Public health advocates are lobbying for limits on the availability of sports drinks such as Gatorade and Powerade in high school vending machines.

They say the drinks contain more sodium and as much as two-thirds the sugar of sodas, The Washington Post reported Monday. Lobbyists representing major soft drink bottlers say sports drinks are essential to young athletes.

A report from the University of California at Berkeley, however, said students who drink a 20-ounce sports drink every day for a year may gain about 13 pounds, the newspaper said.

"For years we've been programmed to believe that sports drinks are healthy and you need to replenish those electrolytes after you go out and walk the dog," Margo Wootan, director of nutrition policy at the Center for Science in the Public Interest, told the Post.

The limits could become part of a bill introduced by Sen. Tom Harkin, D-Iowa, that would allow the federal government to set new nutritional standards for the foods and drinks sold outside school cafeterias.

Copyright 2007 by United Press International