With all the buzz around childhood obesity, it's easy to become desensitized to the statistics. But the shocking figures can't be ignored: Since 1980, the prevalence of obesity among kids and adolescents in the United States has tripled, according to the Centers for Disease Control and Prevention (CDC). Estimates from the National Health and Nutrition Examination Survey (NHANES) show that 31.7 percent of U.S. children and teens were either overweight or obese in 2008. Among low-income families and certain ethnic groups such as Hispanic boys and black girls, the rates are even higher.
The harms of extra pounds are well documented. Obese children are more likely to have high blood pressure, high cholesterol, breathing problems such as asthma and apnea, fatty liver disease and Type 2 diabetes, which historically only affected older, overweight adults.
The repercussions of excess weight extend to the brain, too. Last fall, Po Lai Yau, PhD, and colleagues at New York University's School of Medicine reported that in adolescents, obesity and metabolic syndrome (the set of obesity-related factors that increase the risk for coronary artery disease, stroke and diabetes) are linked to changes in brain structure as well as impairments in learning and attention span (Pediatrics, 2012). Obese kids and teens are also more likely to have social and psychological problems, such as depression, and are at increased risk of bullying and poor self-esteem.
The causes of obesity are just as complex as its ill effects. Think back to the "ecological model" of child development that's a staple of Psych 101, says Maureen Black, PhD, chief of the Division of Growth and Nutrition at the University of Maryland School of Medicine. The model is depicted as a series of concentric circles. The small central circle represents the child. Moving outward, the circles represent ever-broader influences on that child's development: the family, the neighborhood, the school, the community, the society at large.
"That's a perfect metaphor for obesity," Black says. Focusing exclusively on individual children is blaming the victim, she adds. Kids are getting walloped at every level with cues to eat too much and move too little.
It's clear that obesity is an intricate, obstinate problem. But multiple causes also means there are many angles from which behavioral health experts can make a mark in fighting the epidemic. "Obesity is now the second leading cause of death in the U.S. and is expected to beat out smoking to become the leading cause. It's a health-behavioral problem that's going to bankrupt the country," says 2012 APA President Suzanne Bennett Johnson, PhD, who made fighting obesity one of the central themes of her presidency. "We're not going to solve this problem if people are passive."
One obvious place for psychologists to focus their efforts is in the home. "It all starts with the family," says Leonard Epstein, PhD, chief of the Division of Behavioral Medicine at the University at Buffalo.
In studies over 30 years, Epstein has found that the most successful ways to help kids shed pounds are interventions that combine diet, physical activity and behavioral recommendations. In an analysis of more than a dozen studies, Epstein, along with Denise Wilfley, PhD, director of the Weight Management and Eating Disorders Program at Washington University in St. Louis, and colleagues concluded that such lifestyle-based interventions lead to meaningful long-term weight loss in kids (Health Psychology, 2007).
The shape of those interventions isn't always intuitive, however. That's why solid research is so important. For example, most obesity treatments focus on what people shouldn't eat, Epstein says. But he has discovered that kids lose more weight when behavioral treatments focus on increasing fruits and vegetables, rather than avoiding high-calorie foods (Obesity, 2008).
The most effective lifestyle interventions are those that target both parents and children simultaneously. "Obese kids live in families with obese parents, and kids model their parents' behaviors," Epstein says. Helping parents and children modify those behaviors as a family leads to greater weight loss than similar programs that focus on kids alone (Health Psychology, 1994).
According to Wilfley, the trick is to help parents engineer healthy home environments — removing TVs from bedrooms, limiting computer time, making physical activity a routine for the entire family, and teaching parents how to find and prepare nutritious foods on a budget. "There's a lot of room for making healthy fruits and vegetables a default choice, but it takes a lot of conscious decision-making and going out of your way," she says.
Simply teaching people the healthy basics isn't enough. "It's unrealistic to feel we can have people completely change habits and behaviors with just education alone," Wilfley says. Behavioral interventions lasting up to a year are necessary to help most families implement changes that will last in the long run.
She's developed a program to help kids and families keep weight off after they've done the hard work of losing it. Her intervention, which she calls social facilitation maintenance treatment, helps build social support and routines for healthy behaviors by extending the intervention across the home, peer and community environments (Journal of the American Medical Association, 2007).
Early interventions are also key. A variety of studies have shown that overweight babies are more likely to become overweight kids, and overweight kids are more likely to become overweight and obese adults. Among low-income families, one in seven children is already obese by the time he or she enters preschool. "If we're going to get our arms around this, we should start early," Black says.
Helping families is well and good, but a one-by-one approach presents an obvious challenge in reaching all 12.5 million American children and adolescents who are obese. Schools — where most kids spend most of their days — are obvious targets.
