Pythagorean Self-Awareness Intervention Promoted HealthyDietary Patterns, Controlled BodyMass Index, and Reduced Self-Reported Stress Levels of Primary School Children: Α One-Arm Pilot Study

Pythagorean Self-Awareness Intervention Promoted Healthy Dietary Patterns, Controlled Body Mass Index, and Reduced Self-­Reported Stress Levels of Primary School Children: Α One-Arm Pilot Study Marilena Panagiotou, Ioanna Maria Velegraki, Orsalia Gerakini, Flora Bacopoulou, Maria Charalampopoulou, Maya Louvardi, Xanthi Tigani, Aimilia Mantzou, Dimitrios Vlachakis, Christina Kanaka-­ Gantenbein, George P. Chrousos, and Christina Darviri Abstract Stress is common in childhood and an important factor that affects behavior later in adulthood. The aim of this study was to assess the effects of the Pythagorean Self-Awareness Intervention (PSAI), a holistic “cognitive reconstruction” technique to assess primary school children’s stress levels, adherence to the Mediterranean diet, and body mass index. Secondary outcome measures included relations with peers, sleep, and hair cortisol concentrations. This one-arm pilot study took place in a primary school, from February to M. Panagiotou · I. M. Velegraki · O. Gerakini · M. Charalampopoulou · M. Louvardi · X. Tigani · C. Darviri School of Medicine, National and Kapodistrian University of Athens, Athens, Greece F. Bacopoulou (*) Center for Adolescent Medicine and UNESCO Chair in Adolescent Health Care, First Department of June 2019. Participants were 32 pupils attending the second grade of primary school who received the 8-week PSAI to adopt healthy behaviors and lifestyle. Self-report measures were applied for the evaluation of various variables at the beginning and the end of the eight-week intervention. There were statistically significant reductions in stress levels (p = 0.00), nightmares’ frequency (p = 0.00), body mass index (p = 0.03), and bully scale (p = 0.00), and improvement in Mediterranean diet quality (p = 0.00). Hair cortisol concentrations increased (p = 0.02). The social scale significantly increased. Bedtime remained the Pediatrics, School of Medicine, National and Kapodistrian University of Athens, Aghia Sophia Children’s Hospital, Athens, Greece e-mail: fbacopoulou@med.uoa.gr A. Mantzou First Department of Pediatrics, Aghia Sophia Children’s Hospital, Athens, Greece e-mail: amantzou@med.uoa.gr © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 P. Vlamos (ed.), GeNeDis 2022, Advances in Experimental Medicine and Biology 1425, https://doi.org/10.1007/978-3-031-31986-0_2

same after the intervention. This pilot trial showed that the PSAI promoted healthy dietary patterns, controlled children’s body mass index, and reduced their self-reported stress levels. Further research on the implementation of this holistic program on children is suggested, in well-powered randomized controlled trials. Research on stress demonstrates that it can have both beneficial and harmful effects on health, wellbeing, and performance [1]. In fact, stress experienced by children each day can influence a plethora of complex and interacting physiological reactions. These reactions affect many organ systems within the body. For instance, emotional stress can stimulate the autonomic nervous system, mainly the sympathetic branch, and alter heart rhythm patterns, ultimately altering the activity pattern in the afferent neurological information transmitted from the heart to the brain. Matthews, Gump, Block, and Allen [2] also found that children with significant sources of ongoing stress in their lives exhibited increased physiological activation in response to acute laboratory stressors. Negative affect was also found to be linked to increased resting blood pressure levels in adolescents [3]. Similarly, Matthews et al. found that children who had chronic or ongoing stressors present in their lives exhibited higher diastolic blood pressure responses to acute laboratory stress tasks when compared to children with less background stress in their lives. Exposure to chronic and acute life stressors can disrupt the neuroendocrine stress regulation system. The increased production of cortisol can result in epigenetic changes in the structure of regions of the brain responsible for emotion regulation and other important functions, and promote obesogenic eating behavior and dietary patterns, as well as lifestyle factors (e.g., disturbance in daily routine, poor sleep, low physical activity) that may increase obesity risk [4–7]. One step further, it has been reported that overweight or obese children are more likely to experience bullying victimization in school settings across different countries [8]. On the other hand, it has been reported that bullied children exhibit a greater risk of becoming overweight or obese [9], while obesity has been found to be associated with psychosocial maladjustment including increased anxiety, depressive feelings, loneliness, lowered self-esteem, and behavior problems. The above data support the notion that ongoing stress and improper management not only affects a child’s health status in the present but also may have cumulative and long-term effects. In examining the present effects of stress, research has also supported the idea that the presence of stress in children can impair cognitive processes involved in learning [10] as well as appropriate social interactions with others. Parents, on the other hand, may not be able to identify children’s stress and its impact on their children, as it is suggested by Breiner et al. [11], D. Vlachakis Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece e-mail: dimvl@aua.gr G. P. Chrousos University Research Institute of Maternal and Child Health & Precision Medicine, and UNESCO Chair in Adolescent Health Care, National and Kapodistrian University of Athens, Aghia Sophia Children’s Hospital, Athens, Greece Keywords Body mass index · BMI · Intervention · Pythagorean self-awareness · Stress · Healthy lifestyle · Bullying · Children · Students · Mediterranean diet 2.1 Introduction C. Kanaka-Gantenbein First Department of Pediatrics, School of Medicine, National and Kapodistrian University of Athens, Aghia Sophia Children’s Hospital, Athens, Greece e-mail: ckanaka@med.uoa.gr

