudes Mean (SD)
6.29 (2.92) 6.24 (2.91) 6.26 (2.88)
27.77 (6.18) 28.45 (6.03)a 25.95 (6.09)b
43.56 (28.29) 44.29 (27.47) 41.14 (29.55)
5.33 (5.73) 5.29 (5.83) 5.84 (5.69)
6.37 (3.05) 6.31 (3.0) 6.31 (3.01)
29.35 (5.93) 30.06 (5.72)a 27.88 (6.12)b
49.97 (29.15) 50.69 (28.45) 49.02 (31.41)
4.31 (4.50) 4.28 (4.40) 4.79 (5.11)
6.21 (2.79) 6.19 (2.83) 6.19 (2.74)
26.23 (3.04) 27.09 (5.96)a 23.64 (5.22)b
37.52 (26.10) 38.86 (25.44)a 32.60 (24.88)b
6.35 (6.59) 6.21 (6.75) 6.99 (6.11)
Superscript letters indicate significant group differences (p ⬍ .05).
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D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145 Table 4 Hierarchical regression analyses predicting eating attitudes for boys and girls Variable Predicting eating attitudes for boys Block 1 BMI group Block 2 Depression Body satisfaction Block 3 PA Block 4 Depression*BMI group Body satisfaction*BMI group PA*BMI group Predicting eating attitudes for girls Block 1 BMI group Block 2 Depression Body satisfaction Block 3 PA Block 4 Depression*BMI group Body satisfaction*BMI group PA*BMI group
df
R2 change
.68
1,230
.01
8.01b
2,228
.07
F change
1
.05
2
.04
3
.04
.25b .26b ⫺.01 ⫺.08 5.05c
1,227
3.81
3,224
1.01a .38c .57a
.02 .56c
a
4
⫺.26
.04 ⫺.16 ⫺1.26a .51c
.71
1,245
.01
2,243
.12
.05 16.83b
10.33b .18
1,242
.04
3,239
.01
⫺.01
.004
.11
.18a .19a ⫺.27b ⫺.29b
.15 ⫺.22
.19a
.27 .05 ⫺.11 ⫺.09
Abbreviations. BMI ⫽ body mass index; PA ⫽ physical activity. 1-4 ⫽ standardized regression coefficients for Equations 1, 2, 3, and 4; df ⫽ degrees of freedom. a p ⬍ .01. b p ⬍ .001. c p ⬍ .05.
eating attitudes compared with overweight boys in the low body satisfaction group. Predicting eating attitudes for girls. In the first block of the model, BMI explained 1% of the variance in eating attitudes. When depressive symptoms and body satisfaction were entered in the second block, an additional 12% of the variance was explained. Both depressive symptoms and body satisfaction were significant determinants; however body satisfaction emerged as the strongest predictor. When
PA was entered in the third block, an additional 4% of the variance was explained, with depressive symptoms maintaining its significant contribution and body satisfaction emerging as the strongest determinant. Finally, an additional 1% of the variance was explained when the interaction terms, PA*BMIgroup, body satisfaction*BMIgroup, and Depression*BMIgroup, were included in the fourth block; however none of the main effects or interaction terms emerged as significant determinants.
Figure 1. Illustration of physical activity group*BMI classification for predicting boys’ scores on the Children’s Eating Attitudes Test (chEAT).
Figure 2. Illustration of the interaction of body satisfaction*BMI classification for predicting boys’ scores on the Children’s Eating Attitudes Test (chEAT).
D. Symons Downs et al. / Journal of Adolescent Health 41 (2007) 138 –145
Discussion The purpose of our study was to examine the collective influences of depressive symptoms, body satisfaction, and PA for determining the eating attitudes of adolescent boys and girls, and to examine the moderating influences of sex and weight status. In general the study findings illustrate that, among boys, weight status moderated the predictive contributions of body satisfaction and PA on eating attitudes. Specifically, overweight boys scored lower on body satisfaction and higher on PA compared with normal-weight boys. However this moderating influence was not observed for depressive symptoms among boys. Among girls the weight status did not moderate the existing associations among any of the psychobehavioral correlates for predicting eating attitudes; however, all three main effects significantly predicted eating attitudes. Several findings warrant further discussion. In support of our first hypothesis and previous research [4,9,10], depressive symptoms and body satisfaction were significantly associated with eating attitudes for girls, with body satisfaction emerging as the strongest correlate. Our findings are consistent with previous research [1]. For example, Johnson and Wardle [9] examined the longitudinal associations between eating attitudes and body satisfaction in a school-based sample of adolescent girls (ages 13–15 years), and found that body dissatisfaction was the strongest independent factor predicting eating attitudes. Thus identifying factors facilitating positive and negative body satisfaction is an important aspect of understanding negative eating attitudes among girls. Among boys, only depressive symptoms was associated with eating attitudes, suggesting that normal-weight boys reporting high depressive symptoms also reported more problematic eating attitudes. This finding is also consistent with previous research [31]. Therefore it is important to recognize that boys who report depressive symptoms may also be at risk for eating disorders. Because of the cross-sectional nature of this study, this relationship can also be interpreted that boys who report problematic eating attitudes may be at risk for depressive symptoms. As predicted in our second hypothesis, and consistent with previous research [8,11,19], boys scored higher on measures of PA and body satisfaction, and lower on negative eating attitudes compared with girls. This sex difference is not surprising, considering the increased emphasis on maintaining a thin or ideal body that increases girls’ risk for body dissatisfaction and pathologic eating behavior. However, it is important to note that the prevalence of body dissatisfaction and eating disorders may be increasing in boys [34], as they may desire a more muscular figure. Because of sex differences in body satisfaction, current measures are limited in that they only assess dissatisfaction with adiposity and fail to measure dissatisfaction with muscularity. Thus additional research
