Lifestyle and dietary habits have dramatically changed in the Iranian population in the last 20 years. This revolution was associated with an increased prevalence of overweight and obesity in all age groups, especially teenagers. However, this revolution is a complex problem around the World (1). Unhealthy diet in childhood is related to obesity development, type 2 diabetes, cancer, and other chronic diseases later in the lifetime (2-4). Adolescence is the most important period of life that can guarantee the health or disease during the lifetime (5).

The teenage group is 20% of the total population worldwide 85% of which live in developing countries (6). Therefore, it can be said that teenage girls are approximately 10% of the total population in the world. Moreover, sufficient nutrition is very important for this age group as future mothers (7). The characteristics of physical and social environments are effective in forming nutritional behaviors in children and adolescents. The teenagers are more interested in eating foods of higher availability irrespective of the effects of socioeconomic and cultural factors on food choices. In addition, food structure is an important factor in the formation of dietary patterns (8).

The present nutritional behaviors in teenage girls (as future mothers) affect their present and future health in addition to the influences on having healthy children and families in the future (9-14). According to the results of some studies, it was shown that the increase in the level of health problems in the community in developing countries is related to poverty and lack of awareness regarding healthy principles among girls (14-17). Based on the findings of a study in Iran it was reported that unhealthy dietary behaviors
are common among Iranian children (18). Demographic characteristics (i.e., age, sex, race, and socioeconomic status [SES]) as important factors are associated with dietary intake and dietary pattern in children (19). Although, self-efficacy is a major factor to form a healthy dietary pattern it can be said that it has strong effects on food choices (20).

The results of some studies about self-efficacy revealed that people with no self-confidence about their abilities to perform a particular behavior cannot perform it or unlikely perform it, that is contrary to the individuals who are self-confident. The increase of self-efficacy may be induced by self-confidence and may be a good predictor to perform healthy behaviors in people. Sometimes, self-efficacy explains more than 50% of behavior variations. Lifestyles and dietary habits play important role in the teenager`s health. Overall, shaping the behaviors in an individual refers to the nutritional behaviors of the family and availability of healthy food, as well as nutritional behaviors that are associated with dietary self-efficacy (21-24).

The results of some studies show that dietary self-efficacy is a mediator between favorite foods and food choices and dietary patterns (25, 26). Based on the evidence it was revealed that self-efficacy is an important factor to increase efficacy in nutritional education programs and change dietary patterns. Furthermore, self-efficacy induced behaviors correlate with dietary intake (27, 28). Although the results of the aforementioned studies suggested that dietary self-efficacy affects food choices, they provide limited information about the association between dietary self-efficacy and common dietary patterns. Consequently, this study aimed to evaluate the prevalence of unhealthy dietary patterns and dietary self-efficacy and the related association in teenage girl students.

Materials and Methods

The present study was a cross-sectional study conducted on 236 female high school students in Mashhad, Iran, in 2016. The sample size was determined based on a similar study investigating the status of nutrition and self-efficacy (29) using a power of 80% and
an alpha error of 5%. After obtaining the permission of education officials in Mashhad the study was conducted in April 2016. According to cluster random sampling method, separate clusters were considered based on district no. 6 in Mashhad from which one cluster was randomly selected.

There were six high schools in this cluster from each school one class was chosen. Finally, a total of 250 subjects (age range: 13–15
years) were selected using the mentioned
sampling method. The written consent forms
were obtained from students’ parents for participation. The inclusion criteria were all girls within the age range of 13-15 years present at school at the time of sampling. Moreover, students with dietary disorders, dietary restraints, or particular diets were excluded from the present study.

The nutritional status was evaluated using a standard questionnaire, namely FFQ (Feed Frequency Questionnaire). It is a valid and reliable self-report food frequency questionnaire with the validity (correlation coefficients) and reliability (intra-class correlation coefficients) ranged from 0.49%-0.82% and 0.66%-0.89% for all foods, respectively (30) to evaluate dietary intake and determine average consumption and the frequency of 148 food items during the last month.

Two healthy and unhealthy dietary patterns were identified based on the previous studies (31) The unhealthy group has high consumption of mayonnaise, refined cereals, French fries, non-refined cereals, high-fat dairy, organ meats, as well as red or processed meats, and the healthy group has high consumption of vegetables, legumes, potatoes, fruit and fruit juices, liquid oils and olive oil, fish, low-fat dairy and poultry meat (31). A valid and reliable questionnaire was utilized for the assessment of self-efficacy (Cronbach's alpha coefficient: 0.8%) (32). In this study, the validity of the self-efficacy questionnaire was approved by ten health education professors.

Self-efficacy questionnaire included 6-item Likert scale items (very low, low, moderate, high, and very high) scored from 0-4. The total score obtained in the three groups were reported as more than 66.7% )high self-efficacy(, 33.4%-66.6% (moderate self-efficacy(, and less than 33.3% )low self-efficacy( (33). In addition, for
the determination of reliability, self-efficacy questionnaire and FFQ were given to 27 students prior to the study rendering Cronbach's alpha coefficients of 0.88% and 0.7% for self-efficacy questionnaire and FFQ, respectively.

After data collection, all the analyses were performed using SPSS software (version 16) and the normality of data was checked using Kolmogorov-Smirnov test. All the obtained data were reported as mean and standard deviation compared between the two groups by the unpaired t-test. Categorical variables were compared using Chi-square test or Fisher’s
exact test. P-value was statistically considered significant for all the tests (P=0.05).

Results

A total of 236 teenage girls were recruited in this study with demographic characteristics summarized in Table1. The prevalence of unhealthy dietary patterns was reported as 65.3% in teenage girls. Moreover, high, moderate, and low levels of self-efficacy were 35.8%, 56.9%, and 7.3%. Furthermore, the distribution of dietary self-efficacy score was normal and mean score of dietary self-efficacy was 13.96±4.55 ranged from 0-24. There was no significant difference between maternal age and birth rank between the groups with healthy and unhealthy dietary patterns (P>0.05). However, a statistically significant difference was observed in paternal age and family size between the two dietary patterns (P<0.05) (Table 2).

Dietary pattern correlated with paternal (P=0.031) and maternal (P=0.047) educational level, as well as father’s (P=0.004) and mother's (P=0.012) occupations. Although there was no association between the educational level of parents and dietary patterns (father, χ2=4.098, P=0.251 and mother, χ2=1.74, P=0.627). In addition, no relations were observed between paternal occupation and dietary patterns (χ2=0.589, P=0.905), as well as the level of family income and dietary patterns (F=4.490, P=0.210). Only maternal profession significantly correlated with dietary patterns (F=8.16, p=0.05).

Moreover, there was an association between dietary patterns and dietary self-efficacy (P=0.005), and dietary self-efficacy score was higher in the group with healthy dietary patterns, compared to the group with unhealthy dietary patterns. Nonetheless, there was no significant relationship between the levels of dietary self-efficacy (high self-efficacy, moderate self-efficacy, and low self-efficacy) and dietary patterns (χ2=1.130, P=0.568). Self-efficacy score was analyzed as a dependent variable and the obtained results revealed that the mean difference of dietary self-efficacy score was not statistically significant in the parental level of education (P>0.05).

Furthermore, the mean difference of dietary self-efficacy score was statistically significant in the different classes of father’s occupation

 Discussion