MATERIALS AND METHODS

Design, place and time: The study was performed between October 2017 and May 2018 with 400 adults who could communicate clearly, who lived in Ankara or Konya in Turkey, who were between 18 and 64 years old, who voluntarily agreed to participate in the study and who reported eating breakfast regularly (at least 4-5 days a week).The participants who met the inclusion criteria were contacted during the study period. According to the sample size in this period (n = 400), the power of the study was determined to be 0.95 using the G-Power 3.1 program (Universität Dusseldorf, Germany) based on a 0.05 significance level and a 0.2 effect size.

Sociodemographic characteristics of the participants (age, sex, educational status, marital status), a scale of the level of adherence to the Mediterranean diet and breakfast consumption records from the day of data collection were collected by the researchers with a questionnaire form using the face to face interview method.

Body weight (kg) was measured using a portable digital scale and height (cm) was measured and recorded using a nonflexible tape measure and these were the anthropometric measurements. Body mass index (BMI: body weight kg height^–2 m²) was calculated from body weight and height measurements and was categorized as follows: <18.5 kg m^–2 underweight, 18.5-24.9 kg m^–2 normal and ≥25.0 kg m^–2 overweight or obese.

Ethical aspects of the study: This study was performed in accordance with the principles of the Declaration of Helsinki. Ethics Committee Approval (Decision No. 10/170 dated 29.05.2017) was obtained from the Ethics Committee of the Rectorate of Ankara University. Informed consent was obtained from each individual who agreed to participate in the study.

Prevention with mediterranean diet (PREDIMED): The PREDIMED scale was applied to the participants and consists of 14 questions. The answers were scored by giving “+1 points” for each “yes” and “0 points” for each “no”. After collecting all data, a PREDIMED score of 5 or less was considered “low compliance”, a PREDIMED score of 6-9 was considered “moderate compliance” and a PREDIMED score of 10 and more was considered “high compliance¹⁴.

Statistical analysis: Data obtained from the research were analyzed using the SPSS package program (IBM SPSS Statistics 23.0. Armonk, NY, USA: IBM Corp; 2013) and the data of food consumption records were transferred into the SPSS program after being processed using the BEBIS program [The German Food Code and Nutrient Data Base (BLS II.3, 1999)].

The mean (), standard deviation (SD) and lower and upper values were calculated for quantitative data. Quantitative data are shown in number percent tables. The chi-square test (Pearson chi-square) was used to compare categorical variables. One-Way ANOVA (post hoc Tukey’s test) was used to compare the means between more than two independent groups. The results were considered statistically significant at p<0.05.

RESULTS

A total of 400 adult individuals (63 males (15.7%) and 337 females (84.3%)) with a mean age of 34.0±13.5 years participated in the study. Having evaluated the levels of adherence to the Mediterranean diet, it was found that more than half (60.3%) of the participants had moderate compliance.

As the age of the adults participating in the study increased, compliance with the Mediterranean diet increased (p<0.001). Similarly, marital status was found to have a significant impact on compliance with the Mediterranean diet (p<0.001) Table 1.

Table 1:	The Distribution of sociodemographic characteristics of participants according to adherence to the mediterranean diet
*p<0.05, Chi-square test, **One-way ANOVA test, BMI: Body mass index abcStatistically significant difference between application

Table 2:	The consumption of food at breakfast of participants according to adherence to the mediterranean diet
*p<0.05, One-way ANOVA test, abcStatistically significant difference between application

Table 3:	Evaluation of energy and macro nutrient intakes of participants in breakfast according to adherence to the mediterranean diet
*p<0.05, One-way ANOVA test

Regarding the data obtained in relation to the nutrient consumption frequency of individuals (Table 2), it was observed that those who showed high compliance with the Mediterranean diet were more likely to have consumed soup and oilseeds (walnut, hazelnut, peanut, almond) at breakfast than individuals with low or medium compliance (p<0.001). In addition, the consumption of herbal tea varieties at breakfast was lower in those with low compliance (9.1±29.5 mL) than in those with moderate or high compliance (p<0.001). Carbonated drinks were never consumed by individuals with high adherence.

The total energy and macronutrient contents of the food consumed by the participants at breakfast in one day were examined and the results are shown in Table 3. According to the levels of adherence to the Mediterranean diet, the average energy, carbohydrate, protein, fat and fatty acid intakes of individuals at breakfast were similar (p>0.05).

DISCUSSION

The Mediterranean diet, which is accepted as a healthy diet form, has been studied for many years and it has been determined that it is protective against many chronic diseases, positively affects cognitive capacity and increases quality of life^15,16. One of the important components of a healthy diet is the regular consumption of breakfast¹⁷. In this study, we attempted to determine how the adherence of adult individuals to a Mediterranean diet affects breakfast consumption in terms of energy and nutrient intake.

