With millions of children and adolescents are overweight or obese and the risks for many chronic diseases increasing, a study of childrens' diets has revealed some disturbing truths.
"The epidemic of obesity among children and adolescents is now widely regarded as one of the most important public health problems, especially in the US," said Jill Reedy, PhD, MPH, RD, and Susan M. Krebs-Smith, PhD, MPH, RD, both of the Division of Cancer Control and Population Sciences, National Cancer Institute.
"Most experts agree that the solution will involve changes in both diet and physical activity, in order to affect energy balance. For diet, this means a reduction in energy from current consumption levels…This paper identifies the major sources of overall energy and empty kilojoules, providing context for dietary guidance that could specifically focus on limiting kilojoules from these sources and for changes in the food environment.
"Product reformulation alone is not sufficient - the flow of empty kilojoules into the food supply must be reduced."
For two to 18 year olds, the top sources of energy were grain desserts, pizza, and sodas. Sugar-sweetened beverages (sodas and fruit drinks combined) provided almost 10% of total kilojoules consumed. Nearly 40% of total kilojoules consumed by two to18 year olds were in the form of empty kilojoules from solid fat and from added sugars.
Half of empty kilojoules came from six foods: soda, fruit drinks, dairy desserts, grain desserts, pizza, and whole milk.
Researchers examined data from the National Health and Nutrition Examination Survey (NHANES), a nationally representative survey with a complex multistage, stratified probability sample.
Trained interviewers conducted in-person 24-hour dietary recalls with all eligible persons, using automated data collection systems that included multiple passes. Kilojoules from solid fats and added sugars were calculated from the USDA MyPyramid Equivalents Database (MPED).
Empty kilojoules were defined as the sum of energy from solid fats and added sugars.
Sugar-sweetened drinks and obesity
Children of different ages get their energy from different sources. For example, the top five sources of energy for two to three year olds included whole milk, fruit juice, reduced-fat milk, and pasta and pasta dishes.
Pasta and reduced-fat milk were also among the top five sources of energy for four to eight year olds. Top contributors of energy also varied by race/ethnicity.
In an accompanying commentary, Rae-Ellen W. Kavey, MD, MPH, University of Rochester Medical Center, Department of Paediatrics, Division of Cardiology, Rochester, NY, discusses the role of sugar-sweetened beverages in the development of obesity in childhood.
Dr Kavey writes, "High added sugar consumption which occurs most commonly in the form of sugar-sweetened beverages is associated with a constellation of cardiovascular risk factors, both independently, and through the development of obesity. Multiple studies have shown that presence of these risk factors in childhood is associated with accelerated atherosclerosis and early cardiovascular disease.
Reduce sugary drinks, reduce heart risks
"Randomised trials of nutritionist-guided interventions show us that diet change can be accomplished and is associated with important cardiovascular benefits. This combined body of evidence suggests that reducing consumption of sugar-sweetened beverages should be considered a critical dietary approach to reducing cardiovascular risk in childhood."
A study of how school vending machines can influence the dietary choices of students is presented in the same issue.
Researchers from the CDC and the Florida Department of Health found that the availability of vending machines in schools was associated with buying snacks or beverages from vending machines instead of buying school lunches.
They also found that although healthier choices were available in school vending machines, the most common choices by students were less healthy snacks and beverages. - (EurekAlert, October 2010)