Nutritional status and related factors on academic achievement of adolescents in high schools in the Hlaing Tharyar township, Yangon, Myanmar

BACKGROUND/OBJECTIVES: Chronic malnutrition in adolescents may result in signi�cant academic di�culties at school. This study aimed to determine the impact of nutritional status and related factors on the academic achievement of adolescents in secondary/high schools in Myanmar. SUBJECTS/METHODS: A cross-sectional survey was performed in two high schools in Hlaing Tharyar District, Yangon using a self-administered questionnaire on food intake and other factors potentially affecting nutritional status. Grade-point averages (GPA) in the previous academic year were recorded to identify any association between nutritional status and academic achievement.


Introduction
Adolescence is a transition period involving substantial physical, psychological, and cognitive growth [1].
Many adolescents engaged in school activities are challenged by limitations in their cognitive abilities.To enhance the physical and intellectual abilities of adolescents, they should be provided with the appropriate quantity and quality of nourishment [2].Adolescents who are either over-or underweight have signi cant di culties in school, both academically and socially [3].This implies that the nutritional status of adolescents can in uence academic achievement.
A large number of adolescents suffer from chronic malnutrition.The prevalence of protein-energy malnutrition is high in almost every country in the region [4].World Food Programme (WFP) stated that Myanmar is still one of the Southeast Asian countries with the highest undernutrition rates [5].
Academic achievement is the outcome or performance of education that indicates the extent to which a student has accomplished speci c goals that were the focus of activities in instructional environments [6].To evaluate if students are gaining su cient academic knowledge, the teachers are required not only to assess the students' knowledge but eventually also to summarise this assessment into the form of a letter or number [7].Some educators have recommended that grades should only re ect the students' competencies in a given subject.Grading students in terms of what they know will help teachers to provide information to students and parents with speci c feedback on which learning areas call for improvement [8].A recent study demonstrated that grades re ect learning goals which are part of academic performance [9].
Proper nutrition is one of the most important requirements for academic achievement.If students do not receive appropriate nutrition, they can become underweight or overweight and suffer from various nutrient de ciencies that can affect their academic achievements.Some studies found that low anthropometric measurements are frequently associated with poor academic achievement [10].A previous study in India showed that the student populations with the lowest prevalence of stunting achieved the highest grades [11].A study in Thailand showed that being or becoming overweight during adolescence was signi cantly associated with poor academic achievement [12].A study in India stated that students who received normal nutrition were about three times more likely to receive the best grades ('A+' or 'A') compared with students suffering from stunting [13].
Many factors may in uence the nutritional status of adolescent students; habits of food choices, the amount of food intake, eating behaviour, lack of knowledge about nutrition, food availability, the quest for independence and acceptance by peers, socioeconomic status of the student's family, and physical activity affect the nutritional status of students [2].Students consuming a balanced, nutrient-dense diet perform better in areas of participation, social behaviour, attendance, and getting their assigned tasks done more completely than those who do not eat well [3].These are some of the reasons why the nutritional status of students is important for their academic achievement.
Although a number of factors such as intelligence quotient, emotional quotient and perseverance play a signi cant role in determining a child's academic achievement, nutritional status is one of the main factors potentially impacting on academic achievement.Therefore, this study aimed to determine the impact of nutritional status and related factors on academic achievement of adolescents in high schools in Hlaing Tharyar Township, Yangon, Myanmar.

Study design
This cross-sectional study was carried out to identify the association between nutritional status and related factors on academic achievement of adolescents in high schools, Hlaing Tharyar Township, Yangon, Myanmar.Two schools, namely No. (1) and No. (2) Basic Education High Schools (B.E.H.S), Hlaing Tharyar, were selected in the Northern district of the Yangon metropolitan area.Questionnaires (Supplement 1.) were developed and prepared with a code system for each participant and each school.After understanding the objectives of the study explained by the researcher, the participants were asked to sign the consent form before the measurement of their body mass indexes (BMIs) and before responding to the questionnaires.Each participant had the right to cancel the consent and withdraw from the study at any time if the participant did not wish to continue.

