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EDTA Chelation Therapy
Elizabeth Brown
What is chelation?
The word “chelation” comes from the
Greek for “claw.” Chelation is a process
by which metal ions in the body are bound to a chelating agent and excreted
from the body.
What is EDTA?
EDTA, ethylene diamine tetraacetic acid,
is a type of chelating agent. In
chelation therapy, it can be delivered orally or intravenously, and different
forms can be used for different purposes: disodium EDTA, magnesium disodium
EDTA, or calcium disodium EDTA.
What is EDTA chelation therapy?
Chelation therapy is often a series of
20-30 or more IV infusions of EDTA and vitamin/mineral supplements in a
doctor’s office spread out over the course of weeks and months. EDTA can also be taken orally, although it is
not absorbed as well and there is a debate among chelation practitioners over
its efficacy. The EDTA infusions are to
be placed in the context of healthy lifestyle changes such as diet, exercise,
not smoking, etc.
What is the purpose of this therapy?
ETDA chelation has been a standard
medical treatment for lead poisoning for decades, but its proponents claim that
it benefits a variety of other conditions.
Perhaps its most common application is in cardiovascular disease;
advocates claim that chelation reverses the hardening and occlusion of the
arteries, improving circulation to all parts of the body and avoiding expensive
coronary artery bypass grafting and angioplasty. Other conditions it purportedly benefits
include cardiac arrhythmia, diabetes, gangrene from peripheral arterial
disease, hypertension, Alzheimer’s, arthritis, senility, cancer, stroke,
scleroderma, cataracts, and more.
What evidence is there to support these
claims?
The website of the Mount Ranier Clinic
in
http://www.drcranton.com/chelation/research.htm
http://www.drcranton.com/chelation/allgood.htm
for Dr. Cranton’s discussion of some of these studies.
§
Blood flow to peripheral arteries (as objectively
measured by the Doppler ankle/brachial blood pressure ratio) improved by 22% in
77 elderly patients treated with EDTA chelation therapy.
§
A retrospective study of 470 subjects with
arteriosclerosis showed improvements of 80-90% with chelation therapy, and 82
out of the 92 patients who were to have surgery no longer needed it.
§
Four patients with gangrene from severe occlusive peripheral arterial
disease were to undergo amputations.
After EDTA chelation (and other treatments in some cases), all four
patients were healed and able to walk without pain (with only one subject
losing the tips of several toes).
§
EDTA chelation improved blood flow to the brain (as
measured by radioactive technique) and associated symptoms in 15 subjects.
§
A meta-analysis of 19 studies including 22,765 subjects
with cardiovascular disease showed that 87% of subjects benefited from
chelation therapy.
§
A study of 59 Swiss subjects treated with chelation
therapy and followed for 18 years showed a 90% reduction in cancer mortality
over untreated residents of the same neighborhood.
§
EDTA was shown to “enhance overall well-being and quality
of life” as measured by the Cornell Medical Index Health questionnaire and
broken down by body system. There was an
average of 20% improvement in the subjects.
§
A case study reported on the reversal of macular
degeneration in a 59-year-old woman treated with EDTA chelation therapy.
Many sites, including Dr. Cranton’s,
also have links to patient testimonials.
Here are some examples from the website selling Formula #1 Oral Chelation Therapy:
http://www.herbals-unlimited.com/formula_one.htm
§
“Ed and I are both taking 2
teaspoons a day of Formula #1 Oral Chelation - along with the heart pack that
has 2 Formula One Gel Caps in it! In the first two weeks my leg cramps were
gone!!! They used to be so bad that they would wake me up at night...I am so
glad they are gone. Ed's arm is no longer tingling when he wakes up in the
mornings. I did not know he had this problem till he told me it was gone since taking
the Formula One Oral Chelation. We look forward to the long term benefits of
this product. Ed and Trish Koch
§
“For about a year I was treated
for symptoms of heart attack and stroke. I started taking Formula #1 and got
results with in two days. I am 68 years old and returned to work full time in
construction. I can now work long hours with out any pain. I have reduced my
blood pressure medication and feel great with lots of energy. I owe it all to
Formula One Oral Chelation! Raymond S., USA EE 12/03”
How does EDTA do
all this?