Schools can make sweeping changes and reach huge numbers of young people with relative ease, says Gary Foster, PhD, who directs the Center for Obesity Research and Education at Temple University. "Clinic-based approaches are incredibly important, but from a public-health perspective, it's easier to work with 3,000 individual families. You can make structural changes in a school just because the principal said so," he says.
Kids consume 35 percent to 50 percent of their total calories at school, according to Jamie Chriqui, PhD, a senior research scientist at the University of Illinois at Chicago's Institute for Health Research and Policy, who presented her findings on school foods at APA's 2012 Annual Convention in August. Many of those calories come from so-called "competitive foods" — vending machines, school stores and à la carte cafeteria offerings that typically include cookies, candy and chips. According to Chriqui, more than half of elementary schools, and nearly 90 percent of high schools, offer à la carte lines.
Fortunately, vending machines and snack bars are likely to skew healthier in the very near future. In 2010, Congress passed the Healthy, Hunger-Free Kids Act, which set new policies for the USDA's child nutrition programs, including the National School Lunch Program. The law (which is still in the process of being implemented) will improve school meals by reducing fat and increasing whole grains, fresh fruits and vegetables. What's more, the law also requires the USDA to create nutritional standards for all of the competitive foods sold in schools.
There's reason to be optimistic that the impending law could make a difference. In August, Daniel Taber, PhD, MPH, also at the University of Illinois at Chicago, and colleagues reported the results of a study that tracked more than 6,000 students in 40 states. Kids in states with strict laws governing the sale of snacks and sodas in schools gained less weight from fifth grade to eighth grade than those in states with weaker junk-food regulations (Pediatrics, 2012).
Overall, though, school-based interventions have had mixed results, says Foster. One of his studies, for instance, compared schools that implemented a nutrition policy with schools that did not, following fourth through sixth graders for two years. The intervention cut the incidence of overweight students by half, from 15 percent in control schools to 7.5 percent in intervention schools. That's good news, Foster notes — but the fact that nearly 8 percent of kids became overweight even with the intervention is worrisome. And while overweight rates improved, the incidence of more-extreme obesity didn't budge (Pediatrics, 2008).
Another of Foster's projects, the National Institutes of Health-funded HEALTHY Study, targeted middle schools in low-income neighborhoods. This intervention was much more aggressive: overhauling the cafeteria menu, boosting physical activity and teaching kids about health and nutrition with classroom activities. The intensive intervention paid off, lowering obesity rates between sixth and eighth grade (New England Journal of Medicine, 2010).
Unfortunately, for both overweight and obesity rates combined, schools that didn't receive the intervention did just as well as those that did; both saw a 4 percent drop in combined overweight-obesity prevalence. While that finding muddied the results a bit, Foster says, it's actually good news. "There's something happening in the environment in the poorest neighborhoods" that caused those rates to fall, he says. More work needs to be done to figure out what that something is — and which school programs are most effective.
Of course, healthy schools are only one part of a healthy community. When Foster explored why kids were still becoming overweight despite the school interventions, he discovered that kids in his mostly urban study population were stopping at corner stores before and after school to buy the sodas, chips and candy that had been purged from their lunchrooms. On average, every store visit resulted in about 360 extra calories, though the average kid only spent about a dollar (Pediatrics, 2009).
Foster is now working on a pilot project to help store owners offer healthier options without chipping into their profits. "The bottom line from a corner store owner's point of view is, ‘Look, if I can make the same profit and sell healthier foods, why wouldn't I?'" he says. "If you can buy apples and bananas in the corner store, and if they're cheap, you might have a fighting chance."
A toxic environment
Most psychologists are accustomed to working at the level of the individual or the family. But to halt the obesity crisis, we must think bigger, argues Kelly Brownell, PhD, director of Yale University's Rudd Center for Food Policy and Obesity. In August, Brownell received one of two 2012 APA Awards for Outstanding Lifetime Contributions to Psychology for his top-down approach to battling our nation's ballooning waistlines.
"We've tried [a personal-responsibility approach] for 30 years and it's not working," he says. "Treatment is good for people who receive it, but it's very expensive and there's just no way you could do it on a broad enough scale to reduce the prevalence of obesity." Instead, he's focused his efforts on the "obesogenic" environment in which we live — in other words, the toxic food environment that contributes to obesity.
To that end, making schools healthier is a top priority, Brownell says. He's optimistic that the Healthy, Hunger-Free Kids Act will help pave the way. Yet plenty of challenges remain.
The average American child watches about 15 food commercials per day, according to Rudd Center figures. Most ads tempt kids with images of sugar-sweetened beverages, cookies, chips and other high-calorie, high-fat snacks. Concerned about the effects of those ads, the Federal Trade Commission is carefully watching food advertisements and plans to release a report detailing how food companies market to kids. However, there's little the FTC can do beyond monitoring. Last year, it joined several other government agencies to create voluntary guidelines for marketing food to kids. But the interagency group fell apart after the food industry balked at the draft guidelines, and final recommendations were never released.