Inclusion criteria
Secondary school students aged 13-17 years who were willing to participate in this study and able to provide the consent form signed by their parents or guardian were invited.

Exclusion criteria
We excluded students who did not function well enough to respond relevantly to the questionnaires, who were severely ill and/or absent, or who did not receive approval from their parents or guardian.

Data collection
This study was performed in May 2017 and was based on three components of anthropometric measurements, academic grades and information provided through self-administered questionnaires.
During data collection, regular and closed supervision were performed with the help of school teachers to control possible bias.

Anthropometric measurements
Height and weight for all participants were measured using standard anthropometric methods and used to calculate the BMI according to the World Health Organization's growth reference for individuals aged 5-19 years, (http://www.who.int/growthref/en/).The hip at the widest length of the buttock and the waist circumference at a level midway between the lower rib margin and the iliac crest of the participants were measured using measuring tape, and the data were used to calculate the waist-hip ratio [14].

Recording academic grades
Previous year academic grades were retrieved from the Comprehensive Personal Record of each participant.Grade point averages (GPA) were used to re ect academic grades in the two high schools for the 2016-17 academic year.The GPA-based classi cation of A, B, C, and D corresponded to 80-100%, 60-79%, 40-59%, and <40%, respectively.

Self-administered questionnaires
Questionnaires included four sections regarding demographic information, food intake, and factors relating to adolescent nutritional status (knowledge and attitude toward food intake and eating behaviour, physical activity and socioeconomic status of the family).

Food intake survey
Food frequency questionnaires (FFQs) were applied based on the Asian Food Guide Pyramid to assess the food intake by participants.After the investigator team explained the purpose of this study, all participants were requested to complete their FFQ for a period of 30 days.

Participant knowledge on nutritional status
The questions were developed to test the participants' knowledge on food intake, food choices and malnutrition, and there was one correct answer for each question.The questions were developed to address the Go, Glow and Grow food groups currently de ned by the Department of Educational Planning and Training-Ministry of Education and the United Nations Children's Fund.The highest possible total score was 9, and answers were categorised into 'poor level' if the score ranged between 1 and 5, and 'good level' if the score ranged between 6 and 9.

Participant attitude to nutritional status
Questions on food intake and food choices were posed to determine the participants' attitude toward food consumption.The participants showed their degree of agreement by choosing only one answer for each item.Each statement had ve-point numerical scales, ranging from strongly agree, agree, neutral, disagree and strongly disagree.The maximum total score for attitude was 25 and categorised into 'fair attitude' if the score range was 0-16, and 'good attitude', if the score range was 17-25.

Eating behaviour, physical activity, and socioeconomic factors of the participants
Items pertaining to eating behaviour, physical activity and socioeconomic factors of the participants were surveyed and expressed by two-way tables.

Data analysis
The quantitative data of BMI, waist-hip ratio, grade record, FFQ, knowledge, attitude, behaviour, physical activity and socioeconomic status were analysed by using Statistical Package for the Social Sciences programme version 18.0.Descriptive data were presented as numbers, percentages and means with standard deviations.Pearson's χ 2 test was used to determine the association between the nutritionrelated factors of food intake knowledge, attitude and behaviour, physical activity and socioeconomic status on academic achievement of adolescents.

Ethical considerations
The study was approved by the ethics committee of the Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand (MUTM 2017-031-01 issued on July 2017).Data collection was conducted only after obtaining informed consent from the participants.All data was collected con dentially at each stage of data handling.

General characteristics, anthropometric assessments, and grade point average
The sample size of the study was 301 participants from two high schools in Hlaing Tharyar Township.Most participants were female (65.1%).A total of 132 participants (43.9%) were from No. ( 1).

Food intake
Data on the food intake of the participants over the past 30 days was recorded by the FFQ, collated and presented in Table 2. Poultry (42.25%) and sh (36.5%) were the meat items consumed most frequently.Participants consumed milk/yogurt (26.9%) and ground nuts (29.9%) as a protein source as well.

