Zalilah MS, Khor GL, Mirnalini K, Norimah AK, Ang M
Correspondence: Dr Zalilah Mohd Shariff, zalilah@medic.upm.edu.my
ABSTRACT
Introduction Paediatric obesity is a public health concern worldwide as it can track into adulthood and increase the risk of adult morbidity and mortality. While the aetiology of obesity is multi-factorial, the roles of diet and physical activity are controversial. Thus, the purpose of this study was to report on the differences in energy intake, diet composition, time spent doing physical activity and energy expenditure among underweight (UW), normal weight (NW) and at-risk of overweight (OW) Malaysian adolescents (317 females and 301 males) aged 11-15 years.
Methods This was a cross-sectional study with 6,555 adolescents measured for weights and heights for body mass index (BMI) categorisation. A total of 618 subjects were randomly selected from each BMI category according to gender. The subjects' dietary intake and physical activity were assessed using self-reported three-day food and activity records, respectively. Dietary intake components included total energy and macronutrient intakes. Energy expenditure was calculated as a sum of energy expended for basal metabolic rate and physical activity. Time spent (in minutes) in low, medium and high intensity activities was also calculated.
Results The OW adolescents had the highest crude energy intake and energy expenditure. However, after adjusting for body weight, the OW subjects had the lowest energy intake and energy expenditure (p-value is less than 0.001). The study groups did not differ significantly in time spent for low, medium and high intensity activities. Macronutrient intakes differed significantly only among the girls where the OW group had the highest intakes compared to UW and NW groups (p-value is less than 0.05). All study groups had greater than 30 percent and less than 55 percent of energy intake from fat and carbohydrate, respectively.
Conclusion The data suggested that a combination of low energy expenditure adjusted for body weight and high dietary fat intake may be associated with overweight and obesity among adolescents. To prevent overweight and obesity among children and adolescents, strategies that address eating behaviours and physical activity are required. Various segments of the society must be involved in efforts to promote healthful dietary intakes and active lifestyle in children and adolescents.
Keywords: adolescents, dietary intake, energy expenditure, energy intake, obesity, physical activity
Singapore Med J 2006; 47(6): 491-498