and it has also been suggested that many parents with peers, sleep, and hair cortisol concentration believe that the child is seeking attention or being (HCC). difficult, rather than recognize their behaviors as a result of stress. School settings with the collaboration of par- 2.2 Subjects and Methods ents, teachers, and health professionals can ideally be used for the implementation of health 2.2.1 Study Design promotion programs to primarily manage stress and prevent its adverse effects on children. A one-arm pilot study took place at the 4th Traditionally, school-based programs for over- Primary School of Chalandri, Municipality of weight and obese children have focused only on Attica Province (Greece), from February to June the training of healthy eating and increase in 2019. The program received ethics approval by physical activity [12]. However, there is a need the Ministry of Education Φ.2.1/ΣΔ/43813/Δ7 for school-based intervention programs to reduce for the academic year 2019–2020. stress and its effects. Multicomponent school-­ based interventions promoting adherence to the Mediterranean diet (MD) have the potential to 2.2.2 Participants combat obesity [13]. Based on the aforementioned, we present the Pupils attending the second grade of primary effects of the Pythagorean Self-Awareness school with good comprehension of the Greek Intervention (PSAI), a novel holistic stress man- language were eligible to participate in the study agement program that combines evidence-based intervention for eight weeks. Children were lifestyle recommendations (Mediterranean diet, excluded from the study if they practiced other sleep routine, physical activity, limited use of stress management techniques. Written consent screens, etc.) and cognitive reconstruction based forms were obtained from children’s parents on the teaching of the ancient Greek philosopher, before inclusion in the study. Pythagoras. The PSAI has demonstrated favorable physical, metabolic, and mental health outcomes in 2.2.3 Measurements children and adults in Greece. In the school setting, Kalogiratou et al. [14] found that PSAI 2.2.3.1 Socio-demographic Data decreased emotional eating and promoted well- Sex, age, family members, and siblings were being in third grade primary school children. recorded for each study participant. Measurements PSAI has also demonstrated amelioration of took place in the classroom after completion of stress and aging biomarkers in a sample of type II school’s schedule. diabetes mellitus and healthy adults [15]. In addiMeasurements were performed by a health tion, the PSAI showed positive results in decrease professional trained in the science of stress. in weight in a sample of obese adults as well as in Children completed the questionnaires on their a community sample [16, 17]. Furthermore, the own in the presence of the stress scientists in case implementation of PSAI had positive outcomes they had any queries. The following measures in a sample of patients with major depression were assessed at baseline and after the [18]. intervention. The primary aim of the study was to investigate the effects of the PSAI on primary school 2.2.3.2 Anthropometric Data students’ stress levels, adherence to the Body weight and height were measured at school Mediterranean diet, and body mass index (BMI). with the use of a calibrated digital scale and a Secondary outcome measures included relations stadiometer, in the minimum clothing possible. Body mass index (BMI) was estimated.

