Introduction

Health literacy is defined as the ability of an individual to find, understand, and use health-related information in order to be healthy and to maintain health status (Joulaei et al. 2018). It has been indicated that individuals with a high level of health literacy make healthier choices and behave more carefully about healthy nutrition throughout their lives (Lee et al. 2022). A healthy population is based on a healthy lifestyle and diet. Adolescence is a period where lifestyle and individuals’ behaviors are shaped. It has been reported that the effects of these behaviors shaped during this period continue throughout life and affect health behaviors (Fleary et al. 2018; Sukys et al. 2019).

School health nurses, who have the opportunity to access all groups in the society, have an important role in terms of intervention for developing healthy nutrition and health literacy among the adolescents. They also have significant responsibilities as a leader role in the execution of health promotion programs for adolescents and in the curriculum development studies in cooperation with school management, teachers, and parents (Ayaz Alkaya and Kulakçı 2021). In the previous studies that were carried out to evaluate the effects of health literacy level on eating behaviors, dietary knowledge, eating attitudes and preferences were determined to be positively affected among the individuals who had a sufficient level of health literacy (Kuczmarski et al. 2016; Lee et al. 2022). In a study including younger adult groups, both food literacy and health promotion literacy were observed to be associated with healthy dietary habits (Lee et al. 2022). Moreover, Soylar and Kadioglu (2020) reported in their study that slightly overweight and obese states were increased among the individuals with an inadequate level of health literacy. A study on poor health literacy and increased body weight detected a correlation between health literacy and body mass index (BMI); and determined that BMI decreased as health literacy levels increased (Michou et al. 2018). Also in their study, Park et al. (2017) found that health perception was disturbed among the adolescents with a low health literacy level, and they were found to tend toward unhealthy diets.

This study was carried out to determine the relationship between health literacy levels and eating attitudes of adolescents.

Research questions

  • 1. What are health literacy and eating attitude levels of adolescents?

  • 2. Do sociodemographic characteristics of adolescents affect their health literacy and eating attitude levels?

  • 3. What is the relationship between health literacy levels and eating attitudes of adolescents?

Methods

Research type and place of the study

This descriptive, cross-sectional, and correlational study was carried out with students studying in the high schools located in the center of a district in the northern part of Turkey between February–March 2022.

Participants

The universe of the study consisted of 1931 adolescents aged between 14–18 years old who were studying at four high schools that were not shut down during the COVID-19 pandemic. It was aimed to attain the whole universe for sample selection; however, the study was completed with 79% of the universe (1519 adolescents) excluding the students who did not attend school, who could not be contacted, who did not want to participate in the study, and who filled out the questionnaires incompletely.

Data collection instruments

Personal Information Form, Turkish Health Literacy Scale-32, and Eating Attitudes Test were used to collect data.

Personal information form

This form was prepared by the researcher in accordance with the literature; and consisted of six questions, including age, gender, weight, height, dietary status of adolescents, and the sources they access to achieve health.

Turkish Health Literacy Scale-32 (THLS-32)

This scale is based on the framework established by the Consortium Health Literacy Project European; and it was developed by Okyay et al. (2016) to determine health literacy level among literate individuals aged older than 15 years old. THLS-32 was structured as a 2 × 4 matrix based on two dimensions. Accordingly, this matrix is composed of a total of eight components, including two dimensions (healthcare and disease prevention/health promotion) and four processing stages (access, understand, appraise, apply). Each item is marked as “1. Very easy, 2. Easy, 3. Difficult, 4. Very difficult” in the assessment of scale. Total score of the scale is calculated with an index formula ((arithmetic mean-1)x(50/3)) to take a value between 0–50. While 0 indicates a minimum level of health literacy in the scale, 50 points show a maximum level of health literacy. Health literacy is classified under four categories based on the index scores calculated. The score range of 0–25 was defined as “inadequate,” > 25–33 as “limited,” > 33–42 as “adequate,” and > 42–50 as “excellent” health literacy. Cronbach alpha values were calculated as 0.88 for “healthcare,” 0.86 for “disease prevention and health promotion” and 0.93 for general scale. In this study, Cronbach alpha levels were found as 0.87 for “Healthcare,” 0.91 for “disease prevention and health promotion,” and 0.93 for general scale.

