In Brown v. GNC Corp., the Fourth Circuit offered a novel solution to the truth-in-advertising dilemma that plagued the dietary supplement industry. Plaintiffs alleged that claims made in connection with defendant’s joint health supplements were false because the “vast weight of competent and reliable scientific evidence” did not support such representations. The Fourth Circuit rejected this allegation of literal falsity, which hinges instead on the “existence (or not) of scientific consensus.” To survive a motion to dismiss, plaintiffs must allege that all reasonable experts in the field agree that the representations are false. This holding generated criticism from prominent academics, who submitted an amicus brief favoring an alternative result. This Note argues that the Fourth Circuit’s unanimous holding in GNC is the preferred solution to the age-old truth-in-advertising question, particularly during a period of scientific uncertainty. In reaching this conclusion, this Note surveys the existing patchwork of advertising laws, details the factual background of the GNC case, and addresses problematic aspects of the amicus brief. It concludes by describing the merits of the Fourth Circuit’s decision, which has positive implications for consumers and manufacturers alike.