Amino Acid Intake and Conformance With the Dietary Reference Intakes in the United States: Analysis of the National Health and Nutrition Examination Survey, 2001–2018

The lack of complete amino acid composition data in food composition databases has made determining population-wide amino acid intake difficult. This cross-sectional study characterizes habitual intakes of each amino acid and adherence to dietary requirements for each essential amino acid (EAA) in the US population. Food and Nutrient Database for Dietary Studies ingredient codes with missing amino acid composition data were matched to similar ingredients with available data so that amino acid composition could be determined for 100% of foods reported in the dietary intake assessment component of NHANES. Amino acid intakes during NHANES 2001–2018 (n = 72,831; ≥2 y) were calculated as relative (mg·kg of ideal body weight−1·d−1) intakes. Data from NHANES 2011–2018 were used to determine the percentage of population consuming less than that recommended by the DRIs for each EAA by age, sex, and race/ethnicity. Relative intakes of EAAs and NEAAs were greatest in those 2–3 y and lowest in older individuals (≥71 y or ≥80 y). In females aged 2–18 y, relative intakes of EAAs were lowest in non-Hispanic White (NHW; histidine, lysine, threonine, methionine, and cysteine) and non-Hispanic Black (NHB; valine, isoleucine, leucine, phenylalanine, tryptophan, and tyrosine) populations and highest in the Asian population. In females aged ≥19 y, relative intakes were lowest in NHW (lysine and methionine only) and NHB populations and highest in the Asian population. In males aged 2–18 y, relative intakes of EAAs were lowest in the NHB population and highest in the Asian population. In males ≥19 y, relative intakes were lowest in NHB and NHW (lysine only) populations and highest in the Hispanic population. Less than 1% of individuals aged ≥19 y did not meet the Estimated Average Requirements for each EAA. EAA intakes in the US population exceed recommended minimum population requirements. Future studies can use the method described here to quantify amino acid intake and examine relationships with health and disease.