Author Affiliations: Impact Assessment Inc, for the California Department of Health Services, Environmental Health Investigations Branch (Dr Seidel), and California Department of Health Services, Environmental Health Investigations Branch (Drs Kreutzer, Smith, McNeel, and Gilliss), Oakland.
Context Hair mineral analysis is being used by health care practitioners and
promoted by laboratories as a clinical assessment tool and to identify toxic
exposures, despite a 1985 study that found poor reliability for this test.
Objective To assess whether the reliability of data from commercial laboratories
advertising multimineral hair analyses for nutritional or toxicity assessment
has improved since the 1985 study.
Design, Setting, and Participants A split hair sample taken from near the scalp of a single healthy volunteer
was submitted for analysis to 6 commercial US laboratories, which analyze
90% of samples submitted for mineral analysis in the United States.
Main Outcome Measures Agreement of test results for each analyte, laboratory reference ranges,
laboratory characteristics, and interpretation of health implications.
Results Laboratory differences in highest and lowest reported mineral concentrations
for the split sample exceeded 10-fold for 12 minerals, and statistically significant
(P<.05) extreme values were reported for 14 of
the 31 minerals that were analyzed by 3 or more laboratories. Variations also
were found in laboratory sample preparation methods and calibration standards.
Laboratory designations of normal reference ranges varied greatly, resulting
in conflicting classifications (high, normal, or low) of nearly all analyzed
minerals. Laboratories also provided conflicting dietary and nutritional supplement
recommendations based on their results.
Conclusions Hair mineral analysis from these laboratories was unreliable, and we
recommend that health care practitioners refrain from using such analyses
to assess individual nutritional status or suspected environmental exposures.
Problems with the regulation and certification of these laboratories also
should be addressed.
Seidel S, Kreutzer R, Smith D, McNeel S, Gilliss D. Assessment of Commercial Laboratories Performing Hair Mineral Analysis. JAMA. 2001;285(1):67–72. doi:10.1001/jama.285.1.67