2.2.3.3 Hair Cortisol ized by others, and tend to act in a pro-social or A sample of hair (3 cm) was obtained from each cooperative manner). The instrument has been participant for measurement of hair cortisol con- validated in children and adolescents aged centration (HCC). A lock of hair as thick as a 8–14 years [22]. pencil was cut by scissors from the posterior verSleep: A series of questions were asked to tex as close as possible to the scalp. As hair has a measure the bedtime and the frequency of nightpredictable growth rate of about 1 cm/month, the mares. Mean scores were calculated. closest part of 1 cm to the scalp approaches the production of last month’s cortisol. Hair samples were stored in paper envelops at room tempera- 2.2.4 Pythagorean Self-Awareness ture pending analysis. The first three centimeters Intervention for Children of hair proximal to the scalp were cut and pulverand Adolescents ized with a ball mill. Cortisol was extracted into methanol. Hair cortisol analysis took place at the Pythagorean Self-Awareness Intervention for Choremeio Research Laboratory, Unit of Clinical Children and Adolescents (PSAI-CA) is a ­holistic and Translational Research in Endocrinology of “cognitive reconstruction” technique of stress the First Department of Pediatrics, School of management and improvement in the quality of Medicine, National and Kapodistrian University life, sleep, and memory. The technique was of Athens, Greece. Physiological mean concen- developed by the Medical School of Athens at tration of hair cortisol in healthy children aged National and Kapodistrian University based on eight to nine years has been reported to be 6.7 pg/ the new concept of Evidence-Based Lifestyle mg [19]. Medicine [23] and World Health Organization Stress in Children Questionnaire (SIC): The (WHO) data for adolescents [9]. The technique Stress in Children Questionnaire consists of 21 relied on the philosophy of an ancient Greek phiquestions that examine the stress that children losopher Pythagoras of Samos (c. 570 e c. 495 may encounter in many aspects of their life and BCE) [24]. As Pythagoras stated, self-awareness has been used with children aged between 8 and and eudemonia are achieved through constant 12 years. Higher scores indicate higher levels of introspection and self-control. The purpose of the stress [20]. technique is to increase self-awareness using a KIDMED Index: The Mediterranean Diet moral reference for this critical appraisal. The Quality Index for Children and Adolescents analysis of the neurophysiology of the technique (KIDMED) is based on the principles of refers to the activation of the Default Mode Mediterranean dietary patterns and comprises 16 Network (DMN), a large-scale functional brain “yes” or “no” questions that could be self-­ network. The DMN is activated when the indiadministered or conducted by interview. Overall vidual focuses on internal self-relevant mental score ranges from 0 to 12 and it is derived from processes such as memory retrieval of autobiothe summation of the values, which is classified graphical events, envisioning future actions, and into three levels: (1) >8, optimal adherence to being aware of the perspectives of others [25, Mediterranean Diet; (2) 4–7, improvement 26]. needed to adjust intake to Mediterranean patThe technique of PSAI-CA is mainly practerns; and (3) ≤3, very low diet quality. The ticed shortly before night sleep and the individual instrument has been used in children and adoles- must follow three cognitive processes. A rule cents aged 3–18 years [21]. referred to “The Twelve Virtues” has been develPeer Relation Questionnaire for Children oped as a moral reference to accomplish the chil(PRQ): The Peer Relation Questionnaire (short dren’s self-awareness by following five simple form) for children measures the bullying phe- steps, which are presented in Table 2.1. nomenon consisting of 12 items with 3 subscales Pythagorean virtues are: (1) fairness, (2) truthful(tendency to bully others, tendency to be victim- ness, (3) charity and spirituality, (4) decent

behavior, (5) discipline and respect for the law, (6) order and accuracy, (7) industriousness, (8) cooperation, (9) contribution to the general good, (10) courage, (11) cleanliness and perfect appearance, and (12) temperance. Events or choices of personal relationships are judged freely by the individual since the primary goal is to enhance self-awareness and not to criticize them [27]. that might have emerged during the previous days. In each session, a weekly activity logbook (self-report measure of compliance to the PSAI), reading materials, and homework assignments were provided. 2.2.4.1 PSAI-CA Implementation Eight sessions were part of the program and numerous pieces of advice were included about healthy nutrition, sleep, physical activity, bullying, and screens (mobile-tablet-PC). Sessions were held once per week (90 min) over eight weeks. The first session included information about the stress system, symptoms, and effects. Students were trained individually in diaphragm breathing using the Biofeedback software. The five tricks were presented to the students. Pedometers were provided as a motivation for exercising. In the second session, participants received instructions on the practice of Pythagorean Self-Awareness and the 12 virtues were taught. In the following sessions guidelines and advice on the Mediterranean diet, physical activity, sleep, use of screens, and bullying were given to the students. During sessions, they were encouraged to discuss practical issues or ideas The data were analyzed by non-parametric tests due to the small study sample. Adjusted means were calculated through paired sample t-test. The level of significance was set at 0.05. BMI was calculated as the ratio of body weight to the square of height (kg/m2). BMI z-scores were ­calculated based on World Health Organization (WHO) growth charts. The SPSS statistical software version 22.0 for Windows was used to perform statistical analyses (SPSS Inc., Chicago, IL). The sample size was not calculated prior to the intervention. However, post-hoc power analysis was performed. Power exceeded 90% based on calculations performed in R software using the pwr package [28]. Table 2.1 The five steps of PSAI-CA applied daily for 30 minutes by each participant 1st 2nd 3rd 4th 5th Before night sleep sitting on a chair, breathe diaphragmatically for 10 min Read the 12 virtues then turn your attention inwards and assume the role of the observer Recall every event of the day in the exact time sequence it happened Observe your day like a video timeline Choose the events that seem important to you and assess your actions (reward, detest) using 3 questions based on the 12 virtues and the instructions for a healthy lifestyle you were taught:   What have I done right?   What have I done wrong?   What have I omitted that I ought to have done? The next day make a quick review of the previous day and set your new goals 2.2.5 Statistical Methods 2.3 Results A total of 32 pupils participated in the study and there was one dropout due to change of school. The flowchart of study participants is depicted in Fig. 2.1. Full participation in all sessions and full compliance with PSAI were assessed in the weekly diaries. The mean age of the participants was 8 years, with 53.1% of participants being girls, 46.9% boys, and 84.4% had siblings, while most of the participants’ families had 4 members. Finally, BMI z-scores of the participants were within normal range. Descriptive statistics are presented in Table 2.2. Table 2.3, presents the study’s results. There was a statistically significant reduction in stress levels (SIC, p = 0.00), nightmares (p = 0.00), BMI z-scores (p = 0.02), and HCC (p = 0.02). Adherence to Mediterranean diet was also found to have statistical improvement; KIDMED (p = 0.00) was also improved after

