Foods, fortificants, and supplements: Where do Americans get their nutrients?
Level 4 - case-series / case-control
Cross-sectional survey analysis (NHANES).
PubMed 21865568 · doi:10.3945/jn.111.142257
What was done
Using data from the National Health and Nutrition Examination Survey (NHANES 2003-2006) for 16,110 U.S. residents aged ≥2 years, researchers assessed the contribution of naturally occurring food sources, fortified and enriched foods, and dietary supplements to usual intakes of 19 micronutrients using the National Cancer Institute method. Total usual intakes were compared against Dietary Reference Intake standards (Estimated Average Requirement [EAR], Adequate Intake [AI], and Tolerable Upper Intake Level [UL]).
What was found
Total usual intake fell below the EAR for vitamin D (70%), vitamin E (60%), magnesium (45%), calcium (38%), vitamin A (34%), and vitamin C (25%). Fewer people fell below the EAR for vitamin B-6 (8%), folate (8%), zinc (8%), and <6% for thiamin, riboflavin, niacin, vitamin B-12, phosphorus, iron, copper, and selenium. Intakes exceeded the AI for only 3% of the population for potassium and 35% for vitamin K. Enrichment and fortification heavily contributed to intakes of vitamins A, C, and D, thiamin, iron, and folate, while supplements further decreased shortfalls. Total intake exceeded the UL for niacin in 10.3% and zinc in 8.4% of the population.
Why it matters
This study demonstrates that without food fortification and dietary supplements, a substantial portion of the U.S. population would fail to meet basic micronutrient recommendations from naturally occurring dietary sources alone.
Limits
Data rely on self-reported dietary recalls and supplement use within a cross-sectional survey, which are subject to recall bias and reporting errors. Biomarkers of nutritional status or clinical deficiency outcomes were not reported in the abstract.
Cited by
- supports Approximately 50% of the population does not consume sufficient dietary magnesium.