Factors Associated with the Risk of Eating Disorders

Research Article

Ann Nutr Disord & Ther. 2015;2(2): 1021.

Factors Associated with the Risk of Eating Disorders

Álvarez-Malé ML1,2*, Bautista-Castaño I1,3,4 and Serra-Majem L1,3,4

¹Department of Preventing Medicine and Public Health University of Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain

²Association Gull-Lasègue for the study and the treatment of the Anorexia and Bulimia in Canarias, Las Palmas de Gran Canaria, Spain

³Nutrition Research Group, Research Institute of Biomedical and Health Sciences, University of Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain

4Ciber de Fisiopatología de la Obesidad y Nutrición (CIBER OBN), Instituto de Salud Carlos III, Madrid,Spain

*Corresponding author: Álvarez-Malé ML,Departament of Clinical Sciences, University of Las Palmas de Gran Canaria, CP. 35080, Las Palmas, Spain

Received: February 02, 2015; Accepted: March 03, 2015; Published: March 05, 2015


Objective: To analyze factors associated with the risk of Eating Disorders (EDs), like the Mediterranean diet adherence, physical activity and weight status, in participants between 12 and 20 years old; and to obtain data of prevalence of risk of developing an ED.

Methods: 1342 adolescents were selected from educational centers on Gran Canaria, Spain. The sampling technique was sampling by clusters, and the sample unit was the classroom. Risk of EDs was measured by EAT-40 questionnaire. Sociodemographic variables, weight status, physical activity, and adherence to Mediterranean diet were also evaluated. To evaluate the associated factors of EAT, positive test logistic regression analyses were used, controlling for confounding variables.

Results: The prevalence of risk of ED was 27.42% (33% of girls, 20.6% of boys). The following variables were associated with an increased risk of developing an ED: excess weight versus normal weight (OR = 2,32; 95% CI: 1.58- 3.41), a low adherence to the Mediterranean diet versus a high adherence (OR=1.77; 95% CI: 1.06-2.94), a good level of physical activity versus a moderate level (OR=1.790; 95% CI: 1.08-2.96), and have been on diet in the past year (OR=5.97; 95% CI: 4.12-8.66).

Conclusion: The prevalence of risk of ED in Gran Canaria is especially high compared to other national and international studies. A high adherence to Mediterranean diet and a moderate level of physical activity attenuate the risk of ED in adolescents.

Keywords: Eating disorders; Risk factors; Epidemiology; EAT-40; Crosssectional descriptive research


Eating Disorders (EDs) are biopsychosocial pathologies with severe physical complications [1]. They are characterized by a difficult and prolonged treatment time, risk of chronicity, relapse, anxiety related to social constraints, risk of obesity in later life, depression, suicide attempts, anxiety disorders, substance abuse, and high comorbidity [2-4]. In addition, all ED have an elevated mortality risk, anorexia the most remarkable [5,6].

Given the severe impact of these diseases, numerous epidemiological studies have been developed in recent decades that attempt to measure the extent of these disorders and inquire about risk factors that may be related to the disorders [7]. Although there are clear differences and a variety among these studies, it can be considered there is a risk of ED of between 4 and 12% (some studies indicate up to 25%), with a prevalence of ED diagnosis of between 1 and 5% [8].

Although the percentage of ED diagnosis is relatively low, many women seem to be at risk of developing it [9,10]. Moreover, in contrast to previous stereotypes, epidemiological studies have shown that EDs affect all ethnicities and socioeconomic groups [11,12].

Therefore, the risk factors associated with these problems can also vary depending on social and cultural differences [13]. In Spain, and especially in the Canary Island, the obesity prevalence among children and adolescents is very high, particularly among Canarian adolescent girls [14].

EDs are common in adolescent population [15,16]. These pathologies, together with overweight and obesity, are important health concerns in adolescents [15], because excess weight has been associated with altered dietary patterns [17,18].

Despite the existence of some longitudinal studies, there is still no consensus about the determinant factors in the development of these pathologies in adolescence. In addition, many of the studies have limitations of the sample size or the inclusion of a single class [19].

Some studies like the European ProYouth programme, focused on the promotion of mental health and the prevention of ED among young people, have concluded that those individual who had considerable concerns about their weight are at risk for developing ED [20]. Other, like the published by Morales et al. in 2014, have found that risk factors of ED were male gender, age > 14 years, body image dissatisfaction, family dysfunction, depressive symptoms and perceived stress [21]

It has been argued that it is important to identify specific risk and protective factors for the development of disturbed eating [22].

