Journal Title (Medline/Pubmed accepted abbreviation): J Nutr
Page numbers: 261-266
doi (if applicable): 10.3945/jn.110.133025
Summary of Background and Research Design
Background:The National Health and Nutrition Examination Survey (NHANES) has collected data on the use of dietary supplements in the United States since the early 1970s and has shown an increased use through the early 1990s.
Hypothesis/purpose of study: To update the estimate of dietary supplement use in all ages of the population between the years 2003 and 2006.
Subjects:The study included either self-reported or parental interview data on dietary supplement usage for 18,758 individuals ≥ 1 year of age; pregnant women were excluded.
Experimental design:Retrospective database analysis
Treatments and protocol:Individuals answered survey questions on dietary supplement usage over the past 30 days including vitamins, minerals, herbals, and other supplements. Type, frequency, duration, and amount were also collected for each supplement reported. Supplements were also evaluated by class: multi-vitamin, multi-vitamin with minerals, botanicals, and amino acid-containing. Data were stratified by age group, with differing limits for individual supplements.
Summary of research findings:
- Dietary supplement use was reported by 49% of the population (males, 44%; females, 53%) ≥ 1 year of age.
-Use increased with age; among adults, use was 54%.
– In general, teenagers (14 to 18 years) had the lowest dietary supplement usage (26%).
- The majority of individuals, evaluated for the number of daily supplements used, took 1 dietary supplement (n = 9,132).
– 10% of the individuals took > 5 dietary supplements daily.
- Supplement use was associated with weight, education, and ethnicity.
– Overweight individuals were less likely to use supplements.
– More highly educated individuals and non-Hispanic whites were more likely to use supplements.
- Among the 4 supplement classes, a multi-vitamin with minerals was used most commonly (33%).
– A multi-vitamin with minerals was used most commonly in individuals ≥ 51 years of age and in males 4 to 8 years of age.
- In general, vitamins (A, B6, B12, C, E, and K) were used most commonly in older individuals (age groups ≥ 51 or ≥ 71 years) and in children (age groups 4 to 8, ≤ 8, or 8 to 13 years).
- Mineral use ranged from 18% (iron) to 27% (magnesium) in the overall population.
-Iron supplements were used most commonly among children in the 4 to 8 years age group and among women in the 19 to 50 years age group.
- Botanical supplement use was reported in approximately 20% of adults as part of a supplement combination or a single product.
Interpretation of findings/Key practice applications:
The use of dietary supplements is high in the US population. The multi-vitamin with minerals was the most common supplement in this study, which is consistent with the findings of other studies. There is a clear pattern of increasing supplement use over time with age. Overall, the use of dietary supplements increased approximately 10% from the last analysis (1988 to 1994). Among adolescents, supplement use remained similar to the results of the last analysis, while children 4 to 8 years showed a decrease. The use of supplements containing calcium, vitamin A, or folic acid remained similar to the last analysis among children; however, the use of iron-containing supplements decreased 5% to 7% for children 1 to 13 years of age. However, there is no standard definition of a multi-vitamin with minerals; therefore, comparisons should be interpreted with caution. Dietary supplements need to be considered when assessing for nutrient inadequacy or excess because supplements may contain nutrients in amounts as high as or higher than the daily recommended intake and contribute substantially to total nutrient intake.