According to
Dr. Cranton, “We really do not know how EDTA chelation therapy benefits
symptoms of atherosclerosis and arterial blockage. We do know a number of
different actions of EDTA within the body, but we do not know which actions are
most beneficial. It is quite possible that an unknown and still unsuspected
activity is primarily responsible for the observed improvement in blood flow
and symptoms.” http://www.drcranton.com/chelation/EDTA_Mysteries.htm
Many theories
have been put forward for consideration.
One of the more common explanations is that EDTA binds to the calcium in
arterial plaques and removes it, thus breaking up the plaque.
Some people
express concern over the binding of calcium, thinking that this process must
also strip away calcium from the bones and teeth. Proponents of the theory explain that the
calcium is only removed from inappropriate locations such as the arteries. Garry Gordon, M.D., D.O., adds that the
binding of calcium is actually good for the bones. Reduced serum calcium levels stimulate the
parathyroid gland to secrete parathormone,
which not only causes the restoration of appropriate calcium levels but also activates
bone-strengthening osteoblasts, effectively reversing the course of
osteoporosis. http://www.townsendletter.com/Chelation/chelation_extreme.htm
Cranton,
however, rejects the whole theory of removing calcium from plaques as outdated. http://www.drcranton.com/newhope.htm#IS%20IT%20TRUE He favors explanations involving more recent
research into the area of free radical pathology. Cranton explains that free radicals can
disrupt many other important molecules around them and have been implicated in
the promotion of atherosclerosis, cancer, and the basic decline in human health
with age. He says that EDTA binds to and
removes a particular form of iron that can catalyze the formation of free
radicals.
Cranton also
puts forth some other theories. Since
EDTA can bind to many different metals, it can trade one metal for another for
which it has a higher affinity as it travels through the body. This process theoretically has the potential
to move trace elements from areas of high concentration (which, according to
the cited research, can form in diseased tissue) to other areas where the
elements can be of benefit in facilitating healthy enzymatic activity. He also notes what is perhaps a more commonly
understood function of EDTA, the binding and removal of heavy metals that can
interfere with enzymatic processes (although in mainstream practice this treatment
is only used for known or suspected cases of heavy metal poisoning). http://www.drcranton.com/chelation/freeradical.htm
Yet another
explanation for cardiovascular improvements after treatment with EDTA is that
the removal of heavy metals leads to increased production of nitric oxide in
the endothelial cells, causing the arteries to relax and improving flow. http://www.gordonresearch.com/articles_iv_chelation/Shelton/homotoxicology_and_calcium_edta_chelation.html
These explanations mostly center on the cardiovascular
effects of ETDA, but its proponents think it is effective on a wide range of
conditions. One website explains how
EDTA can achieve such broad improvements by saying that once the arteries are
opened and the blood flow reestablished, other cells “downstream” will no
longer be deprived of nutrients or the opportunity to eliminate waste. The healing of these cells then ameliorates a
number of diseases. http://www.naturodoc.com/library/detox/EDTA-about.htm
Why are these
people putting out this information?
In addition to running a clinic that offers EDTA
chelation treatments, Dr. Cranton has also written one book and edited another
about the subject. His website has
numerous links to the pages where these books can be purchased. The information from the Townsend Letter article comes from a company that manufactures the
Oral Chelation and Age-Less formulas, and two others of the sites are unequivocally
trying to sell a product. Also, although
doctors who advocate and administer chelation therapy speak out against the
doctors and hospitals who profit from massively expensive cardiovascular
procedures, one must keep in mind that these doctors make their own profits
from chelation therapy, a full course of which can cost several thousand
dollars.
What does the scientific community say about chelation?
A search of the published scientific literature via
PubMed does not necessarily provide definitive answers to the many questions surrounding
EDTA chelation therapy. Article
conclusions range from approval of the therapy to (more commonly) disapproval,
with many articles indicating the need for further study before firmer
judgments can be made.
