Talk:Glyconutrient/revision-2007

A glyconutrient is an individual carbohydrate nutrient. More recently, the commercially inspired terms Glyconutritionals and glyconutrients, have been used to refer to mixtures of dietary supplements that contain monosaccharides functionality or polysaccharides, such as exudate tree gums and high molecular weight aloe vera extracts, shii-ta-ke mushroom extracts, containing fermentable dietary fiber and plant extracts, as well as sugars or starch. Polysaccharides are large sugar polymers made up of monosaccharide monomers such as glucose, galactose, fucose, fructose, mannose, xylose and arabinose.

Polysaccharides are not digested and absorbed by the human digestive tract but rather are utilized by intestinal bacteria to create several kinds of short chain fatty acids, important nutrients, bacterial biomass, and other gastrointestinal benefits.{CN}} Some very long chain polysaccharides may have gut immunity stimulation properties (Lentinan, KS2, AC2P, etc).

The use and marketing of glyconutrients has been popularized worldwide by the Mannatech corporation.

Characteristics
The polysaccharide components have a significant degree of polymerization, often over 100, with the highest molecular weight polymers well over 1,000,000 daltons. Some glyconutrient formulas may contain an individual sugar (e.g. glucosamine) or starch either as a functional food or filler. Other minor content such as minerals, protein and peptides may be present from the natural sources. The polysaccharides in glyconutrient formulas typically have higher molecular weight components, monosaccharide structural units less common in prebiotics, and, possibly, additional mechanisms of action over typical prebiotics containing oligosaccharides and shorter polysaccharides.

Use as alternative therapy dietary supplement
A number of companies sell formulas labeled as glyconutrients. Also individuals attempt to empirically optimize formulas for perceived individual performance and to reduce costs. Components of various mixtures have included high molecular weight extracts from aloe vera, high molecular weight arabinogalactan fraction of Larch extract, gum arabic (gum acacia), ghatti gum, gum tragacanth, oat fiber, fenugreek seed, kelp, Shiitake mushroom, Shii-ta-ke concentrated extract, Reishi mushroom, cordyceps, psyllium husk, bovine cartilage powder, xylitol, Red Roselle, and glucosamine. Many of these components have long been used in food processing and health remedies.

Nutritional and medical sciences have long noted soluble fiber, including polysaccharides, as largely undigested in the small intestine. The soluble fibers are then fermented in the colon into highly beneficial short chain fatty acids, n-butyrate being especially beneficial. Anti-inflammatory benefits are have been long associated with various ingredients, including gum acacia, Red Roselle extracts and glucosamine.

There are claims that current research supports effects benefits and mechanisms such as increased beneficial bacteria (e.g. bifidus, lactobacillus) - a prebiotic effect, a decrease in opportunistic pathogens, immune activation and stimulation, increased efficiency of digestion and absorption of nutrients, decreased circulating free fatty acids that cause cellular insulin resistance, decreased luminal ammonia concentration. For example, various clinical studies with arabinogalactans (AG) extracted from Larch examine prebiotic effects, immune stimulation and immune-enhancing effects, increases in total gut anaerobes, including beneficial gastrointestinal bacteria and reduced ammonia levels.

Amounts advertised as minimum vendor recommendations, apparently for healthy customers, are sometimes substantially lower than actual daily usage amounts reported by other customers as necessary to achieve satisfaction, often by a factor of 8 to 25. Amounts consumed typically depend upon individual perception of requirements for improvement, product cost, financial constraints, formulation and physiological limitations on fiber load. Self mixers report 70%-85% savings for high cost commercial formulations. In the US, during 2005, retail costs of typical "glyconutrient" formulations ranged from about $14, self mixed, to over $500 per pound ($30 - $1200+/kg) depending on source(s), quantity, and components.

Prebiotics, with a lower degree of polymerization, available under $8/lb for some mail order inulin sources, are used both as complementary and as alternative materials to glyconutrient formulas.

Relation to the science of glycobiology
For some sources of these formulas, sensationalism, misattributed scientific references and controversial marketing methods abound. Substantial supplementation with any dietary formula is generally recommended as a part of a comprehensive nutritional, medical or health plan, not a replacement for one. The Society for Glycobiology, "a nonprofit scholarly society devoted to the pursuit of knowledge of glycan structures and functions" has published a disclaimer on their website addressing "glyconutrients".

Some promoters of glyconutritional formulas espouse a popularized view that some of the polysaccharide components are being materially hydrolyzed and absorbed as monosaccharides for beneficial use in human cells. Based on this long unsubstantiated claim of significant digestion as monosaccharides and the popularized notion of "8 essential sugars (monosaccharides)", these promoters further claim physiological connections, broadly not accepted, to the established science of glycobiology as well as cellular phenomena such as glycosylation and formation of glycoproteins.

These popularized notions of digesting "8 essential sugars" from highly polymerized, complex carbohydrates have no support in science and medicine and have no significantly documented basis. There is no reliable evidence that people are generally deficient in glyconutrients, except for certain rare genetic diseases. There are enzymatic systems in place to convert nearly any sugar into any other sugar because they are fundamentally needed by the body. Furthermore, there are no reliable, controlled studies to show that glyconutrients provide any improvement against cancer.

Traditional and prior uses
Some "glyconutrients" extracted from vegetal or mushrooms fibers have been associated with health remedies, various forms of medicine, special foodstuffs, and food additives for centuries and even millennia, across many cultures, up to the present day.

Bibiliography

 * 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.