Incidence of obesity in American school-age children: Causes and solutions

The incidence of overweight and obesity among Americans living in the United States has reached epidemic proportions. The Centers for Disease Control (CDC) estimate that 61% of the population has a BMI ≧ 25. However, the rate of childhood obesity is even greater. The number of obese children (95th percentile of BMI: ≧ 30) has more than doubled from 1976 to 2000 in 6-11 yr olds and has more than tripled (95th percentile of BMI: ≧ 30, for 12-19 year olds. The incidence of obesity is somewhat higher in males compared to females, higher in black and Hispanic children, relative to white children. Since obese children usually grow up to become obese adults, this becomes a major health issue for the American population in the future. The cause of this rise in obesity appears to be related primarily to a lack of caloric expenditure. Recent studies do not support the hypothesis that energy intake is greater in children. However, there is no doubt that the selection of foods is a contributing factor. The CDC reports that 51% of children eat less than one serving of fruit/day. The lack of physical activity is a major concern. Other than the home, children spend the greatest amount of time in the school. School-based physical education programs have diminished drastically over the past 30 years. The percentage of U.S. schools that require physical education decreases dramtically with the age of the child. Physical education requirements go from 50% to less than 6% in the 11th and 12th grade, the last two years of high school. Many states do not require any physical education. Illinois is the only state to mandate daily PE from kindergarten through the 12th grade. Physical activity in the home environment is almost non-existent. Watching television and playing video games (and now the advent of the internet!) has become a major time consumer. U.S. children watch an average of 24 hours of television each week. Research has shown a strong relationship between hours spent watching TV daily and obesity. Children spending more than 5 hrs/day in front of the TV are more than three times more likely to become obese as compared to children watching only 0-2 hrs/day. Solutions to this problem are aimed at increasing enjoyable activities in the schools and limiting TV time and other sedentary behaviors in the home environment. Copyright © 2004 The Hong Kong Institute of Education.