What is chelation therapy?

Overview

When medical researchers first investigated the phenomenon known as hardening
of the arteries (closely related to atherosclerosis), they discovered that
the damaged, brittle vessels found in people with heart disease
were lined with calcium deposits. This finding inspired the notion that calcium
deposits were the cause of the problem.

Some early researchers investigated the possible therapeutic effect of removing such deposits. However, subsequent research indicated that the calcium deposits of atherosclerosis were a symptom rather than a cause, and mainstream interest turned elsewhere. Certain physicians nonetheless maintained an interest in removing calcium; thus, chelation therapy was born.

Chelation therapy for heart disease consists of intravenous infusions of a chemical called ethylenediaminetetraacetic acid (EDTA). This synthetic substance is used in conventional medicine to remove heavy metals, such as lead, from the body, but it also has an effect on calcium, which is why it came into use in chelation therapy.

Proponents claim that EDTA chelation is an effective alternative to heart
surgery and that it also offers many other health benefits. To support these
claims, proponents cite numerous anecdotes of cures apparently brought about by
its use. However, anecdotes cannot possibly prove a treatment effective. Only
double-blind,
placebo-controlled trials can do so, and such studies have
failed to find chelation therapy effective.

In 2000, a highly respected researcher reviewed the literature on chelation therapy and concluded that
The most striking finding is the almost total lack of convincing evidence for efficacy. . . . Only 2 controlled clinical trials were located. They provide no evidence that chelation therapy is efficacious beyond a powerful placebo effect. . . . Given the potential of chelation therapy to cause severe adverse effects, this treatment should now be considered obsolete.

Subsequent to this review, a well-designed study compared chelation therapy to placebo in eighty-four people with coronary artery disease. People receiving EDTA chelation showed improvement; however, those receiving placebo also improved, and did so to the same extent. This finding is a reminder of why double-blind, placebo-controlled studies are necessary to establish the effectiveness of a treatment. If researchers had performed this study without a placebo group, they might have concluded that EDTA chelation really works. Instead, the fact that the same level of benefits was seen in the fake-treatment group indicates that chelation therapy does not work.

Another double-blind study evaluated the potential benefits of chelation therapy when added to conventional therapy in the treatment of people with coronary artery disease. Researchers were looking for improvements in the ability of a blood vessel in the arm (the brachial artery) to dilate, but they did not find any. However, this study had several limitations in its design, making its results less meaningful than they might have been.

Safety Issues

EDTA chelation not only appears to be ineffective; it also may present some safety risks. This treatment is generally given in a series of ten to thirty sessions. If the practitioner fails to take proper precautions, severe adverse consequences, such as kidney damage, may result. While it appears to be the case that properly performed chelation therapy is unlikely to cause harm, there is no justification for using such an invasive method in the absence of evidence that it will help.

Anderson, T. J., et al. “Effect of Chelation Therapy on Endothelial Function in Patients with Coronary Artery Disease.” Journal of the American College of Cardiology 41 (2003): 420-425.

Ernst, E. “Chelation Therapy for Coronary Heart Disease: An Overview of All Clinical Investigations.” American Heart Journal 140 (2000): 4-5.

Knudtson, M. L., et al. “Chelation Therapy for Ischemic Heart Disease.” Journal of the American Medical Association 287 (2002): 481-486.