Nutrients in the US Diet: Naturally Occurring or Enriched/Fortified Food and Beverage Sources, Plus Dietary Supplements: NHANES 2009–2012

BACKGROUND: Nutrients are added to the diet through fortification/enrichment and dietary supplements (DSs). Meeting the US Dietary Reference Intakes (DRIs) varies by nutrient and population subsegments. OBJECTIVE: The aim of this study was to assess the relative role of naturally occurring, enriched/fortified, and DS sources of 15 micronutrients with reference to the DRIs. METHODS: We used the NHANES 2009-2012 (≥2 y old, n = 16,975) data, the ILSI North America Fortification database, and the National Cancer Institute usual intake method. RESULTS: Prevalence of nutrient intake from naturally occurring sources below the Estimated Average Requirement (EAR) varied from 5% for vitamin B-12 to 100% for vitamin D, with ≥40% of the population below the EAR for 8 of the 14 nutrients (ages ≥2 y). With enrichment/fortification, the percentage below the EAR decreased to the following for vitamins A (35%), C (34%), and B-6 (7%), folate (8%), thiamin (5%), riboflavin (3%), niacin (1%), and iron (2%). Nutrients from DSs further improved intakes related to the EAR for 12 nutrients (ages ≥2 y). For 9-18-y-olds, the percentages of nutrient intakes below the EAR were 14-50% higher than for 2-8-y-olds. The Tolerable Upper Intake Level (UL) was exceeded among children aged 2-8 y for folate (41.7%), niacin (10.1%), and zinc (39.9%), whereas among ages ≥2 y and 9-18 y no prevalence of intakes over the UL exceeded 10%. CONCLUSIONS: Fortification/enrichment constitutes a meaningful contribution to reducing the percentage of individuals with less than the EAR for their demographic. These data underscore the need to encourage better dietary patterns to improve the intake of nutrients at risk of low intake.