Our subjects were divided into 2 groups: the normal and the obese, according to the obesity index (%) (). The total numbers of subjects were 799, with 49.3 (%) male and 50.7 (%) female. The distribution of age and sex in two groups were similar. The mean age of the subjects was 11years (0.6), ranged 11-12 years. The Mean Obesity index (%) of the normal and the obese were -3.2% (11.4) and 33.4% (10.3) respectively (p<0.05). The percentages of normal and obese children were 86.5% (691) and 13.5% (108) respectively. Ten percent of females and 16.8% of males among all children were obese (p<0.05). Of the family histories of chronic diseases surveyed, significantly the higher family history of obesity in the obese group, compared to normal children (41.8% in the obese vs 14.4% in the normal (p<0.05)) was reported. Obese children had 32% of family histories of diabetes and 21% of high blood pressure. But those values were not statistically different with the percentage of the normal's family histories.
Demographic characteristics of the subjects
In , similar trends in eating frequencies in grains, meats and beans, fruits, and dairy products were found between normal and obese children. Almost two-thirds of obese children in the study (67.7%) consumed more than 3 grain servings per day, recommended KDRIs food guide. Only one-third (26.9%) of obese childrens consumed recommended daily servings of meat and bean groups. In reported fruit intakes, 56.9% of obese child met recommended daily servings of fruits. A slightly higher percentage of obese children (62%) consumed more daily recommended servings of dairy products than the normal (55%) without significant differences.
Reported number of servings of major foods and snacks
The eating practices in vegetables (p<0.05) and snacks (p<0.05) were somewhat different between normal and obese children. A greater percentage of normal children (58%) met KDRIs guidelines of vegetables, 5 servings a day, than obese children (38.9%) (p<0.05). More obese children reported eating both high fat- and high sugar-snacks every day than did normal children (sweets: 30.6% vs 10.4% (p<0.05), chips: 30.6% vs 12.0% (p<0.05)). Among obese children, 35.1% of obese children reported eating sweet snacks 3 times per week, with 30.6% eating every day and 34.3% eating less than 3 times per week. About 38% of the obese children reported eating high fat snacks 3 times per week, 30.6%, everyday and 35.2%, less than three times per week.
According to the Health Guideline for school children, children are recommended to have at least 60 minutes of physical activity daily and to have limitation of inactive forms of play (Corbin Pangrazi, 1998a
). , 71% of the obese and 57.6% of the normal reported exercising less than 1 hour per day at home, and those values were statistically different (p<0.05). About 1/3 of the obese (27%) had physical activities at home for 1-2 hours per day and only 1.9% for more than 2 hours per day. Sixty two percent (62%) of obese children played games for more than 2 hours per day, compared with 55% of the normal (p<0.05). Only 14.8% of the obese reported playing computers (computer games) less than 1 hour per day and 23% for 1-2 hour/day. There was no significant difference in daily hours of TV viewing between the normal and the obese. Only 33% of the obese reported watching television less than 1 hour per day, 33% for 1-2 hour/day, and 33% for more than 2 hours/day.
Reported physical activity practice by obese and normal children
includes the results of the association between various factors and obesity. Gender was shown to be significantly associated with the probability of obesity. Girls showed less likelihood of being obese with statistical significance (odds ratio, 0.575, CI (0.380, 0.870), p<0.05). A family history of obesity almost doubled the likelihood of obesity in children (odds ratio, 2.653, CI (1.660, 4.241), p<0.05). The number of servings of grains, meats and beans, dairy products, and fruits, according to KDRIs guidelines, had no protective effect on obesity in children. Eating 5 or more vegetable servings per day showed protective association with obesity (odds ratio, 0.460, CI (0.304, 0.697), p<0.05). Eating high fat snacks, such as chips, everyday increased double likely to be obese than eating less than 3 times per week (odds ratio, 1.91, CI (1.207, 3.2051), p<0.05). Exercising one or more hours per day significantly decreased likelihood of being obese (odds ratio, 0.572, CI (0.354, 0.0.925), p<0.05).
Odds Ratios (ORs) and 95% Confidence Intervals (CI) for selected factors associated with obese children