Herbal supplement use and blood lead levels of United States adults.
BACKGROUND
Some herbal supplements may contain lead.


OBJECTIVE
To examine whether use of specific herbal dietary supplements during the last 30 days is associated with blood lead levels in US men and women.


METHODS
Cross-sectional analysis.


METHODS
NHANES participants from 1999-2004, a representative sample of the civilian non-institutionalized US population.


METHODS
Lead was measured in blood. Associations between lead and self-reported supplement use were estimated using multivariable regression weighted to account for NHANES sampling. Herbal supplements investigated were those previously reported to contain high heavy metal content: Ayurvedic or traditional Chinese medicine herbs, echinacea, ginkgo, ginseng, St. John's wort, and "other" herbs (specifically, kava, valerian, black cohosh, bee pollen, and nettle).


RESULTS
Among 6,712 women > or =20 years, those using herbal supplements had lead levels that were 10% higher than non-users (95% CI 3%-17%, p = 0.005). Women using Ayurvedic or traditional Chinese medicine herbs, St. John's wort, and "other" herbs had lead levels 24% (95% CI 5%-45%, p = 0.01), 23% (95% CI 4%-46%), p = 0.02), and 21% (95% CI 2%-44%, p = 0.03) higher, respectively, than non-users. No significant associations were observed between herb use and lead levels among men (n = 6,095). Among reproductive-aged women (16-45 years), herbal supplement users had lead levels 20% higher than non-users (95% CI 5%-34%, p = 0.008). In contrast, garlic and other dietary supplements were not associated with higher lead levels.


CONCLUSIONS
Use of specific herbal supplements is associated with higher blood lead levels among women. Our data suggest testing guidelines for herbal supplements and regulations limiting lead in supplements are needed.
Buettner
Catherine
C
Division of General Medicine and Primary Care, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, USA. cbuettne@bidmc.harvard.edu
Mukamal
Kenneth J
KJ
Gardiner
Paula
P
Davis
Roger B
RB
Phillips
Russell S
RS
Mittleman
Murray A
MA
D000328:Adult; D003430:Cross-Sectional Studies; D019587:Dietary Supplements / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007854:Lead / Q000097:blood*; D007855:Lead Poisoning / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008517:Phytotherapy / Q000009:adverse effects; D028321:Plant Preparations / Q000009:adverse effects* / Q000097:blood*; D014481:United States / Q000453:epidemiology; D055815:Young Adult
D028321:Plant Preparations; D007854:Lead