diet pepsiLast May on the eve of Memorial Day, we wrote about a Southern District of New York decision dismissing a class action against Pepsi-Cola. On Friday, March 15, a three-judge panel of the U.S. Court of Appeals for the Second Circuit issued a Summary Order (which has no precedential value) affirming the lower court’s decision.

The plaintiff in Manuel v. Pepsi-Cola Co. alleged that a reasonable consumer would conclude that the use of the term “diet” in Diet Pepsi meant that the beverage assisted in weight loss. Because the non-nutritive sweeteners Pepsi used as substitutes for sugar led to weight gain, the plaintiffs argued, use of the term “diet” was misleading in violation of state consumer-protection laws. The trial court held that no reasonable consumer would interpret “diet” in “Diet Pepsi” in the same manner as the plaintiff argued it meant. In addition, the court found that the studies the plaintiff cited in support of her claim that sugar substitutes caused weigh gain in fact offered no such support.

The Second Circuit concluded that even if a reasonable consumer would interpret the “diet” in Diet Pepsi to mean consumption=weight loss, the studies the plaintiff cited did not establish a causal relationship between sugar substitutes and weight gain “to a degree that is sufficiently strong.” The appeals court also affirmed the lower court’s decision to dismiss Manuel’s complaint with prejudice.