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on boys is warranted to confirm our study findings and to enable one to draw more conclusive evidence concerning the sex differences among adolescent boys and girls. In support of our third hypothesis and previous research [14], significant group differences were observed for body satisfaction for normal and overweight adolescents. Adolescence is a time of constant change, with intense pressure to belong. For example, young overweight adolescents have reported having fewer friends, being less liked by parents, being less happy, and being less attractive than their normalweight counterparts [35]. Along with these self-evaluative concerns during adolescence, there are increasing rates of obesity and eating disorders [36]. However, in contrast to our third hypothesis, there were no significant group differences observed for eating attitudes between normal and overweight adolescents. Collectively, these findings suggest that just being overweight during adolescence may not increase the risk for depressive symptoms or negative eating attitudes; however body satisfaction does appear to be influenced by weight status. That is, our findings demonstrated that compared with normal-weight adolescents, overweight adolescents exhibited lower body satisfaction, which may be the important psychological factor to target for intervention. For PA, group differences were observed with boys scoring higher than girls and normal-weight girls scoring higher than overweight girls. Consistent with the findings of Patrick et al [15], normal-weight girls reported more minutes engaged in PA compared with overweight girls. Existing literature has linked weight-based teasing to body dissatisfaction among overweight youth [37], which may pose a barrier to involvement in PA. In addition, compared with their normal-weight peers, overweight girls may have been less comfortable (i.e., physically, emotionally) participating in PA [38]. Although both overweight and normal-weight girls may have a desire to improve body satisfaction and to achieve ideal body, normal-weight girls may perceive fewer barriers to being physically activity than overweight girls (i.e., embarrassment, discomfort). It is important to note that dieting behavior was not assessed in this study; and this may confound these findings if PA was used as a means of dieting. Also, because the LTEQ assesses leisure activities by time spent in PA and intensity level, we do not have data on the specific types of activities for which adolescents reported time and intensity. Thus girls may not recognize that some of the activities they engage in are actually forms of PA (i.e., house chores), and therefore, may have underestimated the amount of time they spent in PA. In contrast to our fourth hypothesis, PA did not emerge as the strongest predictor of eating attitudes in adolescent boys and girls. Before the addition of the interaction terms, PA was a significant predictor of eating attitudes. However, this association depended on weight status such that overweight boys in the high PA group reported more negative
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eating attitudes than normal-weight boys, although overweight boys in the low PA group reported less negative eating attitudes than normal-weight boys. A similar interaction was observed for body satisfaction group and BMI classification for predicting eating attitudes. One potential explanation for these associations is that boys may have both a thin and larger body ideal in that they were striving to achieve a lean and muscular body through variations of PA and diet to meet societal ideals [8]. Alternatively, it is plausible that boys may have engaged in more resistancetype activities (e.g., weight training) and were not finished growing, and therefore had higher BMIs. Consistent with previous research [16], the main effect for depressive symptoms maintained its contribution, but there was no interaction with weight status for either boys or girls. Also, regardless of weight status, girls’ body satisfaction and PA equally predicted eating attitudes. Thus, to improve eating attitudes among adolescent girls, a universal intervention focused on increasing body satisfaction and PA behavior may be effective. However our findings suggest that factors predicting eating attitudes may vary among boys and girls; therefore interventions designed to prevent negative eating attitudes should be sex-specific. Although our findings contribute to the adolescent eating attitudes literature by including leisure-time PA in combination with depressive symptoms and body satisfaction, as well as studying the moderating influences of sex and BMI, there were study limitations. First, because of the crosssectional nature of the study, no causal inferences can be made about the influences of depressive symptoms, body satisfaction, and PA in predicting eating attitudes. Second, although PA was assessed with a valid and reliable measure, it was nonetheless obtained through self-report, which is inherently biased by social desirability. Third, only 3% of adolescents in this study scored above 20 (i.e., the clinical cut-off for eating attitude scores on the chEAT); thus, these findings may not be easily generalized to adolescent populations with a greater prevalence of clinically significant negative eating attitudes. Finally the study findings can only be generalized to white, middle-to-high income adolescent populations. In conclusion, sex and weight status differences appear to exist for the risk of negative eating attitudes during adolescence. Our study findings illustrate that eating attitudes are determined differently for boys and girls, and they demonstrate the need for sex-specific interventions to promote healthy eating attitudes during adolescence. Although most of the research on eating attitudes has been focused on girls, the present study suggests that adolescent boys and girls are at similar risk for negative eating attitudes. Future research is warranted to understand how dieting, the thin ideal, and various types of PA may affect these associations in adolescent boys and girls [39].
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