In 2017, several plaintiffs began bringing lawsuits in California and New York premised on the theory that “diet” sodas — i.e., sodas sweetened with zero-calorie artificial sweeteners rather than sugar — were mislabeled because the sodas falsely suggested they would help consumers lose weight, even though aspartame and other artificial sweeteners are supposedly associated with weight gain. Courts have routinely dismissed these lawsuits on one of two grounds:
- Some courts have concluded that this theory of deception is implausible because reasonable consumers understand the term “diet” to mean that the soda has zero calories, not that it will help them lose weight. See, e.g., Geffner v. Coca-Cola Co., 928 F.3d 198, 200 (2d Cir. 2019) (“[T]he “diet” label refers specifically to the drink’s low caloric content; it does not convey a more general weight loss promise.”); Becerra v. Coca-Cola Co., No. 17-5916, 2018 WL 1070823, at *3 (N.D. Cal. Feb. 27, 2018) (“Reasonable consumers would understand that Diet Coke merely deletes the calories usually present in regular Coke, and that the caloric reduction will lead to weight loss only as part of an overall sensible diet and exercise regimen dependent on individual metabolism.”).
- Other courts have dismissed these lawsuits on the basis that the scientific literature cited by the plaintiffs does not support a causal relationship between zero-calorie sweeteners and weight gain. See, e.g., Excevarria v. Dr. Pepper Snapple Grp., Inc., 764 F. App’x 108, 110 (2d Cir. 2019) (affirming dismissal of lawsuit challenging labeling of Diet Dr. Pepper, as “[n]one of the studies cited . . . establish a causal relationship between aspartame and weight gain”).
The Ninth Circuit recently joined the chorus of courts that have rejected this theory of deception. In Becerra v. Dr. Pepper/Seven Up, Inc., the district court dismissed a lawsuit alleging that Diet Dr. Pepper was mislabeled as a “diet” soda, both because the plaintiff had not alleged that consumers construed the term “diet” as a representation about weight loss and because the plaintiff had not sufficiently alleged that aspartame is associated with weight gain. On December 30, 2019, the Ninth Circuit issued a published decision affirming the dismissal of this lawsuit. Becerra v. Dr. Pepper/Seven Up, Inc. --- F.3d ----, 2019 WL 7287554 (9th Cir. 2019).