Worst Pills, Best Pills

An expert, independent second opinion on more than 1,800 prescription drugs, over-the-counter medications, and supplements

A Review of Amino Acid Dietary Supplement L-Arginine Use After a Heart Attack

Worst Pills, Best Pills Newsletter article April, 2006

A “gold standard” randomized controlled clinical trial published in the Jan. 4, 2006 Journal of the American Medical Association concluded that the amino acid l-arginine, sold widely as a dietary supplement, should not be used after a heart attack. The researchers were from Johns Hopkins and the University of Maryland. The trial is known as the Vascular Interaction With Age in Myocardial Infarction Randomized Clinical Trial, or VINTAGE MI. The National Heart, Lung, and Blood Institute, a part...

A “gold standard” randomized controlled clinical trial published in the Jan. 4, 2006 Journal of the American Medical Association concluded that the amino acid l-arginine, sold widely as a dietary supplement, should not be used after a heart attack. The researchers were from Johns Hopkins and the University of Maryland. The trial is known as the Vascular Interaction With Age in Myocardial Infarction Randomized Clinical Trial, or VINTAGE MI. The National Heart, Lung, and Blood Institute, a part of the National Institutes of Health, funded the trial. A myocardial infarction is the medical term for a heart attack.

The purpose of the research was to test the theory that l-arginine would reduce the stiffness of blood vessels, a “hallmark” of aging, that should aid in the heart’s ability to pump blood. The study was conducted in patients with a specific type of heart attack called a ST-segment elevation myocardial infarction or STEMI. The ST segment refers to a section of an electrocardiogram (EKG or ECG) tracing.

The study involved 153 patients who had suffered from one incident of STEMI. The average age of these patients was 60 years and 68 percent of them were male. The patients were randomly assigned to receive dosages of l-arginine of up to three grams three times a day or a matching placebo for six months. Of these 153 patients, 78 were given l-arginine and 75 were assigned to receive the placebo.  

The committee that was responsible for monitoring patients’ safety in the VINTAGE MI trial, called the Data Safety Monitoring Committee, stopped the study after the death of six patients (8.6 percent) taking l-arginine versus no deaths in the placebo group.

The researchers concluded that:

L-arginine should not be recommended following acute myocardial infarction [heart attack].

L-arginine is promoted heavily on the Internet. One l-arginine peddler claims that “This product produces more benefits than any other pharmaceutical or nutraceutical agent ever discovered.” The site lists a litany of purported benefits, including claims that it:

  • Reduces the risk of vascular and heart disease
  • Reduces body fat
  • Promotes body fat burning
  • Improves immune function
  • Natural alternative for Viagra and also works for women
  • Builds muscle mass
  • Increases bone density
  • Reduces healing time of injuries particularly bones when they break as in Osteoporosis
  • Anti-oxidant properties
  • Increases energy levels
  • Reduces blood pressure
  • Reduces risk of heart disease, stroke and cholesterol
  • Reduces clogged arteries
  • Increases sperm count and motility by 250% in 2 weeks
  • Maintains healthy blood-sugar levels
  • Reduces the risk of cardiovascular heart disease
  • Achieves and maintains erections
  • Increases fertility and orgasm in women
  • Improves cardio-vascular disease that is already prevalent.

According to this Web site, the world apparently needs only one treatment, l-arginine, to conquer many of mankind’s ills. If it is too good to be true, it probably is: as with all things, caveat emptor, let the buyer beware.  

Under archaic U.S. laws, dietary supplements, such as l-arginine, can be sold without having to show that they are safe or that they will do what their producers say they will do. They can be produced in factories that do not follow Good Manufacturing Practice guidelines. For all practical purposes, dietary producers operate outside of the law, because there are no laws or regulations that protect U.S. consumers from dietary supplement hucksters. The windfall profits that come from being able to market an unproven substance for any use under the sun pay for an army of Washington, D.C. lobbyists who work to protect their unregulated status.

In the U.S., consumers face, on their own, the potential harms of unregulated remedies that is reminiscent of the snake oil era that existed before the turn of the twentieth century.  

Clearly, a dangerous hoax  is being perpetrated against the American public as a result of the Dietary Supplement Health and Education Act (DSHEA). This law, passed by Congress in 1994, deregulated the dietary supplement industry. It is shameful that U.S. taxpayers fund trials like VINTAGE MI to determine if a dietary supplement may benefit or harm the public (in this case it was harm) while the producers of these products can continue to promote outlandish claims of effectiveness, in the absence of any credible evidence of benefit, but in the presence of huge profits.  The responsibility and funding to demonstrate safety and to show a health benefit should have come from those who are benefiting economically: l-arginine producers.

A basic American right is a market place free of products that make unsubstantiated claims and products produced in factories that do not have to show that they meet minimal manufacturing safeguards. This right will continue to be violated until DSHEA is repealed.  

What Should You Do  

You should not use l-arginine after a heart attack.

You should not use any dietary supplement. There is no credible evidence that these products are what they claim to be or can do what their producers say they can do.