Chelation Therapy
Chester J. Zelasko, Ph.D. |
January 26, 2007
In the past several
months, we’ve gotten a number of questions about the effectiveness of
chelation therapy to reduce the risk of heart disease. The claims for
chelation therapy run from removing plaque from arteries to lowering
cholesterol to detoxifying the body.
What is chelation therapy and what does the science say? This Newsletter
answers those questions.
What is chelation therapy?
Chelation therapy involves the use of a chemical agent that will bind with
some noxious substance in the body; the purpose is to eliminate the
substance from the body. This process has been used to remove lead and other
heavy metals and is still used to some degree for that purpose. However, in
the 1960s, physicians treated heart attack patients with a specific
chelating agent and claimed to have reversed the symptoms. Over the past 40
years, chelation therapy has been the object of numerous research trials,
some well-designed and some not. The results have been less than positive.
The chelating agent used was ethylene diamine tetraacetic acid (EDTA), and
it’s still used today. The typical course of chelation therapy for
cardiovascular disease was a three- to four-hour infusion of EDTA, usually
mixed with antioxidants. Treatments took place weekly for 20 weeks or more.
In a randomized clinical trial of subjects who had been diagnosed with
cardiovascular disease for over 21 years, twice-weekly chelation sessions
for 15 weeks and then monthly for another three months resulted in no change
in any measures of cardiovascular disease when compared with controls (1).
Another study tested the ability of chelation therapy to improve blood flow
by allowing blood vessels to dilate (2). In a double-blind,
placebo-controlled trial, researchers used 33 sessions of chelation therapy
to examine changes in blood flow between the control and experimental
groups. There were none.
In a recent review article, researchers attempted to perform a meta-analysis
of all published clinical trials of chelation therapy (3). Out of 388
articles found by examining at least seven medical data bases, only 14
studies could be found that met acceptable scientific standards. Of those,
only seven were pooled for analysis due to duplication. The analyses could
find no support for improvement in cardiovascular disease after chelation
therapy.
Given the lack of evidence, one would think that would end the story. It
does not. The Trial to Assess Chelation Therapy is now underway through the
National Center for Complementary and Alternative Medicine of the National
Institute of Health. The TACT study will include over 2,300 patients and is
currently recruiting patients over 50 who have had heart attacks. In a
published interview, study director Dr. Gervasio Lamas, states that, "What
we're trying to figure out is if chelation therapy--as it's been practiced
now for many years in the community--is really beneficial. And by
‘beneficial’ what I mean is does it prevent heart attacks? Does it prevent
having procedures to open coronary arteries? Does it prevent strokes? Does
it keep patients healthier? That's really what we need to figure out." (4)
Chelation in a Pill
Many products sold as dietary supplements contain EDTA as well as other
antioxidants that claim to work the same as EDTA infusion. A thorough review
of the science results in not a single study demonstrating efficacy of using
oral chelation for reducing cardiovascular disease.
Using EDTA as a supplement assumes that it will pass through the gut whole
and be absorbed whole. Because EDTA is a protein, that’s unlikely. The
assumptions continue--that the quantity of the active ingredients will be
sufficient to actually chelate the arteries. Again, there’s no evidence that
it will.
The Risks of Chelation Therapy
While rare, deaths can occur from chelation therapy due to the alterations
of electrolyte balance. When noxious metals such as mercury and lead are not
present, the EDTA will attract other positively charged ions such as
calcium. In fact, one theory is that it’s the removal of calcium from
arterial walls that reduces the plaque from arteries. Altering the calcium
balance can result in kidney damage and death. The Mortality and
Morbidity Weekly Report in 2006 reported three deaths in three states
as a result of chelation therapy (5). In one case, a woman with
cardiovascular disease had undergone the treatment before. In another, a
young child with autism was undergoing chelation therapy to remove toxins.
Chelation Therapy--Yes or No?
Based on the scientific evidence, the answer is "not yet" and certainly
there’s no benefit to chelation via supplement. When the TACT study is
complete, it will give more insight into whether the treatment is effective
for heart disease.
It’s easy to just say "Don’t do that," but many people have found they feel
better after chelation therapy. Feeling better doesn’t mean you have really
reduced your risk of disease. Should you do it anyway? That’s for you to
answer for yourself. Before I let anyone infuse my body with chemicals
repeatedly for weeks at a time, I’d have to be very sure they knew what they
were doing and would guarantee an improvement in some cardiovascular
measurement.
Until then, reducing heart disease will just have to be done the old
fashioned way: eat better, lose weight, exercise regularly, and don’t smoke.
Period.
References:
- Knudtson ML, et al. Chelation therapy for ischemic heart disease: a
randomized controlled trial. JAMA. 2002; 287(4):481-6.
- Anderson TJ et al. Effect of chelation therapy on endothelial
function in patients with coronary artery disease: PATCH substudy. J Am
Coll Cardiol. 2003;41(3):420-5.
- Dugald MR et al. EDTA chelation therapy for cardiovascular disease:
a systematic review. BMC Cardiovascular Disorders 2005, 5:32.
-
http://nccam.nih.gov/health/chelation/
- MMWR March 3, 2006. Deaths Associated with Hypocalcemia from
Chelation Therapy --- Texas, Pennsylvania, and Oregon, 2003--2005. MMWR
55(08);204-207.
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