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Other common
name(s): glyconutritionals, Ambrotose, Glycentials, and
others
Scientific/medical
name(s): mannose, galactose, fucose, xylose, glucose,
sialic acid, N-acetylglucosamine, N-acetylgalactosamine
Description
Glyconutrients refers to a group of eight sugars, or
monosaccharides, that are used by cells in the body to make two
important types of molecules: glycoproteins (proteins with sugar
molecules attached) and glycolipids (lipids with sugar molecules
attached). These molecules are important in the communication that
occurs between cells. In recent years, various combinations of these
sugars have been sold as dietary supplements with a supposed wide range
of health benefits.
Overview
Glyconutrients can all be made by the human body. 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.
How is it promoted for use?
Glyconutrients are often promoted as being "essential sugars,"
in much the same terms as the essential amino acids—in other
words, as sugars that the body cannot do without. Proponents of
supplements containing glyconutrients claim that people are often
deficient in these sugars. While it is true that these sugars are
needed for signaling between cells, they do not have to be ingested in
supplement form. The human body can make them from nutrients normally
found in food.
Promoters claim that glyconutrient supplements have a wide
range of helpful effects, including improving memory and sleep,
lessening anxiety and depression, and lowering blood pressure and
cholesterol levels. They are also claimed to help retain muscle mass,
reduce body fat, aid in wound healing, and reduce symptoms from
autoimmune disorders such as allergies and arthritis.
Perhaps the biggest claim for these products is that they help
boost the immune system, which in turn is supposed to help the body
defend against a range of diseases, including cancer.
What does it involve?
The sugars sold as glyconutrients are found in many plant
sources, but mixtures of glyconutrients are more commonly sold as
dietary supplements in capsule or powder form. Each brand may have
different ingredients, so there is no standard dosage.
What is the history behind it?
Researchers began studying glycoproteins and glycolipids in
the middle of the twentieth century and, over time, have learned the
structure and functions of many of these molecules. Their importance in
signaling between cells has become clear in the last few decades,
although many of the details of their actions remain to be worked out.
Although proponents of glyconutrient supplements claim that people are
deficient in some of the sugars used to make glycoproteins, researchers
have found that the human body can make these substances on its own.
Glyconutrients as dietary supplements have only become popular in the
last decade or so, in large part because of aggressive promotion by
marketing companies.
What is the evidence?
There is a wealth of laboratory evidence that glycoproteins
are important in communication between cells and that this in turn may
affect body systems such as the immune system.
However, other than the rare exception of people with certain
inherited genetic diseases, available scientific evidence does not
suggest that people are deficient in the sugars considered
"glyconutrients." Available evidence does not support claims that such
deficiencies lead to disease.
There are no reliable, controlled studies in the medical
literature that show that taking glyconutrient supplements has any
effect on cancer or other disorders. The few individual case reports
mentioned by promoters of glyconutrient supplements have appeared
mainly in obscure medical journals or cannot be found in published
medical literature. More rigorous scientific studies are needed to
clarify any possible benefit from taking such supplements.
Are there any possible problems or
complications?
This product is sold as a
dietary supplement in the United States. Unlike companies that produce
drugs (which must provide the FDA with results of detailed testing
showing their product is safe and effective before the drug is approved
for sale), the companies that make supplements do not have to show
evidence of safety or health benefits to the FDA before selling their
products. Supplement products without any reliable scientific evidence
of health benefits may still be sold as long as the companies selling
them do not claim the supplements can prevent, treat, or cure any
specific disease. Some such products may not contain the amount of the
herb or substance that is written on the label, and some may include
other substances (contaminants). Though the FDA has written new rules
to improve the quality of manufacturing processes for dietary
supplements and the accurate listing of supplement ingredients, these
rules do not take full effect until 2010. And, the new rules do not
address the safety of supplement ingredients or their effects on health
when proper manufacturing techniques are used.
Most such
supplements have not been tested to find out if they interact with
medicines, foods, or other herbs and supplements. Even though some
reports of interactions and harmful effects may be published, full
studies of interactions and effects are not often available. Because of
these limitations, any information on ill effects and interactions
below should be considered incomplete.
It is unclear whether rigorous safety testing has been done on
dietary supplements containing glyconutrients. The ingredients come
mainly from plant sources, and there appear to be few side effects
other than possible allergic reactions to the plants used in the
supplements. Relying on this type of treatment alone and avoiding or
delaying conventional medical care for cancer may have serious health
consequences.
Additional Resources
More information from your American Cancer
Society
The following information on complementary and alternative
therapies may also be helpful to you. These materials may be found on
our Web site (www.cancer.org)
or ordered from our toll-free number (1-800-ACS-2345).
References
Barrett S. Mannatech claims criticized. Consumer Health Digest
#06-44. October 31, 2006. National Council Against Health Fraud Web
site. http://www.ncahf.org/digest06/06-44.html. Accessed June 5, 2008.
Glyconutrients. Memorial Sloan-Kettering Cancer Center Web
site. http://www.mskcc.org/mskcc/html/70468.cfm. Updated December 18,
2007. Accessed June 5, 2008.
Greenberg H. Texas attorney general probing Mannatech
commentary: focus on health claims for nutritional supplements. October
26, 2006. Marketwatch Web site.
http://www.marketwatch.com/news/story/story.aspx?siteid=mktw&guid=%7B50E126AD-F88B-4070-BA5E-635DDD72B298%7D.
Accessed June 5, 2008.
Note: This information may not cover
all possible claims,
uses, actions, precautions, side effects or interactions. It is not
intended as medical advice, and should not be relied upon as a
substitute for consultation with your doctor, who is familiar with your
medical situation.
Last Medical Review: 11/01/2008
Last Revised: 11/01/2008
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