Potential Factors related to BMI among School going adolescents of Madurai District, Tamil Nadu, India

This study aims to recognize essential aspects (related to lifestyle, eating and sedentary behaviours) of overweight and obesity among school-going adolescents of Madurai District, Tamil Nadu. Data were elicited on the physical activity patterns, sedentary practices at home, sleep duration and lifestyle behaviours such as habits of snacking, skipping breakfast, eating in front of television and frequency of eating out. Among 7660 subjects, 514 samples were found to be overweight and obese and analyzed with the suitable statistical tools such as percentage analysis, chi-square test to check the level of signi icance. 74.4 per cent of obese adolescents were found to have the habit of consuming snacks. The prevalence of Overweight 95 (18.48%) and obese 315 (61.28%)wasmore signi icant inNuclear families. However, therewas no statistically signi icant association between family type andBMI (χ = 2.575, p > .05). No statistical associationwas found between the BMI and snacking and eating patterns of school-going adolescents. Majority of 364 children expenditure towards snacks are less than Rs.25.


INTRODUCTION
Globally, obesity had nearly tripled ever since 1975. In 2016, Over 650 million adults were obese, including more than 1.9 billion overweight adults. Of these over 650 million were obese. Around 340 million school-going children and adolescents of 5-19 years were neither overweight nor obese in 2016. The prevalence of overweight and obesity among schoolgoing children and adolescents belonging to 5-19 years age group has risen intensely from just 4% in 1975 to over 18% in 2016. The upsurge has arisen similarly among both the genders: in 2016, 18% of girls and 19% of boys were overweight (WHO, 2018). Once, overweight and obesity were believed as a problem of high-income countries but, now it is increasing in low income and middle-income countries, particularly in urban areas.
The vital cause of obesity is an energy imbalance between calories consumed and depleted. Changes in dietary and physical activity patterns are often the outcome of environmental and societal changes globally. Numerous trends in eating patterns have concurred with the increase in obesity rate, including large portion sizes, rise in the intake of food prepared outside the home and increases in the contribution of snacks to total energy intake. But, the impact of obesity in children and adolescents is not yet well understood. In precise, there is a lack of consensus regarding the factors related to BMI to enlighten the development of recommendations and interventions (Larson and Story, 2013).  This study aimed to 1) observe eating habits, patterns of snacking behaviour (including Pocket money spent on snacks, preference of snacks, frequency of consumption and reason for snacking); and 2) evaluate the association between snacking behaviours, physical activity levels and BMI.

MATERIALS AND METHODS
A cross-sectional study was conducted in Government and Private Schools of Madurai District, Tamil Nadu, which comprised questionnaire framing, quantitative data collection and interpretation. School-going adolescents aged 13-18 years from the Government and private schools of Madurai District, Tamil Nadu were selected irrespective of their religious status, gender and residential area. Later, random sampling methods were utilized on each stratum to obtain the inal study sample size (N=514). Eligibility criteria included the following: 1) aged 13-18 years; 2) non-smokers; 3) luent in either English or Local Language -Tamil; 4) not under medications that affect appetite or body weight; 5) not presently on a weight loss program.
The close-ended questionnaire was framed to capture students' information concerning meal pattern, living arrangement and food choices. The socio-demographic details of the students (Salma and Ramakrishnan, 2017) and anthropometric measurements such as height and weight were measured using a stadiometer and a digital weighing scale, respectively. Based on these measurements, (Kuczmarski et al., 2000) BMI-for-age child growth charts (Normal weight = ≥5 th to <85 th Percentile, Overweight = ≥85 th to <95 th Percentile and Obese = ≥95 th Percentile) used to determine adolescent's BMI for age percentile. The choice and frequency of consumption of snacks, reason for snacking and pocket money spent on snacks were also  Seventy-six percentage of adolescents' belonged to lower socio-economic while twenty-one percentage were classi ied in upper-lower socio-economic status. These indings were statistically not signi icant with the BMI of the adolescents. Our study results were contradictory to fewer studies conducted in India (Ramachandra, 2002;Goyal et al., 2010), because of the diversity in the study population. More of our study population belonged to the lower socio-economic status than the higher or middle income. Hence, there was data insuficiency in comparison with the higher or middle socio-economic status group.

Eating Habits of School going children basing on their age
Of the total studied population, the children studying in government schools were 298. Out of 298 respondents, 26.8 per cent of the students ate their breakfast and dinner by watching television, 22.1 per cent of them had their meals with their family, and 5.44 per cent of them have their meals alone. On the other hand, similar to the government school, the majority of private school students too, ate by watching TV, and 16.3 per cent of them had their meals with family. 6.61 per cent of private school students ate alone, which is higher per cent than the government school students (Table 2). Table 3 represents the response of school-going adolescents to questions related to snacking pattern and their comparison with Body Mass Index. Obese students (BMI ≥95 th Percentile) were found to eat snacks regularly (75.2 %) compared to overweight students (24.8%), and it was not statistically significant (p=.86). Even though the school-going children preferred to nibble snacks, they did not skip the meals for snacks which is also statistically proven (p=.01). Majority of the children preferred to purchase the delicious snacks (53.89%), and this is also not signi icant with the Body Mass Index of the children (p=.01).
Eating bakery and fried foods was found more frequently among obese students (27.04%) compared to overweight students (7.19%), but it was not statistically signi icant. Most of the obese students were found to nibble snacks while watching TV, in general, and whenever happy (70.03%), and this was also not statistically signi icant with the BMI of the children. 56 per cent of adolescents spend less amount to purchase snacks.
The common perception of snacking is that snack foods are harmful as it is high in fat and sugar and not appropriate for healthy eating (Astrup et al., 2006). Adolescents habitually choose more salty and crunchy snacks than the other healthier substitutes available since they prefer tasty foods over nutritious foods. Adolescents tend to snack more when they skip their regular meal patterns, and the frequent or regular intake of snacks increases their energy and non-balanced nutrient intakes leading to overweight and obesity (Nicklas et al., 2003). Table 4 represents the relationship of physical activity performed, Body Mass Index and preference on purchasing the snacks by the school-going children.
Majority of the children preferred purchasing tasty snacks than nutritious and hygienic snacks. Children who fall under obese category found to nibble snacks more than overweight children. More students were found to play outdoor games than indoor games. Signi icantly few children showed no interest in physical activity. Association between Body Mass Index and Physical activity has no significance (p-value .062, .032) whereas preference on purchasing snacks and Physical Activity showed signi icance (p-value .000) statistically at 1% level of signi icance.

CONCLUSIONS
The present investigation was conducted on schoolgoing adolescent children (13-18 years) from Madurai District, Tamil Nadu state, India. Preventing overweight and obesity among school-going adolescents is a public health privacy improving adolescents knowledge to take balanced nutrition; to eat breakfast and meals regularly; to avoid frequent snacks and fatty food consumption; to stop eating before fullness and to do regular physical exercise may endorse maintaining healthy body weight among students and decrease the prevalence of overweight and obesity.

Author Contribution
We declare that all of the authors mentioned in the article have contributed equal efforts in this research and also for the submission of the article.