Eating Attitudes Test (EAT-26)

This is the short form of Eating Attitudes Test-40 which was developed by Garner and Garfinkel (1979); and it was revised by Garner et al. (1982) as including 26 questions. The Turkish validity and reliability study of this test was carried out by Erguney-Okumus and Sertel-Berk in 2020. The participants are asked seven questions regarding their demographic information, 26 questions regarding their eating habits, and five questions regarding their eating behaviors in three different parts in EAT-26 (A-B-C). Only the part including 26 items regarding eating habits in the scale was used in this study. In the original study of the scale, a three-subscale construct was reported, including dieting, bulimia and food preoccupation, and oral control. The scores of 20 and above indicate a deterioration in eating attitudes. Cronbach alpha coefficients were reported as 0.90 for the scale, 0.90 for dieting, 0.84 for bulimia and food preoccupation, and 0.83 for oral control. In this study, Cronbach alpha coefficients were calculated as 0.75 for total scale, 0.88 for dieting, 0.56 for bulimia and food preoccupation, and 0.64 for oral control.

Data collection

Data were collected from the students studying at high schools by a survey method between the dates indicated by the researchers. Data collection instruments were distributed to the students after providing necessary explanations; and data collection lasted for approximately 15–20 min.

Data analysis

The SPSS 21.0 statistical package program was used to analyze data. Parametric Independent samples t test, ANOVA test, and Pearson correlation test were used for the data analysis. Number, percentage, mean, and standard deviation were used for descriptive statistics. The differences between two groups were analyzed by t test; and ANOVA test was used to compare the differences between the variables in three and more groups. The correlations between scale scores were analyzed using the Pearson correlation test. The statistical significance level was assessed as “0.05” for all comparisons.

Results

Of the adolescents surveyed, 27.6% were 17 years old, 57.7% were female, and 83.4% stated that they accessed health-related information on the internet. Also, it was found that 85.1% did not diet previously and 66% had a normal BMI value (Table 1).

Table 1 Sociodemographic characteristics of the adolescents (n = 1519)

Mean score of the adolescents from health literacy scale was found as 33.68 ± 10.33. While their mean score from Healthcare dimension was calculated as 12.95 ± 2.84, it was calculated as 11.58 ± 3.35 for disease prevention and health promotion. Of the adolescents surveyed, 31.3% had a sufficient level of health literacy, whereas 28.8% had a problematic-limited level of health literacy. Mean eating attitude score of the adolescents was calculated as 12.20 ± 12.24. For the subscales, mean scores were found as 6.41 ± 7.11 for dieting, 1.95 ± 3.26 for bulimia/food preoccupation, and 3.84 ± 4.17 for oral control. When eating attitudes were examined, the rate of adolescents with a normal eating attitude was found as 79.6%, whereas this rate was found to be 20.4% for those with disordered eating attitudes (Table 2).

Table 2 Descriptive statistics for health literacy and eating attitude levels of the adolescents

Positive but very weak correlations were found between age variable and mean total scores of Health Literacy and Eating Attitude Scales (p < 0.01) (Table 3).

Table 3 The correlation between age variable and mean scores of health literacy scale and eating attitudes test

It was determined that total mean scores of the adolescents from the Eating Attitudes Test were significantly different based on gender, BMI, and the presence of any previous diet; male and obese adolescents and those who dietted previously were found to have higher mean scores (p < 0.05) (Table 4).

Table 4 Comparison of total mean eating attitude scores of adolescents based on some characteristics

Bulimia/Food Preoccupation subscale of the Eating Attitudes Test was found to have a negative and very weak correlation with total mean score of Health Literacy Scale and its Disease Prevention and Health Promotion subdimension (p < 0.05) (Table 5). Also, a positive but very week correlation was found between Disease Prevention and Health Promotion subdimension of Health Literacy Scale and Oral Control subscale of the Eating Attitudes Test (p < 0.05).