Nutritional status-related factors
There was a statistically signi cant association between the number of meals per day and the nutritional status (p = 0.045).Respondents who had ≤2 meals per day were more likely to have abnormal BMI than those who had ≥3 meals per day (odds ratio [OR] = 1.663, 95% con dence interval [CI]: 1.010-2.739)(Table 3).In addition, although not signi cant, respondents who categorised into fair attitude toward food intake tended to have a less normal nutritional status than respondents who rated as having a good attitude.Up to 82.6% of those who did not walk or who walked for less than 15 minutes had abnormal BMI.Almost 27% of the respondents with abnormal BMI were from families with ≥7 family members, and 42.4% of the respondents' parents were either dead or divorced.

Factors related to academic achievement
Nutritional status and academic achievement Underweight participants were 1.96 times more likely to receive fair grades (C, D) than those who were normal-weight (p = 0.030, OR = 1.960, 95% CI: 1.063-3.614).However, there was no association between overweight/obesity and academic achievement (Figure 1).

Eating behaviour, physical activity, and academic achievement
A statistically signi cant association between the number of meals per day and academic achievement was observed (p = 0.025; Figure 2).Participants who had ≤2 meals per day were 1.886 times more likely to have a 'fair' GPA rating than those who had ≥3 meals per day (OR = 1.886, 95% CI: 1.076-3.306).Nearly 62% of the participants who skipped a meal were scored as 'fair' in the GPA, while only 38.3% of those who did not skip meal were scored as 'fair' in the GPA.No association was identi ed between physical activity and academic achievement.
Meanwhile, there was a statistically signi cant association between the duration of watching or playing games and academic achievement (p = 0.013).Participants who watched and played games for ≥2 hours were more likely to be categorised as 'fair' in the GPA compared with those who did not watch and play games or who watched and played games for <2 hours (OR = 2.002, 95% CI: 1.154-3.474).
Our study also revealed a statistically signi cant association between the duration of walk to school and academic achievement (p = 0.005).Participants who walked for ≥15 minutes to school were 2.499 times more likely to receive a 'fair' GPA than those who did not walk and who walked <15 minutes (OR = 2.499, 95% CI: 1.306-4.782).

Socioeconomic factors and academic achievement
There was an association the father's (p = 0.047) and mother's (p = 0.002) education and academic achievement of the participant.Participants whose fathers or mother had less or just primary education level were more likely to receive a 'fair' GPA compared with those whose father or mother had at least or more than middle or higher education level (OR = 1.752, 95% CI: 1.003-3.061and OR = 2.405, 95% CI: 1.367-4.230,respectively).
A clear association between family income and academic achievement was observed (p < 0.001).
Participants whose family had an income of <2 lakh kyats were 3.017 times more likely to receive a 'fair' GPA than those whose family had an income of ≥2 lakh kyats (OR = 3.017, 95% CI: 1.659-5.486).There was also a clear association between the parents' marital status and academic achievement (p = 0.001); participants whose parents were either dead or divorced were more likely to receive a 'fair' GPA than those whose parents were alive and in a relationship (OR = 2.462, 95% CI: 1.416-4.281)(Figure 3).

