A California company is marketing the latest in dietary supplements, an extract from algae they claim will boost the number of circulating stem cells, easing disease and discomfort. Consumers have already spent millions on the "stem cell enhancer," but some stem cell researchers remain unconvinced the product even works -- and warn that the "enhancer" may trigger other problems, including cancer.
"I would look at this with great, great, great skepticism," said William Frishman
at the New York Medical College in Valhalla.
"I strongly advise anybody not to take this drug" until more studies are done, said Thomas Eschenhagen
, a professor at the University Medical Center Hamburg-Eppendorf. Eschenhagen told The Scientist
the effect of the product does not appear drastic, based on information from the company. But whether it's safe, "we simply don't know."
According to STEMTech HealthSciences
, the product, StemEnhance, made from the blue-green algae Aphanizomenon flos-aquae
, promises to "support your stem cells in maintaining proper organ and tissue functioning in your body." The product is marketed online and at least one distributor advertises with leaflets door-to-door, asking "What have your STEM CELLS done for you lately?"
Online testimonials of StemEnhance claim a range of benefits, including reducing hot flashes and heartburn, easing withdrawal from methamphetamine addiction, and curing chronic back pain. In response to a The Scientist Blog
about the product, one customer and distributor wrote the product cured knee and back pain, and discomfort from kidney cysts. "Since starting this product-I no longer have kidney or back pain, I personally can go hours without urinating which before I swear was at least once an hour and my knees don't hurt when I get up off the toilet."
Others are less enthusiastic. The "skeptical guide to multilevel marketing" Web site MLM Watch
calls StemTech's claims "dubious." On the Web site Wellness Clubs of America
, dedicated to promoting healthy lifestyle, founder Dale Peterson questions the safety of ingesting potentially toxic algae, stating "People love magic pills, gimmicks & slick web sites, even when they may be hazardous to their health. I have to give Stem Enhance's creators credit -- not everyone could turn a potentially deadly pond scum into the cure-for-all-diseases."
Anecdotally, there has been overwhelming evidence the product -- sold for approximately $1 per pill -- does wonders, Christian Drapeau, StemTech's Chief Science Officer, told The Scientist
. In some cases, diabetics have ceased taking insulin, wheelchair-bound people with multiple sclerosis have walked, and Alzheimer's and Parkinson's patients experienced improved cognitive function, he said. "It's pretty clear it is a natural process of healing."
Drapeau estimated the company has sold 425,000 bottles -- approximately $60 each -- since November 2005, and is now selling roughly 50,000 bottles per month.
The extract elevates circulating stem cells by the actions of two uncharacterized compounds, one that acts to stimulate release of cells from the bone marrow, and another that facilitates migration of the cells to tissues all over the body, said Drapeau.
Drapeau said he has tested one of the compounds in humans, and it acts as a blocker of L-selectin
, a cell adhesion molecule. Drapeau said the compounds are as yet unnamed. An article due for publication in Cardiovascular Revascularization Medicine
suggests an extract from A. flos-aquae
mobilizes CD34+ stem cells from the bone marrow, he added. The managing editor of the journal confirmed the paper is expected to publish this summer.
This is a somewhat plausible mechanism, according to Wojtek Wojakowski
at the Silesian School of Medicine in Katowice, Poland. An extract that acts as an L-selectin blocker could elevate circulating stem cells, which may "help with [cells] leaving
the bone marrow," Wojakowski told The Scientist
. "But this approach was not tested in clinical studies."
The company Web site presents results from 15 volunteers, showing that cells in the blood labeled with CD34 antibody increased by about 25% within an hour after taking StemEnhance.
But many stem cell researchers remain unconvinced. "At this point there's no clear-cut evidence that an increase of these stem cells is something good," Eschenhagen said. Scientists debate
the role of circulating progenitor cells in healing injury, particularly regarding cardiovascular damage
, he said, and have reached no consensus as to whether supplementing
progenitor numbers improves tissue repair
"Basically I think that it's true that higher levels of endothelial progenitor cells have been associated with better long-term [health] outcomes
," said Kreton Mavromatis
at Emory University. But there is no causative study showing those cells are responsible for improved health, Mavromatis told The Scientist
And if the product does what it says, it may not be safe, according to Frishman. One of the risks of taking a stem cell enhancer is that it could activate dormant cancer cells, he told The Scientist
. There are other stem cell enhancing drugs that target particular cell types, such as granulocyte colony-stimulating factor, which elevates white blood cells after chemotherapy. "Here [with StemEnhance] you're giving a general stem cell booster," Frishman said. "Some people might have occult malignancies and all of a sudden you're giving them a stem cell booster."
Drapeau said he has not seen any evidence the product causes harm, and is hesitant to produce too much data saying it works, out of fear the US Food and Drug Administration will revoke its status as a dietary supplement -- where it's available to everyone sick and well -- and consider it a drug that requires a prescription. "We have not yet documented in a rigorous manner the health benefits [of StemEnhance] essentially because they are so obvious, and I am concerned if we get data showing the product is effective...we will be in a difficult position with the FDA," Drapeau said.
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