American Diet Quality: Where It Is, Where It Is Heading, and What It Could Be.

BACKGROUND
Diet quality is critically important to the prevention of many types of chronic disease. The federal government provides recommendations for optimal diet quality through the Dietary Guidelines for Americans, and sets benchmarks for progress toward these recommendations through the Healthy People objectives.

OBJECTIVE
This analysis estimated recent trends in American diet quality and compared those trends to the quality of diets that would meet the Healthy People 2020 objectives and the 2010 Dietary Guidelines for Americans in order to measure progress toward our national nutrition goals.

DESIGN
This analysis used 24-hour recall data from the cross-sectional National Health and Nutrition Examination Survey, between the years of 1999-2000 and 2011-2012, to determine mean intakes of various dietary components for the US population over time. Mean intakes were estimated using the population ratio method, and diet quality was assessed using the Healthy Eating Index 2010 (HEI-2010).

RESULTS
The mean HEI-2010 total score for the US population has increased from 49 in 1999-2000 to 59 in 2011-2012; continuing on that trajectory, it would reach a score of 65 by 2019-2020. A diet that meets the Healthy People 2020 objectives would receive a score of 74 and, by definition, a diet that meets the 2010 Dietary Guidelines for Americans would receive a score of 100. Trends in HEI-2010 component scores vary; all HEI-2010 component scores except sodium have increased over time.

CONCLUSIONS
Diet quality is improving over time, but not quickly enough to meet all of the Healthy People 2020 objectives. Whole fruit and empty calories are the only HEI-2010 components on track to meet their respective Healthy People 2020 targets. Furthermore, the country falls short of the 2010 Dietary Guidelines for Americans by a large margin in nearly every component of diet quality assessed by the HEI-2010.