Wikipedia
Wikipedia has a comprehensive entry on Glyconutrients. While the entry itself doesn’t talk about Mannatech (MT, but provides a link in the references), the Talk Page has quite a bit of discussion about MT going on, little in favor of MT:
“All technical types (people) rejected MT’s “glycoscience” schpiel – 8 essential dietary monosugars specifically“
“MT have demurred for years on executing simple tests that would (dis)prove its claims. Not exactly reassuring“
“Basically MT research seems to concentrate on production of small clinical tests of low confidence and zero scientific use – very convenient for sales talks. Who knows what McAnalley’s real results were, but not publishing them undermines the claims even further if he (or MannaTech) refuses to publish them or sponsor tests in a small but critical claims area. Also Dr McAnalley’s “unpublished research” claims simply are not verifiable“
Lawsuit against Mannatech
Turns out that Mannatech is a publicly listed company that’s traded on NASDAQ as MTEX. The Class Action Law Suit has been filed by investors against the management, specifically Samuel L. Caster, Terry L. Persinger, and
Stephen D. Fenstermacher. The lawsuit cites an article in Barron’s, an investor magazine with a prime reputation that is owned by the Wall Street Journal.
“The article questioned the legitimacy of the Company‘s business, and noted that despite the Company’s surface flash, eye-popping financials and grand plans, Mannatech‘s allure steadily dims the more intensely one scrutinizes its provenance and how it makes its living. Specifically, the article detailed Caster’s history and questioned the methods of the Company’s sales associates.“
PubMed
PubMed, the online service of the National Library of Medizine, has five hits on Manatech. Some background: PubMed is a database of publications that cover research that was funded in full or in part by the US government. These publications are usually peer reviewed and credible.
I had only abstracts available. Not mutch information could be extracted from those. Out of the 5 articles, 4 were published by Mannatech. Only the 2 oldest papers (1998) deal with specific deseases (attentional-deficit hyperactivity disorder and fibromyalgia and chronic fatigue syndrome), neither with conclusive results.
2 articles deal with determining the quality of dietary products related to glyconutrients, published in 2005.
The last article (published in 2002 by Baylor College of Medicine, Houston) deals with steroid treatment. It discusses the impact of supplements (including those from MT) on the treatment.
Nothing conclusive here, but I would have expected more publications, considering how revolutionary MT products supposedly are. Specifically, I am very surprised that there was no publication on the “8 essential dietary monosugars”.
HIV and Mannatech
There were statements about the impact of MT’s products on HIV. The information seems to come from a 2005 publication in an Ugandan Newspaper, New Vision. There are no clamis that HIV can be cured, it is simply stated that the use of Glyconutriens fights the symptoms of AIDS. No studies have been cited, but statements from doctors instead:
“Dr Akenga used these glyconutrients three years ago on HIV/AIDS patients. (…) “The patients had many clinical manifestations of the HIV/AIDS and were bedridden,” he says. Akenga says within two weeks, all the patients who received the glyconutrients had recovered. “They were walking. (…)” “
Mannatech Website
So far, little support for Mannatech. Next I visited their web site (www.mannatech.com), but there was absolutely no scientific information to be found there. Even more surprising, the only success stories I could find there were business success stories, no health success stories!
But Mannatech also has a scientific marketing website, glycoscience.com. This site has a list of 60 publications. Here are some interesting findings:
The latest paper listed there is from 2004, in the section “Human Obersational: Retrospective and prospective studies”: Effect of nutritional supplementation in peripheral neuropathy: a pilot study. This pilot didn’t show any objective inprovement due to the administration of glyconutrients:
“Nine of 12 patients (75%) reported subjective improvement in (…) their quality of life (…). However, objective nerve conduction velocity tests were mixed with no overall significant trend at 6 months. Conclusion: This study suggests that the addition of glyconutrients, phytonutrients and a plant sterol complex to the diet of patients suffering from peripheral neuropathy may improve their symptoms and quality of life but has no significant impact on objective nerve conduction velocity tests.“
The paper An Open-Label Pilot Study of the Antioxidant Effect in Healthy People of Ambrotose AO isn’t specific to glyconutrients but antioxidants, but uses a Manatech product for the study. The results are positive, but show nothing that couldn’t be achieved by eating the suggested daily serving of fruit and vegetables:
“While it is still recommended that individuals consume fruits and vegetables according to published guidelines, the reality is that the vast majority will not. These preliminary data suggest that a nutritional supplement containing optimal antioxidant ingredients (…) increases antioxidant protection in healthy individuals (…).“
Society for Glycobiology
The Society for Glycobiology seems to be a serious association that, at least now, clearly disassociates itself from manufacturers of “so-called glyconutrients, glyconutritionals, or other similarly named products“. If these products were as revolutionary as MT associates claim, I would expect a different response here.
Conclusion
At this point, there is little evidence (except annecdotal evidence by associates) that Mannatech products are superior to high-quality multivitamins. Even MT’s own studies don’t show more. On top of that, MT’s marketing techinques don’t help to strengthen confidence in this company. And the pending lawsuit doesn’t help either (even though that only affects management, not the products. But then again, fish from the head down).
In short, money on a basket of fresh fruit and a gym membership may be a better investment into one’s health.