Fig. 2.1 Flowchart of the study participants Table 2.2 Baseline socio-demographic and anthropometric characteristics of study’s participants Referential measurements Sex  Boys  Girls Mean age in years (SD) Min-max age range in years Siblings  Yes  No Family members  3  4  5+ Anthropometric measures  Median weight in kilograms (iqr)  Mean height in cm (SD)  BMI z-score Descriptive statistics of the study’s participants N = 32 15 (46.9%) 17 (53.1%) 8.03 (0.18) 8–9 27 (84.4%) 5 (15.6%) 3 (9.4%) 25 (78.1%) 4 (12.5%) 26.90 (6.05) 1.24 (0.06) 0.94 ± 0.64 BMI body mass index, iqr interquartile range, SD standard deviation the intervention program. Hair cortisol concentrations statistically increased (HCC, p = 0.02). Statistical decrease was also noticed in the Bully scale of the bullying questionnaire (PRQ-Bully, p = 0.00) while the social scale was statistically increased (PRQ-Presocial, p = 0.00). No statistically significant changes were observed in the PRQ-­ Victim scale (p = 0.11) and bedtime (p = 0.82).

Table 2.3 Baseline and post-intervention measurements of the study participants Measurements Primary outcomes SIC KIDMED BMI z-scores Secondary outcomes Bedtime Nightmares PRQ-Bully PRQ-Presocial PRQ-Victim HCC Pre-intervention N = 32 Post-intervention N = 32 p-Value 2.29 ± 0.70 6.41 ± 1.87 0.94 ± 0.64 1.40 ± 0.49 10.61 ± 1.39 0.60 ± 0.81 <0.001* <0.001* <0.05 21.03 ± 1.75 1.33 ± 1.16 8.15 ± 2.55 12.6 ± 1.96 8.45 ± 2.31 4.22 ± 1.98 21.30 ± 0.54 0.52 ± 0.90 8 ± 2.62 13.81 ± 2.03 7.42 ± 1.62 5.68 ± 3.18 0.82 <0.001 <0.001 <0.001 0.11 <0.05 SIC Stress in Children Questionnaire, KIDMED Mediterranean Diet Quality Index for Children and Adolescents, PRQ Peer Relations Questionnaire for Children, HCC Hair Cortisol Concentrations, BMI Body Mass Index Measurements are presented in mean ± standard deviation. *Level of significance: p < 0.05 2.4 Discussion eating and psychological state [14]. In recent studies, the Mediterranean diet had a beneficial The study aimed to assess the effectiveness of a effect on certain body systems [33–35]. Children novel holistic cognitive stress management pro- and adolescents may be the age groups with the gram, PSAI-CA, which included consults of most unfavorable Mediterranean diet profile [36]. stress, quality of life, sleep, eating behavior, and The PSAI has also been used in overweight/ bullying behavior of children. The hypothesis obese adults as an effective method for reduction that PSAI-CA is effective to reduce stress and in BMI, body fat, emotional and external eating adopt a healthy lifestyle has been confirmed. behavior, as well as adverse metabolic indices After the intervention program, stress levels, [16]. nightmares, and BMI were statistically reduced. The main reason behind bullying’s reduction In the bullying scale, the bully, which represents is the full compliance of children with PSAI, an the physical and psychological maltreatment of item of which was the Pythagorean Virtues. one child from another, was diminished. The While finding more ways to cooperate, children social scale was increased as well as hair cortisol managed to decrease conflicts. Anger’s control concentration. Bedtime and PRQ-Victim scale was managed through the virtue of temperance. were still the same after the intervention Instead of counting on conflicts, they solved their program. disputes through dialogue and mutual underThe reduction in stress levels can be explained standing. Many anti-bullying programs are effecby the fact that the participants were able to con- tive, because intervention programs reduced peer trol any stressful factor applying the PSAI tech- victimization and increased school safety in 14 nique. The program reduced stress levels and schools [34, 37, 38]. Therefore, anti-bullying negative emotions and favored a less reward-­ programs appeared to be substantial in encouragseeking behavior (e.g., recreational habits) and ing children to change their behavior for the betmore healthy choices daily [29–32]. Study par- ter [39, 40]. ticipants changed their BMI because of the nutriAs per the study’s results, the social scale was tion guidelines based on the Mediterranean diet, increased, which means that peer relations were which is considered one of the healthiest dietary improved among children. Social skills were also models. Kalogiratou et al. found that the imple- improved by supporting each other. The relationmentation of the PSAI had positive effects on a ships between them ameliorated and they became sample of primary school attendants’ emotional more cooperative.

