Dietary behaviors, physical activity and sedentary lifestyle associated with the risk of being overweight and obese and having higher BMI among Pakistani primary school children, and their socio-demographic correlates, were described in the present study. Children who skipped breakfast were more likely to be overweight and obese as compared to those who regularly had their breakfast. Gender-specific trend in breakfast skipping and prevalence of overweight revealed that the relation was significant among girls but not boys. After adjusting for age, gender and all factors, skipping breakfast was a significant independent predictor of higher BMI and overweight. Previous studies have reported lower risk of overweight and lower BMI among children having breakfast regularly compared with those who frequently skip breakfast [20–24]. Female gender and living in urban area were associated with skipping breakfast, consistent with previous studies [24, 25]. Higher social class, represented by socio-demographic characteristics of the child including urban area with high SES, high-income neighborhoods, higher parental education and fewer siblings, was associated with breakfast skipping behavior. Female gender was independent predictor of skipping breakfast. The reason for breakfast skipping among females might be a higher concern for body image . Skipping breakfast had significant independent inverse association with physical activity, further contributing to increased adiposity, consistent with previous literature [27, 28]. A school-based breakfast program, especially in the urban area and among girls, could be beneficial to improve the nutritional status. Media-based health education campaigns tailored to local circumstances and targeting the higher social class could be initiated.
Children who had lunch at school and did not eat supper together with their family have been reported at an increased risk of being overweight [29, 30]; however, no significant association was observed in the present study. Higher frequency of eating fast food and snacks was associated with overweight and obesity, consistent with previous literature [30–35]. Gender-specific trend in eating fast food and snacks and prevalence of overweight revealed that the relation was significant among boys but not girls. Eating fast food and snacks showed a significant independent association with higher BMI and risk of being overweight after adjusting for age, gender and all factors. Higher consumption of fast food and snacks was observed among boys, urban children and those having higher social class depicted by high SES, high-income neighborhoods, higher parental education, both parents working, fewer siblings and less crowded housing, in line with previous studies [33–36]. Male gender, urban area with high SES and higher parental education were significant independent predictors of eating fast food and snacks. A possible explanation for the gender disparity may be higher nutrition knowledge among girls owing to their high concern with self-perception of body image , and the socio-cultural matrix in South Asia that prioritize boys in feeding practices. Parents are less likely to encourage sons to lose weight perhaps because of the larger, more muscular ideal male body shape . Eating fast food and snacks had a significant independent association with sedentary lifestyle, consistent with previous literature . Restriction on television advertising of fast foods to children, applying taxes on energy-dense foods and food labeling have proved to be useful in the developed countries .
Physical activity more than twice a week had a significant independent inverse relationship with overweight and BMI. It is well established that physical activity increases a child's energy expenditure and leads to a lower risk of overweight [2, 30, 39–43]. Correlates of higher physical activity were the rural area with low/disadvantaged SES and low-income neighborhoods. Living in the rural area was significant independent predictor of higher physical activity. Children who travelled actively to and from school by walk or bike were significantly less likely to be overweight and obese than those who were driven to and from school, consistent with previous findings [2, 44, 45]. Built environment, walking and cycling paths, public open spaces and parks, safe and inexpensive recreation and sports centers and an improved quality and duration of physical education in schools can be considered for increasing physical activity [2, 39].
Sedentary lifestyle that included television viewing, working on computer and playing video games showed a significant independent association with higher BMI and risk of being overweight, consistent with previous studies [38, 40–43, 46, 47]. Increased television viewing has been associated with a higher energy intake . Sedentary lifestyle was more common among boys, urban children and those having higher social class depicted by high SES, high-income neighborhoods, higher parental education, fewer siblings and less crowded housing. Sedentary lifestyle has been previously associated with the urban area and high SES . Behavioral interventions have shown promising results to reduce the time spent in sedentary lifestyle, especially television viewing, among children . Physical activity and sedentary lifestyle were independently associated with overweight, consistent with a recent study, and preventive strategies may need to target sedentary lifestyle and physical activity separately .
These findings can be generalized to South Asian primary school children sharing the same genetic and environmental factors with the study sample. Cross-sectional nature of the study should be considered when interpreting the findings. Future longitudinal studies involving these factors are warranted to establish the temporal nature and causality of these associations among both boys and girls. Although data collection followed a standard protocol, digital scales were not used. Variability in the data ascertainment may have introduced error into the prevalence estimates; however, we do not anticipate large or systematic differences. The responses were based on self-recall and recall bias is a recurring problem with any self-report survey; however, this limitation may be tolerable considering the goals of the questionnaire and previous studies support the validity of this methodology in school-aged children [12, 13, 15, 16].