The Food and Drug Administration says a federal judge who lifted the ban on dietary supplements containing low doses of the weight-loss aid ephedra misunderstood the law.
The FDA is in court in an effort to restore the ban.
An attorney for a Utah company argues that if the judge's decision is overturned, the FDA could ban virtually any substance on the market it determines is harmful in large doses.
The attorneys told a three-judge panel of the Tenth U.S. Circuit Court of Appeals in Denver that could even include vitamin C or peanut butter.
Nutraceutical Corporation challenged the ban and a federal judge ruled last year the ban could not be enforced against supplements containing small doses of ephedra.
Ephedra was banned two years ago after being linked to dozens of deaths and possible heart and blood pressure problems.