Serum Zinc Concentrations in the US Population Are Related to Sex, Age, and Time of Blood Draw but Not Dietary or Supplemental Zinc

Serum zinc concentration is used to assess the zinc status of populations. Cutoffs for serum zinc were developed on the basis of data from the second NHANES (1976–1980). The objective of this study was to evaluate serum zinc concentrations in the US population and to determine factors affecting serum zinc with the use of NHANES 2011–2014. Serum zinc was determined in males and females aged ≥6 y with the use of NHANES 2011–2014 (n = 4347). Dietary zinc intake was determined, and factors affecting serum zinc were identified with the use of regression models adjusting for sex, age, fasting status, and time of blood draw. ORs were calculated to identify factors associated with the risk of being below the serum zinc cutoff, and the prevalence of low serum zinc in the US was calculated. P