Shares of dietary supplement retailers tumbled in heavy trading volume on Tuesday, spurring a surge in options hedging activity for those stocks even though fears they would be mentioned in a U.S. Department of Justice lawsuit did not materialize. GNC Holdings’ shares tumbled as much as 27.1 percent to hit their lowest in four years, but closed 6.4 percent lower at $29.07. The DOJ called a press conference at noon Eastern (1500 GMT) about criminal and civil actions aimed at stemming the sale of unproven nutritional supplements.

(Reuters) – Several federal agencies including the U.S. Departmentof Justice will announce criminal and civil actions on Tuesday related to unlawful advertising and sale of dietary supplements. The U.S. Attorney’s Office in Los Angeles said in an advisory that a joint press conference would be held to discuss cases filed in Los Angeles. GNC Holdings Inc fell 24 percent though the shares later rebounded a bit and were trading at $26.78.