Starbucks Sued Over ‘Sugar-Free’ Protein Drink Labeling

A federal lawsuit filed in Washington state accuses Starbucks of violating Food and Drug Administration labeling rules by marketing eight protein beverages as “Sugar-Free” despite the drinks containing up to 21 grams of sugar per serving.

The proposed class-action complaint, lodged Friday in the U.S. District Court for the Western District of Washington, targets the coffee chain’s protein drink lineup introduced in September 2025. The products — hot and iced Sugar-Free Vanilla and Caramel Protein Lattes and Protein Matchas — rely on milk as a base ingredient. Milk naturally contains lactose, a form of sugar that the FDA counts toward total sugar content regardless of whether a manufacturer added it during preparation.

Under Title 21 of the Code of Federal Regulations, a product may only carry a “sugar free” claim if it contains less than 0.5 grams of total sugar per reference amount customarily consumed and per labeled serving. A venti-sized Sugar-Free Caramel Protein Matcha contains 21 grams of sugar, while the Sugar-Free Vanilla Protein Matcha contains 20 grams, according to nutritional data cited in the complaint. Even smaller sizes would far exceed the half-gram threshold because an eight-ounce cup of standard dairy milk alone contains roughly 12 grams of naturally occurring lactose.

The distinction between total sugar and added sugar sits at the core of the dispute. Starbucks has described the beverages as containing “no added sugar,” a phrase governed by separate FDA standards that permit manufacturers to highlight the absence of syrups or sweeteners even when natural sugars are present. However, the plaintiffs argue that embedding the term “Sugar-Free” directly into the product names crosses the line from describing added ingredients into making an impermissible absolute claim about total sugar content.

“This case is about false and misleading product names. It is not about missing nutritional information,” the complaint states, acknowledging that Starbucks publishes full nutritional data on its menus, website, and mobile app.

Beyond the sugar thresholds, the lawsuit flags a secondary regulatory requirement. FDA rules mandate that any food bearing a “sugar free” claim but failing to qualify as “low calorie” or “reduced calorie” must display a prominent disclaimer stating the product is not intended for weight control. The venti protein drinks contain between 270 and 340 calories, well above the 40-calorie-per-serving limit required for a “low calorie” designation. The plaintiffs allege Starbucks failed to provide the required caloric disclaimer alongside the sugar-free branding.

Consumers Michael Walsh of California, Anne Legnini of New York, and Elna Potter of Washington brought the suit. They are seeking to represent a nationwide class of purchasers, with alternative state-specific classes proposed for California, New York, and Washington. The claims span consumer protection statutes, false advertising laws, breach of implied warranty, and unjust enrichment. The plaintiffs are requesting damages, restitution, and an injunction preventing Starbucks from using the “Sugar-Free” designation unless the beverages meet federal criteria.

Starbucks rejected the allegations outright. “We believe these claims have no merit,” a company spokesperson said. “Starbucks has consistently and clearly provided information about our 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 in this matter.”

The September 2025 rollout of the protein beverages was part of a broader industry pivot. Major chains including Dunkin’, Jamba, and Smoothie King have expanded high-protein offerings over the past two years to capture health-conscious consumers willing to pay premium prices for functional ingredients. Starbucks positioned its protein line as a customizable option where patrons could select sugar-free flavor profiles while adding whey or plant-based protein powder.

Food labeling litigation has become a persistent operational risk for major restaurant chains and packaged goods manufacturers. Federal courts have seen a surge in lawsuits targeting terms like “natural,” “healthy,” and “zero sugar” over the past decade. Unlike FDA enforcement actions, which often move slowly and prioritize public health emergencies, private class actions under state consumer protection laws can force rapid menu changes and costly settlements. In 2023 and 2024, several beverage companies quietly reformulated products or altered packaging after similar suits challenged their sugar-related marketing.

Shares of Starbucks Corp. (SBUX) traded at $94.43, down 0.30%, following the filing. The case remains in its preliminary stages, and no judge has yet ruled on class certification or the merits of the regulatory arguments.