In an ambitious 478-page report, the IOM refutes the idea that obesity is largely the result of a lack of willpower on the part of individuals. Instead, it embraces policy proposals that have met with stiff resistance from the food industry and lawmakers, arguing that multiple strategies will be needed to make the U.S. environment less "obesogenic."

The IOM, part of the Washington-based National Academies, offers advice to the government and others on health issues. Its report was released at the Weight of the Nation conference, a three-day meeting hosted by the U.S. Centers for Disease Control and Prevention. Cable channel HBO will air a documentary of the same name next week.

"People have heard the advice to eat less and move more for years, and during that time a large number of Americans have become obese," IOM committee member Shiriki Kumanyika of the University of Pennsylvania School of Medicine told Reuters. "That advice will never be out of date. But when you see the increase in obesity you ask, what changed? And the answer is, the environment. The average person cannot maintain a healthy weight in this obesity-promoting environment."

Shortly after the report was released, the Center for Consumer Freedom, which is funded by restaurant, food and other industries, condemned the IOM as joining forces with the nation's "food nannies." The Center said the IOM recommendations would "actively reduce the number of choices Americans have when they sit down to eat" and emphasized that "personal responsibility" alone was to blame for the obesity epidemic.

A study funded by the CDC and released on Monday projected that by 2030, 42 percent of American adults will be obese, compared to 34 percent now, and 11 percent will be severely obese, compared to the current 6 percent.

Another one-third of American adults are overweight, and one-third of children aged 2 to 19 are overweight or obese. Obesity is defined as having a body mass index - a measure of height to weight - of 30 or greater. Overweight means a BMI of 25 to 29.9.

Officials at the IOM and CDC are trying to address the societal factors that led the percentage of obese adults to more than double since 1980, when 15 percent were in that category. Among children, it has soared to 17 percent from 5 percent in the past 30 years. One reason: in 1977, children 2 to 18 consumed an average of 1,842 calories per day. By 2006, that had climbed to 2,022.

Obesity is responsible for an additional $190 billion a year in healthcare costs, or one-fifth of all healthcare spending, Reuters reported last month, plus billions more in higher health insurance premiums, lost productivity and absenteeism.

NO MAGIC BULLET

The IOM panel included members from academia, government, and the private sector. It scrutinized some 800 programs and interventions to identify those that can significantly reduce the incidence of obesity within 10 years.

"There has been a tendency to look for a single solution, like putting a big tax on soda or banning marketing (of unhealthy food) to children," panel chairman Dan Glickman, a senior fellow of the Bipartisan Policy Center and a former secretary of the Department of Agriculture, told Reuters. "What this report says is this is not a one-solution problem."

The panel identifies taxing sugar-sweetened beverages as a "potential action," noting that "their link to obesity is stronger than that observed for any other food or beverage."

A 2011 study estimated that a penny-per-ounce tax could reduce per capita consumption by 24 percent. As a Reuters report described last month, vigorous lobbying by the soda industry crushed recent efforts to impose such a tax in several states, including New York.

"I do not think in any way, shape or form that such punitive measures will change behaviors," said Rhona Applebaum, Coca-Cola Co.'s chief scientific and regulatory officer, in advance of the report. Anyone deterred by the tax from buying sweetened soda, she said, will replace those calories with something else.

The IOM committee also grappled with one of the third rails of American politics: farm policy. Price-support programs for wheat, cotton and other commodity crops prohibit participating farmers from planting fruits and vegetables on land enrolled in those programs. Partly as a result, U.S. farms do not produce enough fresh produce for all Americans to eat the recommended amounts, and the IOM panel calls for removing that ban.

The committee did not endorse the call by food activist Michael Pollan and others to eliminate farm subsidies that make high-fructose corn syrup, partially hydrogenated vegetable oils and other obesity-promoting foods very cheap. "There is no evidence subsidies contribute to obesity," said Glickman.

THE TRUE LACK OF CHOICE

The traditional view that blames obesity on a failure of personal responsibility and individual willpower "has been used as the basis for resisting government efforts - legislative and regulatory - to address the problem," says the report. But the IOM panel argues that people cannot truly exercise "personal choice" because their options are severely limited, and "biased toward the unhealthy end of the continuum."

For instance, a lack of sidewalks makes it impossible to safely walk to work, school or even neighbors' homes in many communities. So while 20 percent of trips between school and home among kids 5 to 15 were on foot in 1977, that figure had dropped to 12.5 percent by 2001.

The panel recommended tax incentives for developers to build sidewalks and trails in new housing developments, zoning changes to require pedestrian access and policies to promote bicycle commuting. Flexible financing, and streamlined permitting or tax credits could be used as encouragement.

The IOM report also calls for making schools the focus of anti-obesity efforts, since preventing obesity at a young age is easier than reversing it. According to the most recent data, only 4 percent of elementary schools, 8 percent of middle schools and 2 percent of high schools provided daily physical education for all students.

The IOM report recommends requiring primary and secondary schools to have at least 60 minutes of physical education and activity each day. It calls for banning sugar-sweetened drinks in schools and making drinking water freely available.

The report also urges that healthy food and drinks be easily available everywhere Americans eat, from shopping centers to sports facilities and chain restaurants. The idea is that more people will eat healthier if little active choice is needed.

"We've taken fat and sugar, put it in everything everywhere, and made it socially acceptable to eat all the time," David Kessler, former head of the U.S. Food and Drug Administration, told Reuters. He was not part of the IOM panel.

"We're living in a food carnival, constantly bombarded by food cues, almost all of them unhealthy," Kessler said.

Experience has shown that when businesses offer consumers a full range of choices - and especially when the healthy option is the default - many customers will opt for salads over deep-fried everything.

Walt Disney Co., for instance, found more than 50 percent of customers accepted a healthier choice of foods introduced at its theme parks. And last summer, fast-food giant McDonald's Corp said it would include apples, fewer fries, and 20 percent fewer calories in the most popular Happy Meals for kids.

The IOM report urges employers and insurers to do more to combat obesity. UnitedHealth Group offers a health insurance plan in which a $5,000 yearly deductible can be reduced to $1,000 if a person is not obese and does not smoke. Some employers provide discounts on premiums for completing weight-loss programs.

Such inducements are far from universal, however. The government-run Medicaid healthcare program for the poor and disabled does not cover weight-loss programs in many states. And as of 2008, only 28 percent of full-time workers in the private sector and 54 percent in government had access to wellness programs.

(Editing by Michele Gershberg, Christopher Wilson and Paul Simao)

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