Effectiveness of EDTA chelation therapy in the treatment of
cardiovascular disease:
A recent literature review by Seely, Wu, and Mills (2005)
concluded that “[t]he best available evidence does not support the therapeutic
use of EDTA chelation therapy in the treatment of cardiovascular disease.” The authors examined five randomized controlled
trials and found that two supported the use of chelation and three did
not. The two positive trials, however,
were far smaller than the other three, and neither was completed as originally
planned; one ended early due to placebo group dropouts who weren’t seeing any
benefit, and in the other, the researcher broke the double blind code in view
of such “dramatic improvements” in what turned out to be the treatment
group. None of the other three studies
showed any significant benefit of EDTA chelation as compared to placebo.
The review also compiled data regarding adverse effects
in the studies, finding instances of faintness (6 treatment, 2 control),
hypocalcemia (11 treatment, 1 control), and one case in a treatment group of
“potential kidney toxicity.” Based on
outside information, the reviewers deemed EDTA to be safer than an alternative
such as coronary artery bypass grafting, but also noted that even small risks
are unreasonable if the therapy is not truly effective.
An animal study, on the other hand, showed some promise
for chelation therapy (Evans, Tariq, Sujata, McCann, and Sobki, 2001). Researchers fed rabbits a cholesterol-rich
diet, giving one group injections of EDTA and magnesium sulfate (a typical
ingredient in a chelation treatment).
The EDTA/magnesium sulfate reduced the increase of serum cholesterol,
triglyceride, and calcium levels and limited blockage of the aorta compared to
the control rabbits on the cholesterol diet.
Researchers took another group of cholesterol-fed rabbits, put them back
on a normal diet, and then gave some of them injections of EDTA/magnesium
sulfate. The treatment group had lower
levels of serum calcium and aortic blockage than the control group. These data showed a clear benefit from the
chelation therapy, although the researchers mentioned in the discussion that
the magnesium sulfate could have been responsible in whole or in part for the
favorable results.
A different animal study gave almost the opposite results
(O’Brien, Kelly, Dolphin, and Russell, 2000).
Researchers gave EDTA to rats who were genetically determined to be
obese, insulin-resistant, hypertriglyceridemic, and extremely prone to
atherosclerosis. When compared to the
control group of rats with similar genetic makeup, the cholesterol levels and
aortic health showed no improvement, while the triglyceride levels were
significantly higher. The researchers
concluded that “[c]helation therapy using intravenous EDTA has no
beneficial effects on the arterial lesions in the atherosclerotic JCR:LA-cp
rat. The increase in plasma triglyceride concentrations would be grounds for
concern in human patients.”
Research regarding the mechanisms of EDTA chelation:
Other research has yielded some information about the
possible mechanisms of EDTA in the body.
A study published in Free Radical
Biology and Medicine (Hininger et al., 2005) investigated whether the large
doses of vitamin C (an antioxidant) typically administered with EDTA therapy
might actually have a prooxidant effect.
The researchers gave two different groups of subjects EDTA with and
without 5 g vitamin C and found that indeed the biochemical measurements of
free radicals were markedly increased soon after therapy in the vitamin C group
compared to the group that did not receive vitamin C. However, over the course of 16 treatments,
the researchers found that despite the prooxidant activity directly following
each treatment, the long-term effects were antioxidant. They suggested that this therapy might be
beneficial to patients with heart disease and diabetes because the long term
effects involved protection against lipid peroxidation. They also noted that “[t]he effects of
multiple sessions of chelation therapy, without added vitamin C during the
chelation session, may lead to even more beneficial effects and need to be
determined.” While this study is far
from conclusive, it indicates that a component of the typical chelation
treatment is likely beneficial, and it suggests fairly specific further study
to continue learning about the potential antioxidant effects of EDTA.
Another article
(Guldager et al., 1993) provided evidence regarding the theory of how EDTA
might reverse osteoporosis (discussed above).
The double-blind study tested the effects of EDTA versus placebo on
serum parathyroid hormone (PTH) and biochemical markers of bone turnover. The researchers found that PTH secretion
increased significantly in the treatment group, and other biochemical tests
indicated bone “resorption” without “remodeling.” They concluded that “chelation therapy with
EDTA is accompanied by bone loss,” disproving the above theory.
