The U.S. Food and Drug Administration on May 8th asked the 10th U.S. Circuit Court of Appeals to restore its ban on the weight loss aid ephedra, arguing that the federal judge who made the ruling misunderstood the law.

The FDA contended that U.S. District Judge Tena Campbell in Salt Lake City did not understand the law or the FDA’s duties in regulating dietary supplements when she ruled last year that the ban could not be enforced on diet pills containing 10 milligrams or less of ephedra.

The agency banned ephedra two years ago after the dietary supplement was linked to dozens of deaths and thousands of reports of problems such as heart attacks or increased blood pressure. The FDA ruled that ephedra, taken in any amount, poses an unreasonable risk of illness or injury.

One company that manufacturered ephedra-containing products, Nutraceutical Corp., sued to overturn the ban.

But FDA lawyers told the Circuit Court of Appeals that federal law does in fact give it the authority to act to ban the use of a substance it believes is harmful.

While several companies advertise ephedra products on the internet, Nutraceutical has chosen not to reintroduce supplements containing ephedra pending the outcome of the FDA's appeal.

Jonathan Emord, the lawyer representing Nutraceutical, said that reintroduction has been rendered difficult in any case because the FDA rule has effectively destroyed sources of ephedra in the United States.