Starbucks has been sued by consumers who said the coffee chain falsely advertised eight protein beverages as “sugar-free” because they contain lactose, a naturally occurring sugar in milk.
According to a proposed class action filed on Friday, reasonable consumers would not expect the beverages to contain 13 to 21 grams of sugar per 20- or 24-ounce “venti” serving.
Federal law prohibits Starbucks from using “sugar-free” to describe beverages containing more than 0.5 grams of sugar per 12-ounce serving, the complaint said.
Consumers accused Starbucks of trying to capitalize on the desire of 75% of Americans to reduce or eliminate sugar consumption. They also said Starbucks failed to provide federally required disclaimers that the protein beverages are not low-calorie food or meant for weight control.
A Starbucks spokesperson said in an email that the claims have no merit.
“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,” the spokesperson said.
A lawyer for the consumers did not immediately respond to requests for additional comment. The complaint in Seattle federal court seeks unspecified damages for false advertising and violations of various state consumer protection laws.
Food producers are regularly sued for alleged false advertising, including in dozens of recent cases challenging “sugar-free” or “zero sugar” claims for products containing a sugar substitute known as allulose.
The eight Starbucks beverages are Sugar-Free Vanilla Protein Latte, Sugar-Free Caramel Protein Latte, Sugar-Free Vanilla Protein Matcha, Sugar-Free Caramel Protein Matcha, and equivalent versions containing ice.
Starbucks’ website says the beverages are “protein-packed” with “no added sugar,” and venti servings contain between 270 and 340 calories. The website also shows that the beverages contain sugars. Starbucks launched the beverages in September 2025 as part of its “Back to Starbucks” updated menu. — Reuters
