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Hair analysis is the chemical analysis of a hair sample. It is used in some branches of alternative medicine as a method of investigation to assist diagnosis. This use is controversial.
Background
The hair is analyzed, looking at the levels of minerals and metals in the hair sample. Using the results, advocates claim that they can diagnose mineral deficiencies, heavy metal poisoning and even conditions like autism.
Unreliable and inconsistent results
In a 1985 investigation of 13 commercial laboratories published in the Journal of the American Medical Association noted inconsistencies and questionable content in their reports and recommendations:
- "Hair samples from two healthy teenagers were sent under assumed names to 13 commercial laboratories performing multimineral hair analysis. The reported levels of most minerals varied considerably between identical samples sent to the same laboratory and from laboratory to laboratory. The laboratories also disagreed about what was "normal" or "usual" for many of the minerals. Most reports contained computerized interpretations that were voluminous, bizarre, and potentially frightening to patients. Six laboratories recommended food supplements, but the types and amounts varied widely from report to report and from laboratory to laboratory. Literature from most of the laboratories suggested that their reports were useful in managing a wide variety of diseases and supposed nutrient imbalances. However, commercial use of hair analysis in this manner is unscientific, economically wasteful, and probably illegal."
In 2001 a follow up investigation was conducted to see if things had improved since the 1985 investigation
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.
Publication Types: Validation Studies
PMID: 11150111
When the same samples are sent to different laboratories offering the service, results differ from laboratory to laboratory. The authors concluded:
- "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."
George Tamari, the owner of a medical and diagnostic laboratory, commented on this investigation and explained that this may be the result of lack of standardization in the analysis protocols, rather than a flaw in the concept. In addition, he stated that "any analytical laboratory, whether analyzing hair, blood or urine, has no valid rationale for recommending a supplementation program based solely on the specific analysis. Only a qualified health practitioner, who has all the necessary and appropriate information about the patient, is in the position to make proper interpretation and appropriate recommendations." Finally there is the problem that hair will be up to two weeks old meaning that the data obtained may not reflect the current state of the person the hair was taken from.
Its viability for use in forensics has also been questioned.
Tests have shown that levels of heavy metal in the body may not be reflected by the levels in the hair.
References
- Lathe, Richard, and Michael Le Page. "Toxic metal clue to autism: a study has revealed startling differences in mercury levels in the hair of autistic and normal children. (This Week)." New Scientist 178.2400 (June 21, 2003): 4(2).
- Barrett S. Commercial hair analysis: Science or scam? JAMA 254:1041-1045, 1985.
- ^ Seidel S, Kreutzer R, Smith D, McNeel S, Gilliss D. Assessment of commercial laboratories performing hair mineral analysis. Journal of the American Medical Association, 2001 Jan 3;285(1):67-72.
- George Tamari. Unreliability of hair analysis. Letter to the editor: Townsend Letter for Doctors and Patients, May, 2004
- Wennig, R. "Potential problems with the interpretation of hair analysis results.(Selected Papers from the 2d International Meeting of the Society of Hair Testing)."Forensic Science International 107.1-3 (Jan 10, 2000): 5-12.
- Teresa M, Vasconcelos SD, Tavares HM. Trace element concentrations in blood and hair of young apprentices of a technical-professional school. Sci Total Environ. 1997 Oct 20;205(2-3):189-99.
External links
- AETNA Clinical Policy Bulletin: Hair Analysis
- Commercial Hair Analysis: A Cardinal Sign of Quackery
- Dubious Mercury Testing
- Study Questions Reliability of Hair Tests
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