Consumers sue Starbucks over sugar free protein drink claims

Consumers filed a proposed class action in Seattle federal court accusing Starbucks of misleading buyers about sugar free claims tied to eight protein beverages, The Korea Times reported.

The lawsuit centers on how companies describe nutrition claims as more Americans look to cut sugar, with the complaint saying 75 percent of Americans want to reduce or eliminate sugar consumption.

According to The Korea Times, the proposed class action was filed Friday in Seattle federal court and challenges eight Starbucks protein beverages. The consumers allege the drinks were marketed with sugar free claims even though they contain lactose, a sugar that occurs naturally in milk.

The complaint says federal rules do not allow a beverage to be described that way if it contains more than 0.5 grams of sugar per 12-ounce serving, The Korea Times reported. The consumers allege reasonable buyers would not expect 13 to 21 grams of sugar in a 20- or 24-ounce venti serving.

The lawsuit seeks unspecified damages and cites alleged false advertising and violations of various state consumer protection laws, according to The Korea Times. The complaint also alleges Starbucks did not provide required disclaimers saying the beverages are not low-calorie foods or intended for weight control.

Starbucks denied the allegations. "Starbucks has consistently and clearly provided information about its protein beverages, sugar-free options, customization choices, and nutritional content across product announcements, menus, marketing materials, Starbucks.com and the Starbucks app, and we intend to vigorously defend ourselves," a Starbucks spokesperson said in an email, according to The Korea Times.

The Korea Times reported that Starbucks' website describes the beverages as protein-focused and with no added sugar, while also listing sugar content. The website lists 270 to 340 calories for venti servings.

Starbucks launched the beverages in September 2025 as part of an updated menu, according to The Korea Times.