In the Canary Island, there are some studies about characteristics associated to EDs [23,24] with different results about the influence of age, gender, physical activity, previous losing diets or excess weight. None of these studies have evaluated the influence of Mediterranean diet adherence. Some studies have found an inverse association between adherence to a Mediterranean diet and the risk of depression [25]. Because of that, it would be interesting to investigate the relation between dietary patterns and EDs prevalence.

Therefore, the objectives of this paper are to analyze the association between different factors like Mediterranean diet adherence, physical activity patterns and weight status and the risk of developing an EDs, and to obtain data of prevalence of risk in a population between 12 and 20 years old from the island of Gran Canaria, Spain. This will allow us to identify those individuals most likely to have EDs, in order to design targeted programs for high-risk individuals.

Material and Methods

Participants and procedure

This study was reviewed and approved by the Ethics Committee of the University of Las Palmas de Gran Canaria and done in accordance with the Declaration of Helsinki [26]. All participants or (in the case of minors) their legal representatives signed an informed consent agreeing to participate in this research, following the LOPD 15/1999 [27].

The sample consisted of 1342 adolescents with a mean age of 15.0 (SD = 2.1 years). All the participants were from compulsory secondary education (aged 12 to 16; known in Spain as Educación Secundaria Obligatoria – ESO) to post-compulsory education at high school (aged 16 to 18; known in Spain as Bachillerato) or vocational training enrolled in 15 educational centers on the island of Gran Canaria (11 public educational centers and 4 private educational centers).

We started with a pilot study in an educational center to ensure that all participants understood and did correctly all the tests in the stipulated time.

The sampling technique was sampling by clusters, the sample unit was the classroom; then, we contacted the centers and met with heads or school counselors to explain what the work was to consist of, to distribute the informed consent, and to coordinate the activity. Once the date was specified, the team moved to the participating centers for the implementation of the different tests. The time required for conducting these tests was approximately 40 minutes, and they were at all times supervised by a team member. Later, the adolescents were weighed and measured without shoes, jackets, or heavy coats.


Sociodemograhic questionnaire:

An ad hoc sociodemographic questionnaire was used, which collected information such as gender, age, educational level of parents, family illnesses reported by participants, being on diets, and so on.

Risk of Eating Disorder (EAT-40):

As a screening tool to determine whether or not there was risk of developing an eating disorder, the EAT-40 (Eating Attitudes Test) of Garner and Garfinkel was used [28]. The EAT-40 has been a commonly used screening instrument for EDs in epidemiological research. It measures the characteristic symptoms and concerns of EDs, such as the attitudes, feelings, and behaviors related to food, weight, and exercise. It is suitable for application from the age of 12, or from the first period in women. The cutoff proposed by the original authors is 30 (Sensivity: 100%, Specificity: 97%) [28]. With this same cutoff, in the Spanish validation study, sensitivity drops to 67.9 %. Therefore, Castro, Toro, Salamero, and Guimerá [29] proposed an alternative cutoff of 20 to be used in the Spanish environment, bringing the sensitivity up to 91%.

Moreover, they identified three factors. Factor I, significantly loaded, contains almost all items and can be identified as diet and food preoccupation. Factor II contains most of the items related to the perception of experiencing social pressure and eating distress. Factor III mainly contains issues related to psychobiological disorders. This was the version used in our study.

The EAT-40 questionnaire consists of 40 items, which distinguish between ED patients and the normal population. Responses are rated on a 1 (Always) to 6 (Never) spectrum. Items 1,18,19,23 and 39 are scored: 6=3 points; 5=2 points; 4=1 point; 3, 2, or 1=0 points. The remaining items are scored: 1 = 2 points; 2=2 points; 3=1 point, and 4, 5, or 6=0 points. Therefore, the total possible scores of the questionnaire ranges from 0 to 120 points.

