Celsius sued over energy drink labels claiming the drinks burn body fat and accelerate metabolism

Estimated reading time: 9 minutes.

Key facts

• What happened: A Washington shopper filed a proposed class action on October 26, 2026, alleging that Celsius energy drink labels reading "Accelerates Metabolism" and "Burns Body Fat" mislead consumers.
• The case: Nielsen v. Celsius Holdings, Inc. and Celsius, Inc., No. 2:26-cv-04113, in the U.S. District Court for the Western District of Washington in Seattle.
• The products: 19 Celsius drinks and On-the-Go products listed in the complaint, including Essential Energy Sparkling and Fizz Free flavors.
• The core allegation: The plaintiff says the six studies Celsius cites to support its claims were all funded by Celsius and measured short-term effects over hours, not fat loss.
• Who the case would cover: People who bought the listed products in Washington from October 26, 2022, through trial, if a judge certifies the class.
• Status: Newly filed. Celsius did not immediately respond to a request for comment from Courthouse News. There is no settlement, refund or claim form.

In this article

• What the lawsuit claims
• The products named in the complaint
• The science dispute
• What healthwashing means
• The legal claims
• Timeline
• Who may be affected and what you can do now
• What remains unresolved
• What happens next
• Frequently asked questions

What the lawsuit claims

The plaintiff, Annabelle Nielsen, lives in Bothell, in King County, Washington. According to the complaint, she bought a wide range of Celsius drinks from Amazon, Target, 7-Eleven, Costco and Fred Meyer between about December 2024 and September 2026. She says she relied on the front-of-label claims when she bought them and would not have bought them, or would have paid less, if she had known the claims were misleading.

The lawsuit focuses on three phrases printed on the front of the cans and packets: "Accelerates Metabolism," "Burns Body Fat" and "Live Fit." The complaint calls these the "Wellness Claims." It argues that a reasonable shopper would read them to mean the drink, by itself, speeds up metabolism and burns fat.

The complaint says the back of the label tells a more limited story. It quotes small print saying the product "helps maintain the bodies' regular metabolic function" and that "CELSIUS alone does not produce weight loss in the absence of a healthy diet and moderate exercise." The plaintiff argues that this disclaimer does not cure what she says is a misleading front label.

The defendants are Celsius Holdings, Inc. and its subsidiary Celsius, Inc. Both are Nevada corporations based in Boca Raton, Florida, according to the complaint. The complaint says Celsius has the No. 2 energy drink portfolio in the United States with about a 20% share, citing the company's own figures, and that its sales grew from $300 million in 2021 to $2.5 billion in 2025. Courthouse News reported that Celsius also owns Rockstar Energy.

These are allegations The complaint is the plaintiff's account of the facts and her legal theories. Celsius has not responded in court, and no judge has decided whether the labels are misleading.

The products named in the complaint

The complaint lists 19 products it calls the "Healthwashed Energy Products." They include:

• Essential Energy Sparkling: Galaxy Vibe, Astro Vibe, Arctic Vibe, Tropical Vibe, Peach Vibe, Raspberry Peach, Wild Berry, Watermelon, Grape Rush, Orange, Strawberry Lemonade, Fuji Apple Pear and Kiwi Strawberry.
• Fizz Free and related flavors: Pink Lemonade, Blue Razz Lemonade and Raspberry Acai Green Tea.
• On-the-Go: Strawberry Coconut, Blueberry Lemonade and Cranberry Lemon.

The complaint also argues shoppers pay a premium for the claims. It lists several 12-ounce Celsius drinks at $0.21 per ounce and compares them with other energy drinks it priced between $0.15 and $0.21 per ounce, including products from Monster, Ghost, C4 and Starbucks. The complaint does not say where or when those prices were collected.

The science dispute

Celsius's marketing points to research. The complaint quotes the company's website as saying the drinks are "clinically proven to accelerate your metabolism," that "all of the studies show that CELSIUS has thermogenic properties," and that drinking one before exercise "can help reduce body fat." Thermogenesis means the body producing heat, which burns calories. The complaint acknowledges that the drinks contain ingredients with real thermogenic properties, but it says the evidence supports only small, temporary increases in metabolism and fat burning.

The plaintiff does not dispute that some ingredients have thermogenic effects. Her argument is about what the studies show and who paid for them. The complaint alleges:

• Funding. All six studies Celsius cites were "solicited and funded by Celsius itself."
• Authors. All but one of the studies share common authors, and the sixth was conducted by "a now long-defunct business entity."
• What was measured. The studies looked at short-term markers such as resting energy expenditure and free fatty acid levels "over a matter of hours, not fat loss over weeks."