Another article
(Anderson, Hubacek, Wyse, and Knudtson, 2003) looked for evidence to see
whether or not EDTA dilates arteries, which would support the theory of its
increasing nitric oxide production in the endothelial cells. This double-blind, randomized study
investigated the impact of infusions of EDTA with vitamins and minerals versus
placebo (vitamins and minerals only) on endothelium-dependent brachial artery
flow-mediated vasodilation in subjects with coronary artery disease who were
also being “optimally treated with proven therapies for atherosclerotic risk
factors.” The researchers found no
significant difference in flow-mediated vasodilation between the treatment and
placebo groups (although they did mention the possibility that the other drugs
being used to “optimally treat” the patients could have been so effective that
treatments with EDTA and/or vitamin C would not show any further benefit
regardless of their intrinsic value). In
the discussion of the results, it was suggested that perhaps the lack of
benefit from EDTA was because the small size of the EDTA molecule prevents its
completely binding to iron and negates the proposed antioxidant effect (which
is also integral to the proposed effect on nitric oxide production). This study provided support for neither the
theory of EDTA as an antioxidant nor the theory of EDTA’s increasing nitric
oxide production in endothelial cells.
Conclusions? 
Overall, the
published scientific literature through PubMed does not support the claims of
the many benefits of EDTA chelation therapy.
It must be noted that doctors and scientists on both sides of the debate
have serious problems with the methodology of those on the other side. The proponents of the therapy criticize the
designs of the trials that do not demonstrate any benefits as being biased
against the therapy, and they claim the results can still be reinterpreted to
support its efficacy. On his website,
Cranton criticizes several frequently-cited published studies for such serious shortcomings
as breaking of the double blind, small numbers of subjects, high dropout rate,
lack of consideration of confounding variables, and “data manipulation and
statistical irregularities” (http://www.drcranton.com/chelation/chelationcritics.htm). Chelation advocates also claim that the
medical establishment does not want the public to know about this treatment
because it would then lose its tremendous income from procedures such as bypass
grafting (although one must consider that they themselves profit from chelation
therapy).
Those against
the therapy (or at least reserving judgment) criticize the studies of the
proponents, saying that they do not provide valid scientific evidence because
most of them are small, without a control group for comparison, and much evidence
comes from case studies. For example,
the review by Seely et al. (see above) acknowledged that there were criticisms
against some of the studies in their review and even conceded that publication
bias could possibly have skewed their data (as chelation proponents say it
does). However, the researchers also
pointed out the weakness of most studies favoring chelation: lack of a control
group. They explained that several of the
studies in their review showed improvement in both the control and treatment
groups, and without a control the improvement would naturally be ascribed to
the treatment alone, thus producing a type I error.
Also, some of
the material published online by the proponents of chelation therapy (for
example http://www.drcranton.com/chelation/carter.htm)
seems to lower their credibility due to its emotionally charged nature, and
some of the claims (the reversal of gangrene, the >80% benefits) see to
violate common sense.
In view of this
controversy, more definitive conclusions may be reached in the relatively near
future. The National Institutes of
Health’s
Bibliography
(All materials
located online via PubMed and accessed when possible through the Vanderbilt
library electronic subscriptions)
Anderson, T.,
J., Hubacek, J., Wyse, D., G., & Knudtson, M. L. (2003).
Effect of Chelation Therapy on Endothelial Function in Patients With
Coronary Artery Disease: PATCH Substudy.
Journal of the
Evans, D. A., Tariq,
M., Sujata, B., McCann, G., & Sobki, S.
(2001). The effects of magnesium
sulphate and EDTA in the hypercholesterolaemic rabbit. Diabetes, Obesity and Metabolism, 3(6),
417.
Guldager B.,
Brixen K. T., Jorgensen S. J., Nielsen H. K., Mosekilde L., & Jelnes
R.. (1993). Effects
of intravenous EDTA treatment on serum parathyroid hormone (1-84) and
biochemical markers of bone turnover. Danish Medical Bulletin, 40(5),
627-630.
Hininger,
O’Brien, S. F., Kelly, S. E., Dolphin, P. J., and
Russell, J. C. (2000). Chelation therapy in the JCR:LA-cp rat:
experimental assessment of a putative antiatherosclerotic treatment. Clinical
and investigative medicine, 23(2), 124-131.
Seely, D. M. R.,
Wu, P., & Mills, E. J. (2005). EDTA
chelation therapy for cardiovascular disease: a systematic review. BioMed
Central Cardiovascular Disorders, 5, 32.
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