Physical Activity (Krece Plus):

The Krece Plus [30] questionnaire was used to evaluate the physical activity habits of the adolescents. This validated [30] test consists of 2 questions that assess the number of hours per day that the subjects performed sedentary activities like watching TV or playing video games, and the number of hours per week dedicated to physical activity. So, it is an index that allows a fast screening of the level of activity or inactivity of the participants. Each question has 6 possible answers and the scores range from 0 to 5. The maximum total value of the test is 10 and the minimum is 0. According to this, overall score are classified into 3 categories corresponding to their level of physical activity:

Good: score ≥ 9 for boys, ≥ 8 for girls

Moderate: 6–8 points for boys, 5–7 for girls

Poor: values ≤ 5 for boys, ≤ 4 for girls.

Adherence of Mediterranean diet (Kidmed):

The Kidmed Questionnaire [31] was used to measure the degree of adherence to the Mediterranean diet. It consists of 16 items. Each question is answered in the affirmative or negative (yes/no). It includes 12 items showing a positive attitude to the Mediterranean diet, which added 1 point if the subject responds positively; while 1 point is subtracted if the subject responds positively in those questions that have a negative connotation for the Mediterranean diet. From the total scored, three categories are obtained:

High adherence: scores ≥ 8 (and optimal adherence to the Mediterranean diet)

Intermediate adherence: scores between 4–7 (need to improve eating patterns to fit the Mediterranean model)

Low adherence: scores ≤ 3 (a very low quality diet where adherence is poor).

Anthropometric measures:

To weigh the participants we used a scale ranging from 0 to 150 kg with a precision of 200 g. For the measurement of body height a Holtain stadiometer (Holtain Ltd., Dyfed, UK) with an accuracy of 1 mm was used. Waist circumference was measured with a metal, flexible but inextensible tape (Holtain Ltd., Dyfed, UK) on a 0.1 cm scale.

Growth reference of the WHO [32,33] were used to establish the weight status of the adolescents, following this criteria:

Data Analysis

The SPSS statistical package (version 19.0. for Windows) was used throughout for the analysis. Descriptive analyses of the variables used the test of proportions for qualitative variables, measurements of central tendency (mean or median), and measures of dispersion (standard deviation – SD) for quantitative variables. Bivariate analyses of the proportionality of distribution of categorical variables were estimated using the χ test. For continuous variables, we used the Kolmogorov–Smirnov test to check that the variables were normally distributed. Normality was accepted as p > 0.05. For comparisons of continuous variables in which the distributions were normal, the comparisons of absolute means between groups were assessed with Student’s T test. For comparisons of variables in which the distributions were non-normal, the comparisons of absolute means between groups were made with the nonparametric Wilcoxon test of the sum of the ranges.

To evaluate the factors associated with the EAT, positive test logistic regression analyses was used. The studied independent variables were: gender, age, being on a diet in the past year, weight status, physical activity, obesity in parents, alcoholism in parents, mother educational level and father educational level. Significance was set at p < 0.05.


The final sample consisted of 1342 participants, of which 45.2% (n = 606) were boys and 54.8% (n = 736) were girls; 98.5 % (n = 1322) were aged between 12 and 20 years and the level of education received ranged from ESO to bachillerato and vocational training. A total of 913 participants (68%) were in ESO, 399 (29.8%) were at bachillerato, and 30 (2.2%) were enrolled at vocational training institutions. With reference to the educational level of parents of adolescents, we found that 58% (n = 567) of the fathers and 59.8% (n = 632) of the mothers had secondary or higher education, compared to 42% (n = 411) of fathers and 40.2% of mothers (n = 425) who had a low educational level.

Regarding the level of adherence to the Mediterranean diet by participants, the mean score for the total population was 5.83 (SD = 2.52), and the mean for girls was 5.56 (SD = 2.47) and that for boys was 6.15 (SD = 2.54) (p < 0.001). In the case of Krece Plus (physical activity), we found an average of 6.05 for boys (SD = 2.17) and 5.06 (SD = 2.31) for girls, and the difference was also significant (p < 0.001). The average score for the total population in this test was 5.51 (SD = 2.30).

For the EAT-40 test, of the 1342 participants, 368 (27.4 %) scored above the cutoff set at 20 (18.11% of girls, 9.31% of boys), and were therefore considered at risk of developing an ED. Table 1 shows the distribution of the sample according to the risk of ED and their socio-demographic characteristics. Regarding gender, girls were at a significantly higher risk than boys (33% versus 20.6%; p < 0.001). In relation to age, the younger group (≤ 13 years) had the highest percentage of risk at 32.8% (n = 101).