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USC study searches for nutritional sweet-spot for teen girls’ sugar intake

Michael GoranPhoto/Jon Nalick

Girls may be made of sugar and spice and everything nice — but today, they might be consuming a little too much sugar for their own good.

Obesity researcher Michael I. Goran, professor of preventive medicine at the Keck School of Medicine, said sugary foods are making up a growing chunk of kids’ daily diet. So he and his colleagues, research associate Jaimie Davis and research assistant Emily Ventura, are conducting a two-year study in teen-age girls on the effect of a program that lowers their sugar consumption—in exchange for foods higher in fiber and complex carbohydrates.

The study will evaluate how dietary carbohydrates affect obesity and risk factors for diabetes, such as insulin values.

“Kids today are getting too much of their caloric intake from sugar,” said Goran, associate director of the USC Institute for Health Promotion and Disease Prevention Research. “We’re working on ways to replace that sugar with fiber and more complex carbohydrates that have nutritional value.”

About 40 overweight teen-age Latinas in the Los Angeles area will be enrolled in the study. They will complete questionnaires about their diet and will work with a nutrition educator, who will help them adopt healthier eating habits. Researchers will evaluate weight and insulin values throughout the pilot study. They also will test a new 12-week curriculum they developed, comparing its effectiveness in a class setting against its delivery through an individual nutrition coach.

Such efforts are becoming more important as researchers come to recognize the relationships between changing eating habits and chronic illness.

Worldwide, the average person in the late 1990s ate 450 calories a day more than in the mid-1960s, according to the World Health Organization (WHO). In industrialized countries, such as the United States, caloric intake grew by about 430 calories a day during these 40 years. Other research shows that Americans got 83 more calories a day from sugary sweeteners (such as glucose, high-fructose corn syrup and sucrose) in 2000 than in 1962. That means sugary foods comprise 16 percent of Americans’ daily calories (up from 13 percent in 1962).

Among Latino children, research shows that about 20 percent of calories are consumed as sugar—twice the WHO’s recommendation of 10 percent. Much of the sugar consumption comes from sugary beverages; Latino children in Los Angeles consume about two to three sugary beverages a day, Goran said.

Consuming more calories contributes to obesity, which has been implicated in a number of diseases. But high consumption of refined sugars specifically also has health researchers concerned.

Eating more processed sugary foods at the cost of unprocessed foods rich in complex carbohydrates—such as whole grains, vegetables and beans—has been implicated in diseases such as type 2 diabetes and colon cancer, for example.

Research by Goran’s group explores links to type 2 diabetes, a chronic disease that is affecting Americans in increasing numbers and at earlier ages—even in adolescence.

Type 2 diabetes is characterized by a decline in how well the pancreas’ beta cells (the body’s factories for insulin) function. Based on some initial findings, Goran and colleagues suspect that children who eat more sugar have lower beta cell function.

Goran notes that lowering refined sugars and eating more complex carbohydrates, such as fiber, can lead to eating fewer calories overall. “If you’re eating more fiber instead of sugar, you’ll feel more full, and you’ll eat less,” he said. “It’s a subtle effect, but over time, it would make a difference.”

Ultimately, Goran hopes to combine a carbohydrate-modification diet strategy with his other intervention project, which involves strength training exercise. Goran and his colleagues have been testing strength training—or lifting weights—as a way to increase Latino teen-age boys’ sensitivity to insulin and lower their risk for type 2 diabetes.

The study is funded by the The Dr. Robert C. Atkins Foundation, which supports research in the use of controlled carbohydrates in disease prevention and treatment.

USC study searches for nutritional sweet-spot for teen girls’ sugar intake

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