As hypothesized and consistently with previous studies, the girls were less satisfied with their bodies than boys were with theirs [4
]. On closer examination, the girls expressed the greatest satisfaction with their bodies when they were underweight. The girls who were overweight or of normal weight expressed lower body satisfaction. This finding is in line with previous research documenting the impact of a greater body mass on body dissatisfaction in adolescent girls [6
]. Interestingly, a recent study indicated that body satisfaction was protective against increased body mass, even among girls who were overweight. Findings such as this point to the importance of helping adolescent girls, regardless of their size, to develop a positive sense of their bodies [42
In some previous studies among adolescent boys, the relationship between body dissatisfaction and body mass has been described to be quadratic, which indicates that boys express most dissatisfaction with their bodies when they are either below or above average weight and most satisfaction when they are of average weight [4
]. We also found a significant quadratic component, but LOWESS regression described the nonlinearity better. In fact, the curve had an inverse L-shape, indicating that body dissatisfaction was related to being overweight or obese, but not to being underweight. Age does not explain the difference, since a quadratic component has been described in both younger and older boys than those of our sample [4
]. However, cultural norms might give an explanation for this difference: a muscular male body ideal may not be strong enough to cause body dissatisfaction in Finnish underweight boys in transition from early to mid-adolescence. This hypothesis should, however, be tested in future studies.
As hypothesized, self-esteem and body dissatisfaction were negatively correlated in both genders, but the correlation was stronger among the girls. From the perspective of clinical work, the findings highlight the importance of strengthening the self-esteem of adolescents expressing abnormal eating, which in turn may reduce their body dissatisfaction and consequently lower the risk of developing clinical eating disorders [43
A normal eating pattern was significantly more prevalent among the boys than the girls in our study, which is in line with the fact that both clinical eating disorders and subclinical eating pathology are typically problems of young females [44
]. The relationship between eating habits and body dissatisfaction was found in both genders, but, as hypothesized, it was stronger among the girls. In line with two previous studies, the adolescents self-reporting abnormal eating habits were less satisfied with their bodies than those describing normal eating habits [25
]. We found that the girls and boys reporting abnormal eating showed higher BMI values than adolescents self-reporting normal eating. According to a previous follow-up study among adolescents, dieting and unhealthy weight control behaviours predicted greater body mass increases in females and males, as compared with cases with no such behaviour. Associations were found in both overweight and non-overweight participants [46
]. Research is needed to assess whether helping adolescents substitute dieting and unhealthy weight control behaviours with healthier behavioural patterns results in long-term improvements in weight status [46
The prevalence of overweight and obesity in adolescence has been reported to vary between 10 % and 20 % in most European countries, and consistently with this was approximately 11 % among the girls and 15 % among the boys in the present study [47
]. Our results were also in accordance with the findings of a study on a nationally representative sample of Finnish 14-year-old girls and boys [49
]. In both the national study and the present investigation, overweight and obesity appeared to be more prevalent among boys than girls.
The strength of the present study was its scale covering 24 secondary schools in the city of Helsinki.
The overall participation rate of the present study was approximately 60 %. A traditional nationwide school survey carried out biannually in Finnish comprehensive schools (grades 8th and 9th) with the same data collection method has repeatedly reported a participation rate of approximately 80 % [50
]. Consequently, the participation rate of the present study cannot be regarded as excellent or good, but we consider it acceptable. Unfortunately, we were unable to specify any attributes of the dropout group. Nonetheless, it is possible that the adolescents with the most marked eating problems might have refused to participate in the study because the study methodology included weight measurements performed by school nurses. The BMI values used in the present study were calculated from measurements taken by professional school nurses rather than self-reported values, as self-reported data are known to underestimate the prevalence of being overweight [51
The body dissatisfaction subscale of the EDI was used to measure body dissatisfaction in this study. It is a widely used questionnaire for both girls and boys. However, it does not contain questions about the desire to be bigger, which is a factor relevant to some adolescent boys [12
]. For this reason, it has been speculated that the EDI is perhaps not an ideal measure to examine the correlates of the desire to gain weight [15
]. Nevertheless, there is evidence of its usefulness in scoring body dissatisfaction in boys [31
]. One must bear in mind that the assessment of the eating habits was self-reported and limited to one question. Consequently, such data do not necessarily reflect actual eating behaviours but subjective ideas or memories of eating habits. However, Keski-Rahkonen et al. have previously used the same question with same response options in their large study on Finnish twins [54
]. Also, the number of underweight boys was small and the results must be interpreted with caution.