Additionally, a high BMI in children younger than 2 years of age is less likely to persist than a high BMI in older children (Guo et al., 1994). BMI reference values are not established for children less than 2 years of age. Weight-for-length greater than the 95th percentile is used by CDC and the Special Supplemental Nutrition Program for Women, Infants, and Children to define overweight for children in this age group.

It is important that government agencies, researchers, health-care providers, insurers, and others agree on the same definition of childhood obesity. Although varying definitions have arisen from many uses of the term in public health, clinical medicine, insurance coverage, government programs and other settings, to the extent possible, there should be concurrence on definitions and terminology.

In this report, the term “obese” refers to children and youth between the ages of 2 and 18 years who have BMIs equal to or greater than the 95th percentile of the age- and gender-specific BMI charts developed by CDC.1


To “prevent” means simply to take prior anticipatory action to hinder the occurrence of a course or event. Prevention efforts related to health traditionally have focused on preventing disease, particularly infectious disease. Conceptual frameworks have been developed that categorize health-related prevention efforts based on the segment of the population to which they are directed: the entire population (universal or population-based prevention); those who are at high risk of developing a disease (selective or high-risk prevention); or those who have a disease (targeted or indicated prevention) (Gordon, 1983; Rose, 1992; IOM, 1994; WHO, 2000).

Another traditional approach categorizes prevention according to disease progression: primary prevention involves avoiding the occurrence of a disease in a population; secondary prevention is aimed at early detection of the disease to limit its occurrence; and tertiary prevention is focused on limiting the consequences of the disease (DHHS, 2000).

A more recent framework conceptualizes a spectrum of prevention based on where—from the individual to the broader environment—the prevention actions are directed. Approaches include strengthening individual knowledge and skills, providing community education, educating


This definition is consistent with current CDC recommendations with the exception of the terminology. International references such as the International Obesity Task Force or Cole BMI values allow for cross-cultural comparisons. These references use different populations and slightly differing techniques for developing cut-off points (Flegal et al., 2001).

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