School vending machines and cafeterias will no longer sell soda or other sugary soft drinks under regulations approved Wednesday by the Colorado Board of Education.

High school students will still be allowed to buy low-calorie sport drinks. But board members specifically barred diet soda.

"If they're allowed diet soda, kids get in the habit of drinking soda," said board member Evie Hudak.

The rules take effect July 1, 2009, or when a school district completes its contract with a distributor.

The board vote was unanimous, following testimony by parents and medical experts who said only healthy choices should be available in schools.

"When all the bad choices are available at school, it undercuts parents' ability to guide their children through the fast food and drink minefield," said Phyllis Albritton, an Evergreen parent who is active in the Jefferson County PTA.

The legislature last spring adopted a bill barring all but healthy beverages in schools, but directed the board to decide which drinks to allow. The bill was intended to reduce childhood obesity.

The board vote permits water, low-fat milk, low-fat flavored milk, milk substitutes approved by the U.S. Department of Agriculture and juice in elementary and middle schools.

High school students can buy the same items, but in larger portions, plus low-calorie sport drinks and other unspecified low-calorie beverages.

An amendment to bar diet soda passed unanimously.

Bruce Caughey of the Colorado Association of School Executives, the group that includes school superintendents, said he believes most districts were are on their way to eliminating unhealthy beverages. He wasn't sure if the districts were eliminating diet soda.

University of Colorado dental school professor Paul Bottone warned that many of the chemicals listed on diet sodas could prove harmful.

Pediatrician Sandy Stenmark said federal agencies have determined that artificial sweeteners in diet soda are not harmful. But she doesn't drink them or serve them to her children, Stenmark said.

"The healthiest beverages are water and low-fat milk. If you wanted to do what was healthiest for the children, those would be the only beverages you would allow in schools," Stenmark said.

Stenmark said fruit juice is high in calories and vegetable juice is high in sodium.

Board president Pamela Jo Suckla voted for the rules "under duress." She believes parents should determine what their children drink, but bowed to the legsilative directive that the board pass rules.

Board member Elaine Gantz Berman said the rule is needed.

"I am paying for the health care of diabetic children. I am paying for the health care of obese children," Berman said.

She added, "I don't drink artificial sweeteners in anything."