Table 5 The correlations between health literacy scale and eating attitudes test and their subscales

Discussion

In this study which was carried out to determine the relationship between healthy literacy levels and eating attitudes of the adolescents, 45.5% of the adolescents were found to have a problematic-limited and inadequate level of health literacy. The study by Kirsan and Ozcan (2021) reported that 89% of adolescents had an inadequate level of health literacy. Moreover, 25.5% of adolescents were observed to have an inadequate health literacy level in the study by Ran et al. (2018). Some other studies have reported that adolescents mostly have problematic-limited and a moderate level of health literacy (Sukys et al. 2019; Caldwell and Melton 2020; Ayaz Alkaya and Kulakçı 2021).

In this study, it was determined that 20% of the adolescents had negative eating attitudes. Various rates of negative eating attitudes (4–47.2%) have been reported in the studies conducted with adolescent groups (Tural Buyuk and Duman 2014; Chen et al. 2022).

It was also determined in the study that health literacy levels increased with age. Some studies including adolescents also indicated that health literacy levels increased with age and grade level (Jafari et al. 2021; Perry et al. 2017).

It was also found in the study that adolescents had negative eating attitudes as their ages increased. In the study by Ferreira et al. (2021), it was shown that 10th grade adolescents had a higher health and food literacy. It has been suggested that adolescents prepare for university exam during the last grades and, thus, they may tend to poor dietary habits due to the future anxiety they experience during these years.

In the current study, it was determined that male adolescents had more negative eating attitudes compared to female adolescents. In some other studies, female adolescents were found to have more negative eating attitudes (Chen et al.2022; Bulduk et al. 2018). Unlike other studies in the literature, the mean score of the male participants was found to be higher in this study. The possible reasons of this may be the facts that male adolescents tend to eat prepared foods since they spend more time outside with the effect of cultural factors in our society and, thus, they are likely to have negative eating habits.

In the study, it was found that the adolescents who were classified as obese and who applied a diet previously had more negative eating attitudes. Previous studies have also reported that overweight and obese adolescents have negative eating attitudes (Hayes et al.2018; Rostampour et al. 2022).

This current study also revealed a weak correlation between health literacy levels and eating attitudes of the adolescents. In the study by Keikha et al. (2021) which was carried out with adolescents, it was determined that health literacy and eating attitudes were correlational, and education given affected both health literacy and eating attitudes in a positive way. Moreover, Boberová and Husárová (2021) reported that adolescents with a low health literacy level were more likely to have negative eating attitudes, especially when they perceived themselves as fat. Again, it was found in previous studies that there was a positive correlation between nutrition–exercise behaviors and health literacy levels of the adolescents; and obese individuals had a lower health literacy (Adewole et al. 2021; Ayaz Alkaya and Kulakçı 2021; Li et al. 2022).

Limitations of the study

The current study has some limitations. First, it was carried out with adolescents studying in only one district and did not include the other adolescents living in Turkey. Second, the results based on the statements of adolescents were interpreted in the study. Third, previous disease history of the adolescents, socioeconomic and family characteristics may affect health literacy and eating attitudes.

Conclusions

At the end of the study, nearly half of the adolescents were found to have a problematic-limited and inadequate level of health literacy, whereas most of them were determined to have positive eating attitudes. A weak correlation was found between health literacy levels and eating attitudes of the adolescents. Gender, BMI, meal frequency, and status of applying a diet previously were found to affect the eating attitudes of adolescents. Moreover, it was observed that adolescents had a higher level of health literacy as their ages increased; but they exhibited more negative eating attitudes.

Clinical implications

  • Adolescents could be given educative and promoting trainings (seminars, conferences, etc.) for health literacy.

  • Educative and promoting topics for health literacy could be included in the curriculum.

  • Interdisciplinary studies should be conducted in this field due to the high occurrence of eating attitude disorders among adolescents by considering them as fatal.

  • Adolescents sould be provided an education on regular nutrition by the school nurses in order to enable them to gain healthy dietary habits.