As Moran¹ describes in this issue of American Family Physician, an epidemic of childhood obesity is occurring in the United States; the prevalence of the most severe cases—defined as a body mass index (BMI) for age over the 95th percentile—has virtually doubled over the past 20 years, while the prevalence of standard cases (BMI for age over the 85th percentile) has increased about 50 percent.² Possibly because of a feeling of hopelessness about the effectiveness of treatment for obesity or an expectation that most children will “outgrow it,” textbooks of pediatrics have barely touched on the subject of childhood obesity in the past, and present-day authorities worry about the lack of efficacy of available treatment.³

Currently, a majority of resident physicians do not address the issue of obesity with their patients,⁴ and it is questionable how many practicing physicians do. However, increased interest in this subject is now apparent from publication of articles on the subject in medical journals,^5–7 from increases in funding available for research and treatment in this important area, and from frequent reports in the lay press about this subject.

Obesity in childhood persists into adulthood predominantly when there is a strong genetic component.⁸ The complications of obesity in adulthood are well known (heart disease, hypertension, type 2 diabetes mellitus [formerly known as non–insulin-dependent diabetes], etc.). Estimation of annual costs related to obesity and its complications approach $100 billion.⁹ Childhood obesity carries its own morbidity (type 2 diabetes mellitus is now the most common type of diabetes diagnosed in several pediatric diabetes centers)¹⁰ and mortality (we and others have seen children between the ages of six through 10 years with a BMI over the 99th percentile who die of sudden cardiopulmonary arrest apparently caused by arrhythmias associated with their obesity).

Treatment of obesity in children, like the treatment of obesity in adults, is expensive, lengthy and generally only effective if the whole family is involved,^11,12 and even then it is not “curative.” It is essential that our goal should be directed toward prevention, as Moran states,¹ in the entire population, with particular attention to more susceptible ethnic groups.

Obesity, determined partially by genetics and partially by the environment,¹³ is best considered a chronic disease. The increase in obesity in the United States (and a similar increase in other countries as their economies “develop”) is not caused by a change in the gene pool, but rather by changes in the environment that have caused genetically susceptible populations to express the obesity phenotype in increasing numbers. For many reasons, including fewer mandated physical education programs in schools, lack of safe areas to exercise in many inner-city neighborhoods, and the ever-present television set, physical activity levels are lower now than they were 20 years ago. Energy input (read food) has increased remarkably because of the availability of fast-foods that are high in calories and because of an increasing lack of adult supervision in the lives of many children.

Thus, a nationwide population-based approach to the prevention of childhood obesity is essential. Increasing physical activity and practical nutritional knowledge through education in schools or through extracurricular programs should be an obvious first step that may require legislative action. However, even spending one hour sweating on an exer-cycle will not work off the calories found in a fast-food meal; energy intake must be controlled in this land of super-sized portions.

A public service campaign is needed to combat the overwhelming messages of caloric and fat intake bombarding children at every turn; during one hour of watching cartoons, a young child might see advertisements for more than enough calories, fat and sodium than is appropriate for an average adult male to consume in 24 hours.¹⁴ Advertisements for children to resist inappropriate food choices and for their parents to avoid pressure from their children to buy this undesirable food could be modeled after the successful antismoking campaigns targeted at young persons.

With no safe, effective pharmacologic agent on the horizon, there is no easy answer to the treatment of childhood obesity. The prevention of this condition is a daunting task, but we cannot remain complacent and expect all overweight children to “outgrow it,” or we might find ourselves facing even more alarming statistics in 20 years as we look back to the “good old days” at the end of the 20th century when the incidence of childhood obesity was only 22 percent.¹⁵