Discussion
This study investigated factors related to the nutritional status of adolescents in two basic education high schools in Hlaing Tharyar in the Yangon metropolitan area of Myanmar.There was no association between demographic factors (gender, age, waist-hip ratio, schools) and nutritional status.Regarding the intake frequency of food items, we showed that chicken was the most commonly consumed food item, followed by sh, vegetables and soft drinks.Meat, eggs, dairy products, fruits, and nuts were less frequently consumed (Table 2).Respondents from this study ate various types of food items.However, a balanced diet is critical to intellectual and physical development [15].According to our observations, the participants' energy requirements were in some cases not met by their daily diet.A previous study found that adolescents who do not have a balanced diet may exhibit various degrees of malnutrition with implication on both health and academic development [2].
A study of knowledge on nutrition, attitude toward nutrition and nutritional practices are critical to understanding the development of a community.This study did not nd any association between the level of nutrition knowledge and attitude and nutritional status.Surprisingly, respondents who had a good level of knowledge presented abnormal BMIs, up to 95.7%.However, only up to 73.9% of the respondents who had a fair attitude toward nutrition had abnormal BMIs.When looking further into the eating behaviour, more than 60% of the respondents who had ≤2 meals per day were more likely to have abnormal BMIs than those who had ≥3 meals per day (39.1%,Table 3).A reasonable frequency of meals is important to secure a steady energy distribution throughout the day, especially for adolescents [16].A previous study found that those with the lowest meal frequency had the lowest energy intake but higher fat mass [17].An inverse relationship between meal frequency and overweight and obesity in adolescents has been identi ed [18].Another study found that increasing the meal frequency may be conducive to reducing BMI [19].
Many studies have found an association between physical activity and nutritional status [20][21][22].
Although walking to school was the most common physical activity performed by the participants, our study failed to nd any association between physical activity and nutritional status.
Thus, in this study, eating lower than three meals per day appeared to be the strongest in uencing factor with regard to abnormal nutritional status.However, a good level of knowledge and attitude toward food intake and consuming a healthy and proper diet are still important to ensuring a normal nutritional status.
There was no association between skipping a meal, skipping breakfast or eating a snack and nutritional status.However, we revealed that more than half of the participants (54.8%) skipped a meal on a daily basis.The main reasons provided for skipping a meal was 'not enough time to have a meal' (30.6%), 'did not like the food available' (16.9%), and 'having the habit of skipping a meal' (9.6%).In addition, 8.0% of the respondents skipped a meal when they were in a particularly emotional state (happy, sad, excited, anxious, etc.) and 2.7% also skipped a meal to keep weight.Almost 40% of the respondents skipped breakfast, and 96.7% would eat a snack during the day.A habit of skipping meals could lead to important nutrient de ciencies.Moreover, the habit of eating snacks could result in raised calorie and fat intake.These eating behaviours could affect nutritional status and health [23] (S2 Fig) .The ndings from this study might be bene cial for implementing intervention strategies that could reduce skipping meals and provide healthy snacks to adolescents.
This study identi ed no association between socioeconomic factors and nutritional status.This nding was inconsistent with previous ndings [24][25][26].This might be explained by the low cost of living that allow for the purchase of healthy foods.
We identi ed a statistically signi cant association between nutritional status and academic achievement.
Respondents who were underweight were more likely to receive grades C and D compared with those who had normal weight (p = 0.030) (S1 Fig) .Previous studies have reported that low anthropometric measurements are frequently associated with poor academic achievement [10,27,28].This might be because underweight students may have various nutrient de ciencies which may affect their academic achievements.The study of the Lambani school children in India showed that the majority of students in the 'normal nutrition' category received A+, A, and B+ grades, while more than half of those who were stunted received B and C grades, and none of those categorised as 'stunted' or 'wasted' received A+ or A grades [13].Meanwhile, in our study, there was no relationship between overweight or obesity and academic achievement.This nding was different from that of a previous study carried out in Thailand, which mentioned that overweight students were more likely to have low GPA compared with normalweight students [12].
Our study statistically found the association between the number of meals consumed per day and academic achievement (p = 0.025).Respondents who had ≤2 meals per day were more prone to receive a 'fair' GPA than those who had ≥3 meals per day (Figure 2).We speculate that inadequate nutrition could cause low energy levels among those affected, and the lack of ability to concentrate would be re ected in the low scores on their tests.This was consistent with a previous study reporting that students who did not eat well performed worse in the areas of participation, social behaviour, attendance, and ability to complete assigned tasks compare with those who ate well3.One study stated that the academic achievement of adolescents is associated with a daily intake of three regular meals [29].
Another study found that children with a lower dietary intake had lower academic achievements than those with adequate dietary intakes [30].
We found an association between the duration of walk to school and academic achievement (p = 0.005).
Respondents who walked ≥15 minutes to school were more likely to receive a 'fair' GPA than those who did not walk or who walked <15 minutes (Figure 2).This nding might be explained by the possibility that a long walking distance to school makes students tired after reaching the school and renders them lagging behind in the classroom and private studies.This nding was consistent with a previous study [31] that reported that a long walk to school affected the students' performance as compared with living close to the school environment.
This study also showed that most of the respondents (80.7%) watched or played games.More than 44% of the students spent more than 2 hours per day on such activities, and only 9.0% played less than 1 hour per day.Respondents who watched and played games ≥2 hours were more likely to receive a 'fair' GPA than those who did not watch and play games or who did it for <2 hours (Figure 2).If students spend most of their free time watching or playing games, they might have less time for their studies.A previous study reported a similar result, namely that those who watched television for >2 hours per day were characterised by a lower academic achievement than those who watched television for <2 hours [32].
Instead of game playing and watching, individuals aged 5-17 years should spend at least 60 minutes per day performing physical activity of moderate-to-vigorous intensity according to the Myanmar Clinical Practice Guidelines for the Management of Obesity [33].
An association between the father's or mother's education and academic achievement of the student was observed.Respondents whose fathers or mother had less then or only primary education level fell were more prone to receive a 'fair' GPA than those whose fathers had at least or more than middle or higher education level (Figure 3).There were also statistically signi cant associations between high family income, parents' marital status, and good academic achievement (p = 0.000).Respondents whose parents were dead or divorced scored more 'fair' GPAs than those whose parents were both alive.We assume that parents who had higher education, higher income, and who are both alive might be able to support a better quality life to their children and invest more in their children's education.These ndings were supported by a previous study [24].Our nding with correlation analysis is able to observe participants in a public setting or in real-life scenarios no matter where or how the variables get measured.However, the major limitations of our study is only used chi squared test to determine the association between nutrition-related factors.Regression analysis should be performed to control for covariates and confounders and determine what variables have the most in uence.This would affect the results in a major way.It also noted that only two schools selected in this study would in uence the interpretation of results variability, which may lead to bias.The results could be skewed from the opinions of the speci c groups.

