By Lisa Baertlein

Feb 13 (Reuters) - Anti-obesity advocates who want to curb Americans' sugar habit on Wednesday asked the government to set a safe level for added sugars in soda and other beverages.

The Center for Science in the Public Interest (CSPI), which is leading the regulatory push, has urged the government to take actions to reduce Americans' sugar consumption since the 1970s.

The consumer group's 54-page regulatory petition filed with the Food and Drug Administration on Wednesday is part of a broad public health campaign to trim waistlines in the United States, where more than two-thirds of adults and nearly one-third of children aged 2 to 19 are overweight or obese.

Sugar-sweetened drinks are a significant source of extra calories in the U.S. diet and are closely linked with weight gain, which often accompanies serious and costly illness such as diabetes and heart disease.

If history holds true, the latest request will not result in swift action from the FDA. The American Beverage Association (ABA) and other industry groups have aggressively, and often successfully, fought efforts to reduce sugary drink consumption via regulation or taxes. They say the industry is being unfairly blamed for the nation's obesity crisis.

"Everyone has a role to play in reducing obesity levels - a fact completely ignored in this petition," ABA said in a statement.

CSPI Executive Director Michael Jacobson, hopes Wednesday's action will force soda makers to more aggressively change over to lower-calorie drinks.

"As currently formulated, Coke, Pepsi, and other sugar-based drinks are unsafe for regular human consumption," Jacobson said. "The FDA should require the beverage industry to re-engineer their sugary products over several years, making them safer for people to consume, and less conducive to disease."

TOO MUCH SWEET STUFF

Americans, on average, consume 18 to 23 teaspoons of added sugars each day, according to data from National Health and Nutrition Examination Survey and the U.S. Department of Agriculture. That's 300 to 400 calories worth of added sugars daily, significantly more than experts consider healthy.

The American Heart Association advises consuming no more than six teaspoons of added sugars per day for women and no more than nine teaspoons for men.

A typical 20-ounce bottle of soda contains about 16 teaspoons of sugars, often from high-fructose corn syrup.

A Tufts University review of studies published over 17 years found that consumption of sugar-sweetened beverages was the most consistent dietary factor associated with weight gain.

The ABA, the soda industry group, challenges such links, saying obesity rates have risen even as U.S. consumption of full-calorie sodas has declined.

During the 1990s regular soft drinks were the No. 1 source of added sugars and the greatest single contributor of calories in the U.S. diet. Those beverages now account for 41 percent of added sugar calories versus 59 percent for foods, according to a National Center for Health Statistics March 2012 data brief.

Americans on average drink 44.6 gallons of soft drinks each year, down from a peak of 54 gallons in 1998, according to Beverage Digest. Diet drinks, water and teas currently account for a bigger portion of the soda industry's sales than sugary drinks, driving a decline in the overall intake of added sugars.

CSPI and its supporters, which include dozens of scientists, doctors and public health departments, hope to convince the beverage companies to make an even bigger shift to low-calorie sugar substitutes.

FDA classifies high-fructose corn syrup and other sugars as "generally recognized as safe." That classification is based on scientific consensus that the ingredient is not harmful under the intended conditions of use.

Scientific consensus is that added sugars are unsafe at current consumption levels, CSPI said.

CSPI's petition asks FDA, which oversees most food products, to set a safe level for added sugars in beverages and to require that the limits be phased in over several years.

FDA said it received the petition and will respond to CSPI.

PLAYING THE LONG GAME

CSPI has made similar FDA requests before.

The nonprofit sued the agency in 2005 for failing to set sodium limits for food - a move health experts say would help save thousands of lives each year. FDA has not yet set such limits, but food makers have lowered sodium in some products with varying degrees of success.

CSPI scored a victory, though it took years, when FDA required that artery-clogging artificial trans fat be included in food labels starting in 2006. That effort, along with state and city trans fat bans, resulted an a sharp decline in use.

"The lesson from these things is that it takes forever to move things in Washington," CSPI's Jacobson said.

Public health campaigners have a mixed record when it comes to other efforts to cut the consumption of sugary drinks.

In 2006, after a long battle, Coca-Cola Co, PepsiCo Inc and Dr. Pepper Snapper Group Inc surrendered to pressure and agreed to remove high-calorie sodas from U.S. public schools. Front-of-package calorie labels followed.

New York City Mayor Michael Bloomberg's first-of-its-kind ban on super sized sugary drinks in restaurants and other eateries is scheduled to start in March. Industry is challenging the ban, calling it an unconstitutional overreach that burdens small businesses and infringes upon personal liberty.

The soft drink industry has a strong record of defeating high-profile efforts to tax sugary beverages, and two separate ballot measures recently fizzled in California.

It also has waged its own public relations campaign. Coca-Cola this year aired commercials on U.S. cable television highlighting its obesity-fighting efforts. 

(Additional reporting by Adam Kerlin)

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