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| Tests have shown that levels of heavy metal in the body may not be reflected by the levels in the hair.<ref name="teresa">Teresa M, Vasconcelos SD, Tavares HM. Sci Total Environ. 1997 Oct 20;205(2-3):189-99.</ref> | Tests have shown that levels of heavy metal in the body may not be reflected by the levels in the hair.<ref name="teresa">Teresa M, Vasconcelos SD, Tavares HM. Sci Total Environ. 1997 Oct 20;205(2-3):189-99.</ref> | ||
| == Peer-reviewed Findings that Support a Rôle for Hair Analysis in Medicine == | == Peer-reviewed Findings that Support a Rôle for Hair Mineral Analysis in Medicine == | ||
| Despite this lack of consensus, there is evidence to suggest that hair analyses can be a useful tool in both medical research and in clinical diagnostics. For example, a 2003 study in the International Journal of Toxicology found that hair mercury levels in autistic infants do, indeed, significantly differ from those in healthy children. <ref name="Holmes">Holmes AS, et al. Reduced levels of mercury in first baby haircuts of autistic children. <i>Int J Toxicol</i>. 2003 Jul-Aug;22(4):277-85. </ref> As one of the co-authors of this paper was the chairman of the ] department at the ], it would appear that this is serious science. <ref name="haley ">Haley B. Interview accessed at www.youtube.com January 26, 2007</ref> | Despite this lack of consensus, there is evidence to suggest that hair analyses can be a useful tool in both medical research and in clinical diagnostics. For example, a 2003 study in the International Journal of Toxicology found that hair mercury levels in autistic infants do, indeed, significantly differ from those in healthy children. <ref name="Holmes">Holmes AS, et al. Reduced levels of mercury in first baby haircuts of autistic children. <i>Int J Toxicol</i>. 2003 Jul-Aug;22(4):277-85. </ref> As one of the co-authors of this paper was the chairman of the ] department at the ], it would appear that this is serious science. <ref name="haley ">Haley B. Interview accessed at www.youtube.com January 26, 2007</ref> | ||
Revision as of 20:23, 26 January 2007
Main article: Hair analysisHair 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.
To summarize the debate about the usefulness of hair analysis in medicine, it is important to note that it is not so much one debate as three debates: one about the techniques of determining hair minerals and metals, and hence the reliability, credibility and comparability of individual labs (i.e. how do labs generate their values? Are these techniques sound? And can values that different labs obtained using different techniques be meaningfully compared?); a second one about the interpretation of hair tests (i.e. what causes low mercury in a hair test?) and a third one, about the therapies that hair tests are purported to suggest (i.e. if polonium levels are two hundred times larger than uranium levels, should a physician do more than urge the patient to avoid sushi bars in the future?) These are complex questions for which science today does not always have clear unambiguous answers to offer.
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. 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.
Peer-reviewed Findings that Support a Rôle for Hair Mineral Analysis in Medicine
Despite this lack of consensus, there is evidence to suggest that hair analyses can be a useful tool in both medical research and in clinical diagnostics. For example, a 2003 study in the International Journal of Toxicology found that hair mercury levels in autistic infants do, indeed, significantly differ from those in healthy children. As one of the co-authors of this paper was the chairman of the chemistry department at the University of Kentucky, it would appear that this is serious science.
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.
- ^ Holmes AS, et al. Reduced levels of mercury in first baby haircuts of autistic children. Int J Toxicol. 2003 Jul-Aug;22(4):277-85.
- 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.
- Haley B. Dr. Boyd Haley on Mercury toxicity & Autism. Interview accessed at www.youtube.com January 26, 2007
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