* Half of all Americans will be obese by 2030 - report
* More companies vowing to take steps to address kids' weight
* Access to healthier foods increasing, group says
By Susan Heavey
WASHINGTON, March 7 (Reuters) - U.S. companies and other groups that have made attempts to reverse the nation's rising childhood obesity rate are starting to see results as more American kids exercise and have better access to healthy foods, they said on Thursday.
More than 1,700 U.S. cities have promoted exercise to get nearly 3 million more kids moving in the last year, according to a report by the Partnership for a Healthier America, a nonprofit that works to get private companies and organizations to pledge specific action to fight the weight epidemic.
Still, if left unchecked, about half of all Americans will be obese by 2030, according to the group, whose partners range from Darden Restaurants Inc and Walmart Stores Inc to the YMCA and the U.S. Olympic Committee.
Some health advocates welcomed the findings but said more effort was still needed, including government action.
Already, one in three U.S. youth are obese and another third are overweight. Experts are worried because heavier children are more likely to remain overweight as adults, and suffer a higher incidence of diabetes, heart disease and other conditions.
"We're seeing pockets of progress toward reversing the childhood obesity epidemic," said Dr. Risa Lavizzo-Mourey of the Robert Wood Johnson Foundation. "For progress to reach every corner of our country, we must redouble our efforts: parents, schools, nonprofit organizations, government at all levels, and the private sector."
Childhood obesity carries significant healthcare related costs and even poses national security risks, experts say, by reducing the pool of those fit for military service.
Some of the partner companies have pledged to change food offerings on restaurant menus or work to get more children into activities like soccer or tennis, according to the group, which released the report as part of its annual conference in Washington that also headlined First Lady Michelle Obama.
The group has said it wants to help 10 million Americans gain access to healthier foods, saying 23.5 million people in the United States - including 6.5 million children - have no nearby access to options like fresh produce or cannot afford to buy it.
Already, 141 grocery stores have been built or renovated in so-called "food deserts," often low-income urban neighborhoods without nearby grocery stores, helping more than a half-million people, it said.
"In places like Philadelphia, New York City and Mississippi - places where folks from every sector are working together - we've seen childhood obesity rates begin to come down," said Obama, who has made tackling obesity her signature issue while in the White House.
Fruits and vegetables, meat and other whole foods can often be more expensive than processed ones that contain subsidized ingredients such as high fructose corn syrup.
Some health experts have been critical of the food industry for offering unhealthy products. Manufacturers have long pointed to consumer choice, but many have begun to change their offerings in recent years as more U.S. consumers become health conscious.
Newark, New Jersey Mayor Cory Booker, another honorary vice chairman and a Democrat, told MSNBC the annual progress report is important for holding companies accountable to their commitments to change.
On Thursday, several more companies joined the partnership, including GE Healthcare, part of General Electric Co, and Cerner Corp, among others.