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Food for Thought

Janet Raloff
Food for Thought

Honey, Let's Shrink the Kids

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"Despite steady progress over most of the past century toward assuring the health of our country's children, we begin the 21st century with a startling set-back—an epidemic of childhood obesity."

So begins a 480-page report that was released in preprint form last week by the Institute of Medicine (IOM). Although this epidemic affects boys and girls in all states, at all ages, and in all income brackets, the report notes that certain ethnic groups suffer disproportionately—especially blacks, Hispanics, and Native Americans.

Congress didn't commission the IOM to confirm the magnitude of childhood obesity, however. That a serious problem exists was taken for granted. Rather, Congress asked for a panel of experts to develop guidelines for an action plan to reverse this epidemic, focusing on the factors that are fostering weight gain in the youngest members of society.

After 2 years of hearings and fact-finding, the 19-member panel distilled its recommendations into two categories: promoting healthful eating and encouraging regular physical exercise.

"The federal government must provide the leadership that is needed to make obesity prevention a national public health priority," said panel chairman Jeffrey Koplan of Emory University at the release of the new report. He said the government must develop surveillance programs for identifying children at highest risk of becoming obese and offer guidance on how young people can be trained to change their eating and exercise habits.

Moreover, he said, "as the nation focuses on obesity as a health problem and begins to address [its causes], many different groups, industries, and organizations will need to make difficult tradeoffs and choices." For instance, the panel calls on the food and beverage industries to change their advertising and marketing strategies—such as offering smaller, lower-calorie portions of their goods—to "minimize the risk of obesity in children and youth."

Local governments and communities should make more parks, sidewalks, and bike paths available to kids, especially in areas with high proportions of kids at risk of obesity, the panel said. Schools should budget "a minimum of 30 minutes of moderate-to-vigorous physical activity during the school day" for each child. This could counter a trend seen in many public schools today, where children sometimes get recess or organized gym classes no more than once a week.

Even parents are being asked to change their lifestyles dramatically. The IOM panel would have moms begin with "exclusive breast-feeding as the method for feeding infants for the first 4 to 6 months of life." Then, it asks parents to encourage exercise and to limit their kids' couch-potato recreation—television and computer time—to less than 2 hours a day.

How bad a bulge?

Today, some 9 million U.S. children over age 6 are considered truly fat—that is, their weight is in the top 5 percent of children their age, gender, and height. Even though such children are obese, physicians have traditionally referred to them as "overweight," the new report observes, out of concern that the former term was too pejorative. However, the new panel said it chooses the harsher term because "'obese' more effectively conveys the seriousness, urgency, and medical nature of this concern . . . thereby reinforcing the importance of taking immediate action."

Obesity's prevalence has more than tripled for children ages 6 to 11 over the past 30 years and more than doubled among preschoolers and teens, the panel found. At a minimum, its report notes, these children now face an elevated risk of psychosocial burdens related to being obese in a society that stigmatizes this condition. In the long run, however, that may be the least of their problems.

Current obesity rates appear to put 30 percent of boys and 40 percent of girls born since 2000 at risk of eventually developing type 2 diabetes. Indeed, studies indicate that 8 to 45 percent of diabetes cases in children are now turning out to be the type 2 kind—a form often linked to obesity and that until recently was known as adult-onset diabetes. As recently as 1990, type 2 disease accounted for only 4 percent of pediatric diabetes.

The new report also cites data indicating that roughly 60 percent of obese youngsters 5 to 10 years old exhibit at least one risk factor for cardiovascular disease, such as elevated cholesterol, triglycerides, insulin, or blood pressure. One-quarter of these kids actually has at least two risk factors.

Because of the potentially lethal nature of conditions linked with obesity—including heart disease, diabetes, and certain cancers (see Surprise! Obesity (and Inactivity) Can Spur Cancers)—the childhood-obesity epidemic threatens to reverse the trend in improved life expectancy achieved over the past century, the IOM panel says.

Attack it like smoking

It's one thing to describe pediatric obesity as unhealthy and quite another to commit the nation to policies that would significantly reduce the problem. The former is what society has done, while watching its children get fatter. The latter is what the United States must now pledge to do, the IOM panel argues, adding that it won't be easy.

Indeed, Koplan acknowledged, "because the epidemic has taken years to develop, it will require a sustained commitment of effort and resources spanning many years—possibly decades—to effectively address the problem." His panel likened the resolve necessary to slim down the nation's children to that behind the nation's youth-antismoking campaign.

In that program, not only were parents and other adult role models asked to shun cigarettes, but also communities passed ordinances that made buying cigarettes harder for kids, such as by banning or limiting vending-machine sales. Television ads for cigarettes were banned, and many towns prohibited smoking in public buildings. States increasingly raised their taxes on tobacco in attempts to price it beyond the budgets of young people. Simultaneously, an aggressive public health campaign repeatedly told of the adverse health effects of smoking.

The IOM panel advocates a similar societywide, multipronged approach to fighting childhood obesity. All segments of government should be charged with evaluating what might be done to remove obstacles to exercise and good nutrition, insists the IOM report.

If highway traffic makes it unsafe for children to walk through their community, transportation officials should look for solutions. Communities should build bike paths and green space where children can play in safety, the report says.

