New research shows that the more added sugar kids get from sodas, sweets and fruit drinks, the less they get of the things they need in their diets to stay healthy.

U.S. investigators found that preschoolers who obtained a higher percentage of their daily calories from added sugars tended to get fewer calories from healthier sources, including foods rich in fiber, vitamins and minerals.

Study author Dr. Sibylle Kranz explained that kids have an "internal control" system in their bodies that limits their intake of calories, so they typically eat the same number of calories, regardless of the source. "If a child drinks a regular soda, for example, that drink is replacing another potentially high-nutrient food," she stated.

It's important for kids to get the vast majority of their calories from foods rich in vitamins and minerals, she noted.

"Since most foods that are high in added sugar have very low nutrient density -- very little vitamins and minerals -- they contribute calories but not the important micronutrients for health and growth," said Kranz, who is based at Pennsylvania State University in State College.

Kranz noted that "added" sugars are not the same as sugars naturally found in foods like fruits and dairy. Added sugars are included during baking or manufacturing, and are primarily found in sodas, fruit drinks, desserts and candy, she said.

In an article in the January issue of the Journal of Pediatrics, Kranz and her colleagues explain that the U.S. food guide pyramid currently recommends that kids limit added sugars to between six and 10 percent of their total calories, and the World Health Organization has limited added sugars to less than 10 percent of total calories. However, the National Academy of Sciences recently said that it's okay for people to get up to 25 percent of their total calories from added sugar.

These recommendations matter, the authors note, in part because they are often used to help determine federal nutrition programs.

To investigate how kids' diets fare with different amounts of added sugar, Kranz and her team reviewed the diets of 5,437 children between the ages of two and five, noting how much added sugar they ate and what they consumed in important nutrients.

The study found that the more added sugar kids ate, the less they got of fiber, protein, calcium, iron, folate and other key nutrients.

Most children got less than 25 percent of their daily calories from added sugar, but those who got at least 25 percent from added sugars ate the smallest amounts of grains, vegetables, fruits and dairy.

Younger children typically ate less added sugar than older children, the authors note. Among two-year-olds and three-year-olds, average consumption of added sugar was about 14 teaspoons per day, relative to an average of about 17 daily teaspoons among four-year-olds and five-year-olds.

Although it's not clear what amount of added sugar is okay for kids, these findings suggest that the National Academy of Sciences' cutoff of 25 percent of daily calories may be too high, Kranz argued. "Based on our results, we are concerned that at the (recommended) level of added sugar intake, children do not have adequate intake of vitamins and minerals important for their health and growth," she said.

SOURCE: The Journal of Pediatrics, January 2005.