Obesity in the United States is projected to continue its rise over the next 18 years, extending to 42% of Americans by 2030, according to a study released Monday by the Centers for Disease Control and Prevention. 
 
 That expected growth in the proportion of obese Americans -- up from 34% -- contained good news and bad: Obesity's growth has slowed from the record-setting pace that has marked most of the last three decades; at the same time, the numbers of the severely obese -- those carrying 80 or more pounds more than the healthy, normal weight for their height -- is expected to grow by 130%. 
 
 The continued growth in obesity will be expensive, said CDC statisticians: Additional spending on healthcare for Americans who will join the ranks of the obese in the next 18 years was projected to reach $549.5 billion over the next two decades. 
 
 By the most current obesity statistics, 35.7% of American adults -- 78 million people -- and 16.9% of U.S. children and adolescents -- 12.5 million kids -- are obese, meaning their body-mass index is 30 or over. 
 
 The new projections capture several trends in American society: the swelling population of Latino adults, among whom obesity is a growing problem, the transition into adulthood of a population of obese children -- especially African American boys -- who stand a high likelihood of becoming obese adults, and the aging of overweight and obese adults, who are far more likely to take on more weight than to lose as they get older. 
 
 In a bit of good news, the obesity rate among women was flat. Currently, 35.8% of American women are considered obese, and the forecast released Monday does not predict a significant change in that level. 
 
 Still, the projected 33% rise in obesity is rosier than the 51% rise that had been projected by statisticians assuming a continued level of the roaring growth seen in the 1980s, 1990s and early 2000s. "This and other forecasts likely overstate future obesity prevalence given the recent evidence of slower growth," wrote Duke University global health professor Eric A. Finkelstein and co-authors in a forecast of the nation's weight problem close to 20 years out. 
 
 In a news conference that was the centerpiece of a second annual "Weight of the Nation" conference in Washington, D.C., Finkelstein said it was unclear whether the galloping rate of growth has slowed because of public policy initiatives aimed at preventing child obesity, greater societal awareness of obesity's risks, or because Americans have hit the maximum level of fatness a population can sustain. 
 
 "The slope has changed," he said. Statistically, he noted, "it doesn't take much" for obesity prevalence to rise from 34% to 42% in 18 years. 
 
 By the same logic, the authors of the projection noted that even small successes in anti-obesity efforts -- new, more effective weight-loss drugs, communities and campaigns designed to encourage more exercise and healthier eating, work-site health-promotion policies -- could flatten the upward curve. 
 
 "Even small improvements in obesity prevalence ... could result in substantial savings," they added. The projected $549.5-billion healthcare bill represents the difference between providing healthcare for a population with 34% obesity and a population whose obesity prevalence has risen to 42%. 
 
 The CDC forecast took into account a host of factors thought to influence Americans' eating and exercise habits, including the cost of groceries, the density of restaurants, rates of unemployment, Internet access and the price of gas. Most important, however, was the aging of the population, which tends to nudge many overweight adults into the obese category, and to push a growing number of those who are already obese into "severely obese" territory. 
 
 "Long-term, sustained weight loss" in adults who have become obese, said Finkelstein, "is elusive." 
 
 Finkelstein and his co-author, health economist Justin G. Trogdon of RTI International, cautioned that despite their detailed modeling of factors that influence obesity, forecasting fatness in a future population "is tricky business." While tendency to exercise, access to healthy food and convenience of high-calorie fast food all influence a population's propensity to gain weight, such factors stand alongside far more powerful influences, such as genetics. 
 
 "They're estimates, but like any estimates, are they going to be accurate?" Finkelstein asked Monday. "Well, time will tell." ||||| If waistlines keep expanding at current rates, half of the U.S. population will be obese by 2030, according to a new report. 
 
 The current trajectory, according to a two-decade trend of steady weight gain, would see 65 million more obese adults, raising the national total to 164 million. Roughly one-third of the U.S. population is currently obese. 
 
 "At the rate we're looking at right now, it's a dire prediction," said Claire Wang, assistant professor of health policy and management at Columbia University's Mailman School of Public Health and lead author of the study that was published in the Lancet. "Something has to be done." 
 
