Coenzyme Q10, a popular supplement said to improve heart function, was shown ineffective as a heart helper in a University of Maryland study. The study contradicts findings of earlier trials.
This new research surprised Judy Martin, fifty-one, who has taken 30 mg of CoQ10 daily for nearly ten years.
“I always took it for the fact that it would strengthen my heart muscle,” says Martin, who learned about the then lesser-known supplement in 1989 and began taking it as a preventive measure. Her family has a history of heart disease.
Martin and others with a risk for heart problems could pay up to $50 a month for CoQ10, a natural enzyme produced by our bodies. Found in the mitochondria, the enzyme is responsible for producing adenosine triphosphate (ATP), the cell’s basic energy source.
CoQ10 has been shown in previous trials to improve heart function and relieve the symptoms associated with congestive heart failure, the inability of the heart to pump adequate amounts of blood to the lungs and body. CoQ10 is thought to strengthen the health of the cardiac muscle, and has been found in depleted concentrations in the cardiac cells of advanced heart-failure patients.
Stephen Gottlieb, M.D., lead researcher for the study, chose to evaluate CoQ10 when many of his patients began self-prescribing the supplement. He and other researchers presented their findings in November 1999 at the American Heart Association’s Seventy-second Annual Scientific Sessions.
The double-blind, randomized, placebo-controlled study found no benefit from CoQ10 for patients with congestive heart failure. For six months, forty-six moderately to severely ill heart-failure patients took either a placebo or 200 mg of CoQ10 daily along with their regular heart medication. Researchers then tested participants’ cardiac performance and exercise duration.
Alan Gaby, M.D., professor of nutrition at Bastyr University, questioned the participants’ nutritional status in the University of Maryland study. The study did not involve addressing the effect of supplementation of vitamins and minerals.
“Heart failure is frequently associated with poor nutritional status,” he says. “Because patients don’t eat well, they ‘burn up’ nutrients more rapidly, and they take nutrient-depleting diuretics.”
Gaby says that many other nutrients are necessary for heart health, including magnesium, taurine, pantothenic acid, thiamine, and vitamin E. If patients are low in these or other nutrients, CoQ10 may not be able to do its job adequately, he says.
Gaby recommends that his patients take CoQ10 in combination with other nutrients. Many of his patients have shown improvement—some, marked improvement—after using the supplement.
Overall, the patients were clinically free of any evidence of malnutrition, says Michael Fisher, M.D., professor of medicine and director of clinical cardiology at the University of Maryland.
Fisher takes into account the reports that confirm the benefit of CoQ10, saying that the researchers are not trying to say CoQ10 could not have any benefit, but clarifies that in their research, no measurable overall improvement was made in their congestive heart failure patients.
“As is usual, carefully done trials are key to developing an understanding of both the benefits and the limitations of therapy,” he says, “as well as pointing to additional possible issues to be studied.”
Martin, who has taken a break from taking the supplement, still firmly believes in CoQ10 for heart patients, using her father as an example that CoQ10 helps the heart.
“Most patients who have had heart bypass surgeries don’t live more than ten years,” she says. Her father, now sixty-nine, had heart bypass surgery in 1980. “His doctors call him a walking miracle,” she says. Martin’s father takes other supplements in addition to CoQ10, such as a multivitamin, calcium, a B complex, cayenne, and garlic.
Gottlieb says he isn’t planning any more studies on CoQ10. He says that taking CoQ10 probably has minimal risk and is letting his patients know of the study’s results and allowing them to decide if the supplement is worth their money.