Glyconutrient

Glyconutrient is a term used by the multi-level marketing company Mannatech, and other supplement vendors, to describe dietary supplements that contain a blend of simple sugars (monosaccharides) which are found in glycoproteins.

As Mannatech uses the term in labeling many of its products, "glyconutrient" refers to mixtures of polysaccharides, such as exudate tree gums and high molecular weight aloe vera extracts containing fermentable dietary fiber and plant extracts, as well as simple sugars or starch. Fact|date=October 2007 The company's SEC filing more precisely identifies the contents of Ambrotose, its lead product, as "a glyconutritional dietary supplement ingredient consisting of a blend of monosaccharides, or sugar molecules." [Mannatech, Incorporated, [http://www.sec.gov/Archives/edgar/data/1056358/000119312507056895/d10k.htm Form 10K SEC Public Filing for FY 2006] Retrieved on April 14, 2007.] In the marketing literature, these sugars are said to be a blend and the precursors of the following eight simple sugars: Xylose, Fucose, Galactose, Glucose, Mannose, "N"-acetylgalactosamine, N-acetylglucosamine, and N-acetylneuraminic acid [https://www.mannatech.com/Shopping/ScienceOfWellness.aspx Mannatech.com "The Science of Wellness"] by Mannatech Retrieved May 6, 2007.] .

The glyconutrients are identified in the textbook Harper's Biochemistry as providing the composition for glycoprotein structures which are the basis for cell-to-cell communication. [Harper's Illustrated Biochemistry, 27th Edition, Chapter 46, "Glycoproteins", pp 523-544.]

tudies

* In an "in vitro" study whose lead author was a paid consultant ["Mannatech suit accuses former consultant of fraud" http://nl.newsbank.com/nl-search/we/Archives?p_product=DM&p_theme=dm&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0ED3DBBC0A289DDA&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM] , glyconutrients were added to samples of peripheral mononuclear cells taken from patients with chronic fatigue syndrome (CFS). When these cells were subsequently exposed to cells infected with herpes, they demonstrated increased activity compared with placebo. Other abnormal immune parameters were also improved in the CFS cells. cite journal |author=See DM, Cimoch P, Chou S, Chang J, Tilles J |title=The in vitro immunomodulatory effects of glyconutrients on peripheral blood mononuclear cells of patients with chronic fatigue syndrome |journal=Integrative physiological and behavioral science : the official journal of the Pavlovian Society |volume=33 |issue=3 |pages=280–7 |year=1998 |pmid=9829439 |doi= |issn= |accessdate= |quote="Dr. See was a paid consultant."]

Health claims

Many glyconutrient supporters claim that these sugars have become deficient in the modern diet; they maintain that supplementation can provide health benefits across a wide array of disorders. The American Cancer Society states "Available scientific evidence does not support claims that people are deficient in these sugars, or that dietary supplements containing them can prevent, treat, or cure cancer or any other disease." [http://www.cancer.org/docroot/ETO/content/ETO_5_3x_Glyconutrients.asp?sitearea=ETO American Cancer Society question page] for glyconutrients] There are rare genetic disorders, such as leukocyte adhesion deficiency, in which the body cannot transport [http://www.nature.com/ng/journal/v28/n1/full/ng0501_69.html The gene defective in leukocyte adhesion deficiency II encodes a putative GDP-fucose transporter. "Nature Genetics", 2001] Retrieved June 10, 2007.] a "specific" sugar due to congenitally deficient enzymes. There are no reliable, controlled studies to show that glyconutrients provide any improvement against any medical disorder. [http://www.wellnessletter.com/html/ds/dsGlyconutrients.php Wellness Guide to Dietary Supplements] by the UC Berkeley School of Public Health, January 2006. Retrieved March 12, 2007.]

The claims for the value of glyconutrients have not been substantiated; a lawsuit was filed against Mannatech in September 2005 for violations of the Exchange Act related to material misrepresentations made by the company concerning its products' efficacy and uses. [http://www.findarticles.com/p/articles/mi_m0EIN/is_2005_Sept_12/ai_n15383042 Milberg Weiss Announces the Filing of a Class Action Lawsuit Against Mannatech, Inc. and Certain Individual Defendants on Behalf Of Investors] . Business Wire. September 12, 2005. Retrieved March 12, 2007.]

References

Further reading

* Martin Peterson, Arnold Johnson (1978) Encyclopedia of Food Science, Avi Publishing Co., Westport CT ISBN 0-87055-227-9
* Martin A. Rambal C. Berger V. Parlor S. Louisot P Availability of specific sugars for glycoconjugate biosynthesis. A need for further investigation in man. Biochemia 1988 pg.75-86
* Whelan W.J. Website Horrors - Essential What? IUBMB Life, 57, (10): 709, October 2005.
* Robert K. Murray, Daryl K. Granner, Victor W. Rodwell (2006) Harper's Illustrated Biochemistry, 27th Edition, Chapter 46, "Glycoproteins", pp 523-544, ISBN 0-07-147885-3.
* Maureen E. Taylor, Kurt Drickamer (2003) Introduction to Glycobiology, Oxford University Press, ISBN 0-19-925868-6

External links

* [http://www.highbeam.com/doc/1G1-151346646.html Nobel Prize winners say sites falsely cite research]
* [http://www.oag.state.tx.us/oagnews/release.php?id=2086 Texas Attorney General Charges Mannatech With Unlawful, Misleading Sales Practices]