The Reporting of "What We Eat in America" Nutrient Intake Data in the Scientific Literature: A Scoping Review.

Background: The U.S. national dietary surveillance program, What We Eat in America (WWEIA), National Health and Examination Survey (NHANES), quantifies intake of nutrients, food, and other components across ages and life stages for the non-institutionalized population of the United States. The use of this continuously collected, nationally representative, publicly available data has never been quantified.

Objective: To determine the extent to which nutrient data from WWEIA, NHANES are reported in the peer-reviewed, scientific literature.

Methods: Scientific studies were identified using searches in MEDLINE, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials. Inclusion criteria required studies to be peer-reviewed, published in English between 2013 and 2023, and report one or more nutrients using WWEIA, NHANES data from any cycle of the continuous NHANES (1999-2020). Screening and data extraction were conducted by two independent reviewers, with conflict resolution by a third reviewer.

Results: Of 12,589 screened studies, 2,203 met the inclusion criteria. The number of included studies by publication year increased nearly fourfold over the study period and were authored by researchers located in 60 countries. The most frequently reported nutrients were energy (n=1,724; 78%), total saturated fatty acids (n=918; 42%), sodium (n=828; 38%), protein (n=748; 34%), total polyunsaturated fatty acids (n=745; 34%), total monounsaturated fatty acids (n=702; 32%), dietary fiber (n=707; 32%), total fat (n=682; 31%), and carbohydrates (n=598; 27%). Fifty-seven percent of studies (n=1,266) reported at least one mineral, and 35% (n=771) at least one vitamin. Nearly one-third of studies used one of 38 unique dietary indices (n=677; 31%).

Conclusions: The use of WWEIA, NHANES data in the scientific literature is prominent, and has grown over time. The widespread use of this national dietary surveillance data demonstrates its importance for continued nutrition research, surveillance, and policy.