It's virtually impossible to compete with food companies' influence and deep pockets, Brownell says — "unless the country takes on the industry rather than continually yielding to it."
For starters, that might mean passing laws limiting food marketing to kids. Another important step, he says, will be to adjust the relative price of healthy versus unhealthy foods. Highly processed junk foods are often cheaper than fruit or other healthy, "whole" foods.
One way to address that imbalance is through a tax on sugar-sweetened drinks, an initiative that Brownell has pushed in his work at the Rudd Center. Though controversial, such taxes have been considered in a number of states and communities, and several other countries have enacted junk-food taxes to limit soda consumption. Brownell and his colleagues estimated that a penny-per-ounce tax on sugar-sweetened beverages could reduce consumption by 24 percent, cutting 45 to 50 calories per day from a soda drinker's diet (Preventive Medicine, 2011).
Even with pinching consumers' pocketbooks, though, changing our environment won't be easy. Over the years, the food industry has trained us to snack between meals, gulp down fast food morning and night and expect bottomless soda refills with our vat-sized portions of pasta.
Despite that, Brownell is hopeful. In communities across the country, people are paying more attention to where their food comes from and looking twice at the practices of powerful food companies. "Social norms are beginning to change. People are more concerned than ever about protecting the health of children through nutrition," he says.
Not everyone agrees with such measures, however. Restricting ads aimed at kids raises hackles among many critics on the grounds that doing so impinges on freedom of speech. And plenty of people oppose the government's interference in the free marketplace through taxes or regulations.
Nevertheless, our food environment is beginning to shift, says APA President Johnson. A few years ago, initiatives such as soda taxes seemed impossible, she says. But this fall, the New York City Board of Health approved a ban on the sale of large sodas in restaurants, street carts and movie theaters, a move championed by Mayor Michael Bloomberg. Elsewhere, communities including San Francisco have banned toys in fast-food kids' meals. "I think people are going to start paying attention" to these social experiments, Johnson says. "I'm optimistic, but we have to be very vocal — the folks that are selling the junk are extremely well funded, and very intent on keeping things just the way they are."
Certainly, huge challenges remain. One of the most pressing issues, Wilfley says, is securing reimbursement for professionals who provide obesity treatment. Because most insurance policies don't cover obesity prevention and treatment programs, an overweight child or teenager can't take advantage of such programs unless his or her family is able to pay for it out of pocket.
"The sad part is we can have a much better impact if we treat children at lower levels of overweight," she says. Instead, those kids are overlooked by the health-care system until they develop chronic conditions such as diabetes or cardiovascular disease. "We're waiting for train wrecks," she says.
Another important next step is to move from testing interventions to implementing the ones that work. "There are lots of things going on in communities across the country, and nobody's evaluating them," Foster says. "We have to be thinking about how we can inform policy with data."
In addition to developing and implementing treatments, psychology can do more to promote a healthy, active lifestyle. In 2009, APA endorsed a resolution encouraging psychologists to challenge the disproportionate emphasis on weight reduction and instead apply more energy to helping patients adopt healthier diets and engage in more physical activity.
At the same time, there's still plenty of basic research to be done. Scientists are just beginning to understand food addiction and the ways tempting treats can act like addictive drugs in the brain. Researchers can also contribute to our understanding of what makes certain children vulnerable to obesity, how food becomes rewarding and how parents can help enhance executive functioning and self-control in kids, Epstein says. "Our prevention efforts will be better if we understand more about these basic processes."
Ultimately, experts agree that we need to attack this problem from every possible direction to win our nation's battle of the bulge. And psychologists have something to offer every step of the way.
"Obesity isn't a mental health condition — you won't find it in the DSM-5," says Foster. "But if you believe that psychology is a science of behavior change, then obesity is an optimal condition for leveraging the expertise of psychologists."
Kirsten Weir is a freelance writer in Minneapolis.
APA is appointing a panel of scientists and clinicians to develop clinical treatment guidelines for obesity. The panel will write the guidelines based on systematic reviews of the research literature.
In August, 2012 APA President Suzanne Bennett Johnson, PhD, presented the APA Award for Outstanding Lifetime Contributions to Psychology to two psychologists who have made obesity the cornerstone of their careers. Kelly Brownell, PhD, director of Yale University's Rudd Center for Food Policy and Obesity, has focused on changing public policy to make our eating environments healthier. Rena R. Wing, PhD, professor of psychiatry and behavior at Brown University and director of the Weight Control and Diabetes Research Center at the Miriam Hospital in Providence, R.I., is best known for her work on the Diabetes Prevention Program, a lifestyle intervention proven to help adults shed pounds and prevent the onset of Type 2 diabetes.