Between 2003 and 2006, almost 40% of Mexican-American adolescents (12 to 19) were overweight or likely to become so, according to researchers at the University of Southern California’s Keck School of Medicine.

They found that teens who reduced their daily sugar intake by 47 grams (equal to one can of soda), while increasing their daily fiber intake by 5 grams (equal to one-half cup of beans), lowered their risk of developing type 2 diabetes.

Emily Ventura, MPH, and her colleagues in the Department of Preventive Medicine published their results in the April edition of Archives of Pediatrics & Adolescent Medicine.

Teens who decreased their sugar intake secreted 33% less insulin, while those who increased their fiber intake lost 10% of fat around vital organs. Insulin resistance and obesity are two major risk factors for diabetes.

“Our results suggest that intensive interventions may not be necessary to achieve modifications in sugar and fiber intake,” the authors write. “Accordingly, nutritional guidance given in the primary-care or community setting may be sufficient to promote the suggested dietary changes in some individuals. In addition, policies that promote reduced intake of added sugar and increased intake of fiber could be effective public-health strategies for the prevention of type 2 diabetes in this high-risk population.”

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