The elementary students who suffered con- training, they reported lower stress [48] and posistant nightmares have reported a decrease in tive results [49]. Furthermore, intervention prothem. Even though our sample was not obese, grams showed that BMI had a significant this finding is similar to the study of Mazurak beneficial alteration [50–53]. A meta-analysis of et al. [41] who compared sleep quality of chil- 19 studies (total participants = 4063) of educadren and adolescents with obesity versus a tional interventions in children and adolescents healthy sample and suggested that sleep hygiene evaluating social–emotional training, relaxation education, as part of weight-loss therapy, may programs, problem-solving, and stress manageprovide both physical and psychological benefits ment showed a positive effect on reducing the to this population. The effectiveness of the PSAI symptoms of stress and strengthening coping has been confirmed by the reduction in anxiety skills [54]. Environmental, cognitive, and behavand an improvement in sleep, diet, and exercise ioral factors work together to influence children’s [42]. knowledge of nutrition, self-efficacy, and healthy Our results are consistent with cognitive behavior choices. Both have been shown to conbehavioural therapy (CBT) studies that also tribute to children’s eating behavior [36]. improved sleep and reduced insomnia [43–45]. However, this study faces some limitations Cortisol is a measure of stress as an end-­ including small and random sample size, lack of product of the hypothalamic-pituitary-adrenal control group and short follow-up, small duration (HPA) axis. Hair cortisol is considered superior of the intervention, and lack of other age groups. to the serum and urine cortisol for the evaluation Furthermore, compliance to the intervention was of chronic stress, as it reflects cortisol aggrega- assessed by children’s self-reports without parention over the previous months. Hair cortisol has tal reassurance that all recommendations were been associated with physical and mental ill- followed. Thus, the results of the study cannot be nesses in children and adolescents [46]. In our generalized. study hair cortisol concentrations were increased, which could indicate the activation of HPA axis [47]. This could be explained by increasing atten- 2.5 Conclusions tion and emotional effort through cognitive reappraisal [29]. The frontal lobe can be activated via This pilot study showed that the PSAI-CA gnostic reconstruction. The technique was effec- reduced stress levels and established healthy tive using the moral reference and critical behaviors and lifestyle in a sample of second appraisal whereas most intervention programs grade primary school students. Further research use a specific technique. Pupils embraced the 12 on the implementation of the PSAI on school virtues and learned how to evaluate themselves, children is needed to verify these findings, discerning what is right and what is wrong. They through a well-powered randomized controlled acquired self-control, self-discipline, and trial. restraint. The role of the observer gives the possibility of self-review and self-evaluation [30]. Acknowledgments We thank all students for participatThe children were equipped with skills such as ing in the study, as well as the headmaster, Mrs. Bassia self-discipline and self-control and are now capa- Athena Spyridoula, and the teachers Mrs. Petropoulou Petroula and Mrs. Argyri Eleni of the 4th Primary School ble of using them for their benefit on their way to of Chalandri, Municipality of Attica, Greece. development. Those skills will also assist them in spiritual improvement, academic performance, and wellness, which in turn lead to social wellbe- References ing [32]. Besides that, to reduce stress and obesity 1. Crum AJ, Jamieson JP, Akinola M (2020) Optimizing stress: an integrated intervention for regulating stress mindfulness interventions have been impleresponses. Emotion 20(1):120 mented. When children received mindfulness

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