The complaint also cites independent research. It points to a 2012 Cochrane review of green tea studies that found weight loss in adults taking green tea preparations was "statistically not significant, was very small and is not likely to be clinically important." It also cites a 2024 meta-analysis that concluded adding green tea to exercise training "has no additional effect on lipid profile."

A temporary boost is not the same as fat loss The plaintiff's central argument is that raising metabolic rate for a few hours does not prove a drink makes people leaner. Celsius has not yet responded to that argument in court, and the court has not weighed the evidence.

The complaint also quotes Celsius executives. It cites CEO John Fieldly describing the brand as delivering "clinically proven fat-burning and metabolism acceleration," and Chief Marketing Officer Kyle Watson saying the brand launched as a "zero calorie fat burning drink" before shifting toward a "live fit" lifestyle position. The plaintiff uses these statements to argue that the fitness and fat-burning message is central to how Celsius sells its drinks.

What healthwashing means

The complaint describes the case as one about "healthwashing." It defines the term as advertising a product with inappropriate or misleading health claims, often by linking it to a healthy lifestyle such as fitness or sports. The complaint says Celsius engaged in the "improves function" type, which describes how a product is supposed to affect the body's normal functions.

The term is not a legal standard. Whether the labels are unlawful will depend on Washington consumer protection law and on what a reasonable consumer would understand from them.

The legal claims

The complaint has two counts.

• Washington Consumer Protection Act. The state law, RCW 19.86, prohibits unfair or deceptive acts in trade or commerce. The plaintiff argues the front labels are deceptive and caused her and other buyers financial harm.
• Fraudulent concealment. The plaintiff claims Celsius knew the studies were limited and failed to disclose that to shoppers.

The complaint asks the court to certify a class, stop the challenged marketing, and award restitution, damages including punitive damages, disgorgement of profits, interest, costs and attorneys' fees. It also demands a jury trial. It argues the deadline to sue should be extended because buyers could not have discovered the problem on their own.

Nielsen is represented by Hagens Berman Sobol Shapiro, including Steve W. Berman, and by Wexler Boley & Elgersma.

Timeline

Who may be affected and what you can do now

The proposed class covers people who bought one of the listed products in Washington from October 26, 2022, through the time of trial. Buyers in other states are not covered by this complaint as filed, and the complaint excludes Celsius and certain related parties.

There is nothing to sign up for. If a class is certified or the case settles, notice would explain who qualifies and how to claim. Proof of purchase can help in consumer settlements, so keeping receipts or online order histories may be useful, although many food and drink settlements also accept claims without receipts up to a limit.

No refund program exists yet Be cautious of any website or message asking for a fee or bank details to get a "Celsius refund." Any legitimate settlement would be approved by a court and announced by a settlement administrator.

You can also browse our list of class action cases you can join to see open claims.

What remains unresolved

• Celsius's response. The company has not filed an answer or motion in court.
• The studies themselves. The court has not reviewed the six studies Celsius cites or decided how much weight they deserve.
• The back-label disclaimer. Whether the small print limits the front claims enough is a central open question.
• Other states. We have not confirmed whether similar suits have been filed elsewhere.

This article is for information only and is not legal advice. The allegations have not been proven.

What happens next

Celsius will respond to the complaint, either by answering it or by asking the judge to dismiss the claims. Food and drink labeling cases are often decided early on whether a reasonable consumer could be misled. If the case survives, it would move into discovery. We will update this story as the case develops.

Frequently asked questions

What is the Celsius energy drink lawsuit about?

A Washington buyer alleges Celsius labels saying "Accelerates Metabolism" and "Burns Body Fat" mislead consumers because the supporting studies were company-funded and measured only short-term effects.

Which Celsius products are included?

The complaint lists 19 products, including many Essential Energy Sparkling flavors, Fizz Free Pink Lemonade and three On-the-Go flavors.

Can I get money from the Celsius lawsuit?

Not yet. There is no settlement or claim form. Any payment would depend on a court ruling or a settlement approved by the judge.

Who is covered by the proposed class?

People who bought a listed product in Washington from October 26, 2022, through trial. A judge must certify the class first.

Does Celsius admit the claims are false?

No. Celsius has not responded in court, and it did not immediately comment to Courthouse News.

Is Celsius unsafe to drink?

The lawsuit does not claim the drinks are unsafe. It challenges marketing claims about metabolism and fat burning.