In the study conducted by Hu et al.¹⁸ to evaluate the relationship between compliance with the Mediterranean diet and some factors, it was found that nonsmokers, those who performed physical activity and individuals with high educational levels showed high compliance with the Mediterranean diet but compliance with the Mediterranean diet was low in obese and single individuals¹⁸. It was also observed that older males followed the Mediterranean diet more than younger males¹⁸. Similarly, in this study, it was found that compliance with the Mediterranean diet was lower in single participants and that diet compliance increased significantly with age (p<0.05) (Table 1).

The daily consumption of vegetables and fruits, which are an important component in the Mediterranean diet, is 2-3 servings for vegetables and 4-6 servings for fruits^5,19.The antioxidant, vitamin, mineral and flavonoid contents of fruits and vegetables have anti-inflammatory properties and thus have protective effects against many chronic diseases². In this study, it was determined that the consumption of fruit, freshly squeezed fruit juice and vegetables at breakfast was higher in the group with moderate or high compliance with the Mediterranean diet (p>0.05). In addition, herbal tea consumption at breakfast was higher in the same two groups (p<0.05) (Table 2). However, the average amount of fruit, freshly squeezed juice and vegetables consumed by the participants at breakfast was quite low. Although, only the breakfast meal was evaluated, it was difficult for the participants to consume the total amount of vegetables and fruits recommended in the Mediterranean diet for the rest of the day. In addition, the fact that the habit of consuming fruit and vegetables at breakfast is culturally uncommon may have affected this outcome.

Oilseeds are rich in monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) and are an important component of the Mediterranean diet. Consumption of a handful of oilseeds is recommended each day⁵ and oilseeds may have an effect on reducing cardiovascular risk, improving lipid profile and triglyceride levels and reducing the inflammatory response in patients with hypercholesterolemia²⁰. In this study, it was determined that the consumption of oilseeds, such as walnut, hazelnut, peanut and almond, was the highest in the group that had high adherence to the Mediterranean diet (p<0.05). In addition, the mono- and polyunsaturated fatty acid intake of the participants in the high adherence group was higher than that in the other two groups (Table 2). Excessive consumption of oilseeds may have contributed to this difference.

The traditional Mediterranean diet recommends eating one or two portions of cereals at meals in the form of bread, pasta, rice, couscous or other cereals. In particular, due to processing, magnesium, phosphorus, iron and vitamins can be lost from foods in the grain group, so the foods in the grain group must be unprocessed⁵. The health effects of whole grains have been associated with their being rich in vitamins, minerals, dietary fiber components (inulin, lignin, beta glucan, etc.), phytosterol and numerous phytochemicals²¹. In this study, it was determined that the consumption of white bread, pastries, bagels and donuts was higher in all groups than the consumption of whole grain bread at breakfast (Table 2). This may result in lower intake of the above mentioned health-contributing nutrients, thereby increasing the risk of nutrition-related diseases.

The recommended foods for breakfast in the Mediterranean diet are oatmeal, fresh fruit, whole grain bread, low-fat yogurt and boiled eggs 3-4 times a week²².

In a sample Mediterranean diet breakfast, it was suggested to consume 3/4 cup of fresh fruit and 1/4 cup of walnuts with 1 cup of yogurt, 1/4 cup of avocado butter, 2 teaspoons of natural butter, 1 slice of whole grain bread and coffee or tea²³. Another suggestion for a Mediterranean diet breakfast is muesli, avocado, bananas, almonds, apricots, whole grain toast, hazelnut butter, boiled eggs and a dried fruit and cereal mix (granola)²⁴.

Considering the importance of breakfast, it is understood that the foods consumed at breakfast are also important in relation to compliance with the Mediterranean diet. However, studies with larger samples in which more detailed food groups are examined will raise awareness on the subject. For this reason, this study is a pioneer for future studies.

CONCLUSION

Based on this study, consuming a small amount of fruits and vegetables at breakfast, which is the most important meal of the day and consuming more cereal products prepared with refined flour, reduces compliance with the Mediterranean diet. Moreover, when the participants were generally considered, the number of people who had moderate or high compliance with the Mediterranean diet was low. Although, this study reflects the foods consumed only at breakfast in relation to adherence to the Mediterranean diet, the participants' choice of food and beverages guided us to assess their compliance. Furthermore, recent studies have indicated that there is no single Mediterranean diet model. According to the general principles of the Mediterranean diet, the pattern of the diet may change according to cultural characteristics. The most important meal of the day is breakfast, which can be characterized by the positive or negative effects of the foods consumed. For this reason, it is advisable to distribute the nutrients contained in the Mediterranean diet throughout each meal in a balanced manner and to consume a Mediterranean diet at breakfast.

SIGNIFICANCE STATEMENT

The adherence to the Mediterranean diet was not significantly different between the body mass index groups. Further studies that include other anthropometric measurements and body analyses are needed.

ACKNOWLEDGMENTS

We thank nutritionists Büşra Özyalçın and Ebrar Biçer for their contributions and help with data collection.