 The rise in obesity could lead to 7.8 million more cases of diabetes, 6.8 million cases of heart disease and stroke, and more than half a million extra cancer cases in the U.S. -- all of which would balloon health care costs by $66 billion a year, according to the report. 
 
 "It's not only a problem of well-being, it's a financial burden," said Wang. "It's both a public health issue and a health services issue for the states." 
 
 But if every obese person decreased his or her body mass index by just 1 percent (a loss of 2 pounds for a 200-pound adult), as many as 2.4 million diabetes cases, 1.7 million cases of heart disease and stroke and 127,000 cancer cases could be prevented. 
 
 "We hope we can work together to change the trend," said Wang, adding that solutions have to come from individuals, communities and the government. "We need to change the environment so that we're able to make easy decisions that happen to be the best decisions; the healthiest decisions." 
 
 The need for effective, cost-effective solutions is particularly pressing as obese baby boomers move into older age. 
 
 "Excess body weight combined with older age is going to lead to an expansion of chronic conditions," said Wang, describing weight's link to such age-related conditions as arthritis. "Our health care system is already struggling with resource constraints." 
 
 Obese America Stretching Resources Thin 
 
 Dr. Ken Fujioka, director of the Center for Weight Management at the Scripps Clinic in San Diego, said ever-growing waitlists for obesity clinics are already three months long. 
 
 "We're having trouble keeping up," said Fujioka, adding that roughly half of patients referred to his clinic are morbidly obese. "On the front lines, it's just frightening." 
 
 Obesity treatments, such as bariatric surgery, are effective, but many patients are reluctant to undergo such an invasive procedure. And a dearth of drugs approved to treat obesity leaves few options for extreme weight loss short of strict diets and intense exercise programs. 
 
 For now, Fujioka said solutions should focus on prevention. Taxes on unhealthy foods that provide empty calories, like sugary sodas, could help curb consumption and provide revenue for public policy changes, he said. 
 
 "Many schools are having to cut down on physical education because of budget constraints," he said. "That is a huge mistake, not being able to get our kids to exercise." 
 
 But changes have to come at the family and individual level, too. Buying a bathroom scale can help people stay on top of their weight and monitor small changes. Cutting down on TV time and ramping up regular physical exercise -- even a walk -- can help balance calories consumed and spent. And limiting access to junk food can make it easier to make healthy choices. 
 
 "Policies are great, but we can't wait for them," said Keith Ayoob, director of the Rose R. Kennedy Center Nutrition Clinic at Albert Einstein College of Medicine in New York. If you look at people who lose weight, they tend to eat a fairly low-fat diet. They eat breakfast every day, and most of them have committed to doing a little bit of exercise." 
 
 One glum prediction that wasn't captured in the study is the fate of the 17 percent of U.S. teens who are obese. 
 
 "We've not yet been able to observe the full impact of childhood obesity," said Wang, pointing out that type 2 diabetes, once called adult onset diabetes, is now showing up in teens. "Intervening at an early age and in the early stage of the weight gain trajectory is going to be so important." 
 
 Ayoob blames inactivity for the rise in childhood obesity. 
 
 "When I was a kid, kids drank whole milk and ate junk food whenever they could get it. But we moved," he said, describing the eagerness to get outside and play. "Nowadays kids don't do that. They only leave the house to get to someone else's house to play video games."
– The once-explosive growth in the proportion of Americans who are obese has slowed, but it's still expected to grow to 42% by 2030, according to the latest Centers for Disease Control study. The study found that if the obesity rate stays at the current level—34%—then some $550 billion in health care costs would be saved, reports the Washington Post. Earlier studies predicted that 51% of Americans would be obese by 2030, but no matter which is correct, "we still have a very serious problem," the head of the CDC's obesity program says. The obesity rate among women has stayed flat, but other groups, including higher-income men, are continuing to put on weight, and more obese people are becoming severely obese, according to the study, which predicts that the aging of the population will probably nudge many overweight adults into the obese category, and obese people into severely obese. The study's authors say it's not clear whether the growth in obesity has slowed somewhat because of the success of public policy initiatives, or because the US is nearing the maximum level of obesity that a population can sustain, notes the Los Angeles Times.