Childhood obesity on the rise in the U.S.

Childhood obesity is on the rise. The 2007-2008 National health and Nutrition Examination Survey found 17 percent of American children and adolescents ages 2 to 19 years are obese.

Among pre-school-age children aged 2 to 5 years, obesity increased from 5 between 1976 and 1980 to 10.4 percent between 2007 and 2008. 

Among 6 to 11 years olds, obesity increased from 6.5 to 19.6 percent and among adolescents aged 12 to 19, obesity increased from 5 to 18.1 percent during the the same period.

Childhood obesity is associated with health conditions such as cardiovascular disease, high blood pressure, high cholesterol, and Type 2 diabetes than their peers with normal weight.

A report titled F as in Fat: How Obesity Threatens America's Future 2010 released on June 30 by Trust for America's Health and Robert Wood Johnson Foundation says currently, more than 12 million children and adolescents are considered obese, compared to 25 percent of adults in 38 states.

Obese children and adolescents are also more likely to become obese after they enter adulthood.  One study showed that 80 percent of children overweight at the age of 10 to 15 years ended up becoming obese at the age of 25 years.

For children aged 2 to 19, childhood obesity is defined as a BMI at or above the 95th percentile for children of the same age and sex, according to the United States Centers for Disease Control and Prevention.

What are the contributing factors for childhood obesity?

Obesity results from excessive intake of energy meaning a person eats more than he needs.  But energy intake is not the only thing that affects a person's weight gain or loss. Genetics and physical activity among other things affect a person's weight status as well.

Parental behaviors like healthy lifestyle and dietary habit also affect children's weight status.  

Even pregnant women's prenatal weight can raise risk of childhood obesity in their children, according to a study published in Jun 15, 2010 issue of Circulation.

Fraser A. of the University of Bristol and colleagues found gestational weight gain and prepregnancy obesity can both raise the risk for children to become obese at the age of 9 years.

By David Liu