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 fish, 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 find 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 identified [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 [20–22]. Although walking to school was the most common physical activity performed by the participants, our study failed to find any association between physical activity and nutritional status.
Thus, in this study, eating lower than three meals per day appeared to be the strongest influencing 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 deficiencies. 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 findings from this study might be beneficial for implementing intervention strategies that could reduce skipping meals and provide healthy snacks to adolescents.
This study identified no association between socioeconomic factors and nutritional status. This finding was inconsistent with previous findings [24–26]. This might be explained by the low cost of living that allow for the purchase of healthy foods.
We identified a statistically significant 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 deficiencies 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 finding 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 normal-weight 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 reflected 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 finding 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 finding 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 significant 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 findings were supported by a previous study [24]. Our finding 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 influence. This would affect the results in a major way. It also noted that only two schools selected in this study would influence the interpretation of results variability, which may lead to bias. The results could be skewed from the opinions of the specific groups.