Fast-food and full-service restaurants should more routinely label the nutrient content of their offerings, the IOM panel said, so patrons could make more-informed dining choices. It also recommended that restaurants:

  • "explore price incentives that encourage consumers to order smaller meal portions"
  • more routinely offer fruits, vegetables, low-fat milk, and caloriefree drinks
  • make it easier for parents to substitute such healthful foods for high-calorie ones when they order for their kids
  • discourage free seconds of non-nutritious foods and drinks

Class acts

At least 28 million youngsters derive about a third of each weekday's calories from school lunches, and roughly 8 million kids get their breakfasts at school as well. These tallies don't take into account vending-machine sales for snacks. Most children also expend about half of their energy at school, according to the new report.

Thus acknowledging the pivotal role that educational institutions play in the lives of most youngsters, the IOM panel recommends that schools become more assertive in teaching—and providing—better nutrition and exercise. Indeed, the new report gives schools poor marks for their current practices.

The IOM panel found that although many schools offer healthful meals in school cafeterias, they also give students à la carte options that might best be described as junk foods: cookies, candy bars, potato chips, and other salty or high-fat snack foods. In fact, a pair of General Accounting Office reports last year concluded that the presence of such sweet, high-fat snacks in vending machines and on cafeteria lines undercuts efforts by schools to improve the nutrition of U.S. youngsters (see School Lunches are Struggling to Earn High Marks).

This past May, The Center for Science in the Public Interest (CSPI), a nutrition-advocacy group, reported on its nationwide survey of vending-machine offerings in 251 middle schools and high schools. It found that 75 percent of the drinks and 85 percent of the snacks sold in these automated centers had poor nutritional quality.

For instance, 70 percent of the drinks sold in vending machines were sugary soda pops, sweetened iced teas, sports drinks, or fruit drinks containing less than 50 percent real juice. Of the soft drinks, only 14 percent were sugarfree. Just 5 percent of drink offerings were milk, and only 40 percent of those were low fat or skim. Of snack foods, candy accounted for 42 percent of the offerings, chips made up 25 percent, and sweetened baked goods accounted for 13 percent of the choices. Of 9,723 vending-machine slots counted in the survey offering snack foods, only 26 contained a fruit or vegetable.

"It's hard enough for parents to guide their children's food choices, but it becomes virtually impossible when public schools are peddling junk food throughout the school day," concludes Margo G. Wootan of CSPI.

The IOM panel agrees. Because student food choices are influenced by the range of available foods, not the simple presence of healthful offerings, such as fruits and vegetables, the panel says that restricting the availability of high-fat, high-sugar foods "might be an effective strategy for promoting more healthful food choices among students."

It argues that schools "need to ensure that all meals served or sold in schools are in compliance with the [healthful] guidelines" issued 4 years ago by the U.S. Department of Agriculture. Known as the Dietary Guidelines for Americans, these precepts call for eating a variety of foods daily in the basic food groups: fruits and vegetables, whole grains, and nonfat or low-fat milk and milk products. The guidelines also call for both adults and kids to exercise daily, hold down calorie intake to manage weight, use little salt, limit saturated and trans-fat intakes, and cut sugar consumption.

The IOM panel also "proposes that USDA conduct pilot studies to examine the benefits and costs of providing full funding for school breakfast, lunch, and snack programs in a targeted subset of schools that include a large percentage of children at high risk for obesity." Findings from the studies could be used to set policies on the types of foods offered at schools nationally and how they might be priced—so as not to undercut support for more-healthful fare. The panel also recommends teaching good nutrition in classes at every grade level, beginning with kindergarten.

Kick it up a notch

Although most schools offer recess and some regular physical education (PE) classes, many don't demand energetic participation by kids. Indeed, one study cited in the new report found that in a 30-minute elementary school PE class, "the average child was vigorously active for only 1 to 3 minutes." Another study found that in the typical 45-minute PE class, overall, just 25 minutes or so were spent in games, sports, drills, or dance. And among high school students, last year, only 55 percent even took PE.

The new report asks schools to ensure that all students engage in at least 30 minutes of moderate-to-vigorous activity daily. One way to do this is to expand opportunities for exercise in after-school clubs and sports programs. The panel also advocates that communities "promote walking and bicycling to school"—a policy that would require more support in the form of crossing guards, bike racks, and education on commuting safety.

Finally, the new report calls on families to reinforce all of these messages at home and for parents to serve as role models by themselves adopting healthful eating and exercise behaviors.

Moreover, the panel advises parents to "allow children to determine their own portions at meals"—with no more insistence "on their 'cleaning their plate'." Similarly, food should not be used as a reward, the panel said, because that practice "dissociates eating from hunger." Families should keep fruits and veggies readily available to encourage their selection as snacks and desserts, and when cookies, pizza, or other calorie-dense foods are offered, serving sizes should be kept small.

Concludes Koplan, "This report is calling for fundamental changes in our society."

Citations

Jeffrey P. Koplan

Woodruff Health Sciences Center

Emory University

Atlanta, GA 30322

Institute of Medicine

National Academies of Science

2101 Constitution Avenue, NW

Washington, DC 20418

Margo Wootan

Center for Science in the Public Interest

1875 Connecticut Avenue, NW, #300

Washington, DC 20009
Further Reading

Raloff, J. 2004. When it's no longer baby fat. Science News Online (April 17). Available at [Go to].

______. 2003. School lunches are struggling to earn high marks. Science News Online (May 17). Available at [Go to].

______. 2002. Surprise! Obesity (and inactivity) can spur cancers. Science News Online (Aug. 3). Available at [Go to].

U.S. Department of Agriculture. 2000. Nutrition and Your Health: Dietary Guidelines for Americans. Available at [Go to].

U.S. General Accounting Office. 2003. School Lunch Program: Efforts Needed to Improve Nutrition and Encourage Healthy Eating. Report GAO-03-506. Available at [Go to].

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