Conclusions
The appropriate quantity and quality of nourishment could enhance the nutritional status and also the physical and cognitive abilities of adolescents in school.There are many factors that in uenced the nutritional status of adolescent students eg.food choices habit, food intake amount, eating behavior, lack of nutritional knowledge, availability of food, socioeconomic status of student's family and physical activity.This study noticed the impact of nutritional status and its related factors on academic achievement of adolescents.This includes the number of meals per day, the duration of watching or playing games and the duration of walk to school, parent education, family income and the marital status of the parents.In order to explore the speci c nutrients requirement of adolescents in further detail, weighed dietary records or 24-hour recalls may also be combined.Researchers will use research results to apply for further study to get more speci c details of problem.School may consider to provide more meals and physical activities to students.Education academic o cers should provide the right nutritional knowledge to both students and parents.This evidence-based would be a part to assist the policy makers in Myanmar to design health and nutrition policies which are related to promote nutritional status of adolescents.It would also aid the development of new strategies to improve health for children and adolescents and reduce the burden of nutrition related problems in the public.

Figure 1 Association
Figure 1 1) Basic Education High School, and 169 (56.1%) were from No. (2) Basic Education High School.The mean age of the participants was 14.43 (range, 13-17) years, with 22.3% aged 13, 21.9% aged 14, 46.8% aged 15, 8.3% aged 16, and 0.7% aged 17.The majority of the recorded BMI values were within the normal range (69.4%).Participants who were underweight, overweight or obese constituted 22.6%, 4.7%, and 3.3% of the study population respectively.A total of 211 participants (70.1%) had normal waist-hip ratios, while the remaining 90 (29.9%) were at substantially increased risk of metabolic complications.With regard to academic achievement, 41.5% of the students got grade A, 36.2% got grade B, 15.3% got grade C, and 7.0% got Grade D based on the GPA-based evaluation (Table

Table 2
Frequencies and percentage of maximum, minimum and never consumption of food in last one month

Table 3
Knowledge, attitude, eating behavior, physical activity and nutritional status