CREATINE UPDATE
MDA Experts Say, 'Take Supplements Only Under Doctor's Care'
On Jan. 23, the French equivalent of the U.S. Food and Drug Administration (Agence Francaise de Securite Sanitaire des Aliments, or AFSSA) issued an advisory about potential health risks, including a possible cancer risk, in taking creatine, a dietary supplement available over the counter in the United States and widely used as a purported muscle-building agent.
MDA-supported neuromuscular disease experts don't believe there's evidence of health risks with creatine for people taking it in clinical trials for neuromuscular diseases or under the supervision of their physicians.
Mark Tarnopolsky, an MDA-supported physician-scientist who's conducting a study of creatine in Duchenne, Becker and myotonic muscular dystrophies (MMD) in Hamilton, Ontario, Canada, said he knows of no data supporting the alleged link between creatine supplementation and cancer.
"This is not supported by the literature, and it is unfortunate that medical misinformation can be spread throughout the world so rapidly," Tarnopolsky said. "The statement regarding a 'link' between creatine and cancer comes from a hypothesis published in the journal Medical Hypotheses, where 20 grams of creatine increased the concentration of a chemical that has been linked to cancer. There are no studies showing that this degree of increase in humans is linked to cancer, and this is very far from showing a link between creatine ingestion and cancer."
MDA is sponsoring four trials to test the ability of creatine to decrease disease symptoms in amyotrophic lateral sclerosis (ALS) or muscular dystrophy (MD).
The statement released by the French doesn't address the use of creatine by people with neuromuscular disorders who are under medical supervision. It's aimed at healthy subjects attempting to increase their athletic performance.
The statement said that "adverse incidents" involving the digestive, muscular and cardiovascular systems of people taking high dosages of creatine have occurred, and also warned that impurities could exist in creatine that's marketed to consumers.
Reports by two English-language news services implied that the French had performed a cancer linkage study. In fact, the French statement said only that, under certain conditions, carcinogenic (cancer-causing) potential could not be ruled out. The AFSSA statement said preliminary experimental evidence exists of carcinogenic effects when creatine interacts with simple sugars or amino acids.
Diana Escolar, a physician who heads an MDA-funded study of creatine and glutamine in Duchenne MD at Children's National Medical Center in Washington, said she would look into the matter. She noted that in her extensive research on creatine before starting the trial, "nowhere have I ever seen carcinogenesis."
Erik Henricson, the study coordinator, is responsible for making sure that all centers involved in the trial meet FDA requirements. He said that any human trial involves very careful tracking of research, regulatory agency reports and reactions of trial participants. That close surveillance, he said, makes it advisable to take untested drugs only in a clinical trial setting.
Henricson said there are no absolute guarantees that a substance being tested in a clinical trial is completely safe, but that "people should understand that careful review and safety monitory processes are set up to protect them from adverse events."
"If someone is taking a nutritional supplement," he said, "it should be under the direction of a physician, who can order lab tests and look at kidney and liver and other vital functions. If you're taking something, you should be able to walk into your doctor and say that you need to be checked periodically."
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