More than one-third of U.S. adults (35.7 percent) are obese today and 17 percent of children are obese. A health group warned in a report Thursday that if American's don't start eating healthier and getting more exercise, half of the nation will be obese by 2030.

Partnership for a Healthier America, a nonprofit that collaborates with private companies and organizations to garner support and take action against the weight epidemic, said children especially need to be of concern. Heavier children are more likely to remain overweight as adults, and suffer a higher incidence of diabetes, heart disease and other conditions.

"It's an epidemic," said Frist, noting obesity was not a problem 30 years ago.

"Right now one in four of our young kids ages 17 to 24, military age," adds Booker, "don't qualify to serve in the military."

Childhood obesity comes with greater healthcare related costs and even poses national security risks, experts say, by lowering the amount of citizens physically fit to serve their country in the military.

However, it's not all bad news. The report showed that 1,700 U.S. cities have promoted exercise to get nearly 3 million more kids active in the last year, according to Reuters.

The group also noted it has helped 10 million Americans gain access to healthier foods. However, 23.5 million people in the United States - including 6.5 million children - still have no nearby access to options like fresh produce or cannot afford to buy it.

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