The Rise of Big Food Litigation: Is a Landmark Decision in Pennsylvania Only the Beginning?

Anand Agneshwar & Jocelyn Wiesner*

For decades, the plaintiffs’ bar rode the wave of “Big Tobacco” litigation, bringing lawsuits across the country that allege deliberate concealment of the addictive nature of nicotine and the health consequences of tobacco. That playbook is now being imported into novel litigation against the food and beverage industry. The ultra-processed food (UPF) litigation landscape is young, but it is moving fast. A landmark ruling from the Eastern District of Pennsylvania in August 2025 in a personal injury case provides the first meaningful judicial signpost for how these cases will be evaluated — and offers important lessons for defendants and their counsel. At the same time, new complaints by the City of San Francisco and additional personal injury plaintiffs, coupled with accelerating regulatory activity, make clear that the Pennsylvania dismissal is a pause, not an end.

I. What Are Ultra-Processed Foods—and Why Does the Definition Matter?

There is a threshold question that requires attention: What constitutes ultra-processed foods? Currently, there is no universally accepted scientific or legal definition of “ultra-processed food.” This definitional ambiguity is more than a technicality—it sits at the heart of both the litigation and the regulatory landscape, and will shape what legal theories and defenses are available to both plaintiffs and defendants.

Thus far, plaintiffs have relied on the NOVA classification system, a framework that categorizes foods based on degree of processing rather than nutritional content. Under NOVA, “ultra-processed foods” are described as “industrial formulations made entirely or mostly from substances extracted from foods . . . derived from food constituents . . . or synthesized in laboratories from food substrates.” Common examples include soft drinks, packaged snacks, frozen meals, breakfast cereals, processed meats, and candy.

The NOVA definition is broad, however, and has the potential to sweep in foods with documented health benefits, such as certain whole grain products, yogurts, plant-based proteins, and even infant formula. FDA, for its part, is seeking to establish a uniform definition—which was expanded to come as early as April 2026. In July 2025, FDA, HHS, and USDA jointly published a Request for Information seeking public input to develop a uniform federal definition of UPFs—the first such effort in agency history.[1] As discussed further below, the outcome of that process could have significant implications for UPF litigation going forward.

II. Martinez v. Kraft Heinz: The Test Case and Its Lessons

Background

Martinez v. Kraft Heinz Company[2] is widely regarded as the opening salvo in what may become large-scale UPF mass tort litigation. The case, originally filed in Philadelphia County on December 10, 2024, and subsequently removed to the Eastern District of Pennsylvania, names eleven of the largest food and beverage companies in the country: Kraft Heinz Company, Inc., Coca-Cola, PepsiCo Inc., General Mills, Inc., Nestlé USA Inc., WK Kellogg Co., Mars Incorporated, Inc., Mondelez International, Inc., Post Holdings, Inc., ConAgra Brands, Inc., and Kellanova.

Plaintiff Bryce Martinez, a Pennsylvania teenager, alleged that his regular consumption of unspecified UPFs throughout his adolescence caused him to develop type 2 diabetes and non-alcoholic fatty liver disease at age sixteen—conditions the complaint characterized as historically confined to older adults. The 147-page, 668-paragraph complaint explicitly invoked the tobacco litigation framework, alleging that “Big Tobacco took over the American food environment” in the 1980s.[3] The complaint further argued that tobacco companies deliberately transplanted their “addiction science” and marketing techniques directly into the food industry through a series of acquisitions and mergers with food companies. The complaint asserted a wide array of state law claims, including negligence, failure to warn, breach of implied warranty, fraudulent misrepresentation and concealment, and concerted action.

Notwithstanding the length, the complaint was relatively bereft of relevant details. Although it alleged that over 100 brands encompassing thousands of products contained UPFs, it failed to allege which specific products plaintiff consumed. Further, the complaint relied on general studies suggesting an association between UPFs and various health consequences without identifying a link between any specific UPF he consumed and his alleged injuries. This approach reflects a fundamental weakness in UPF personal injury claims: even strong population-level epidemiological studies do not establish specific causation for an individual plaintiff.

The Court’s Decision

On August 25, 2025, Judge Mia Roberts Perez dismissed the complaint in its entirety, finding it “woefully deficient” on two independent grounds: failure to plausibly allege specific causation, and failure to provide sufficient notice to defendants under Federal Rule of Civil Procedure 8.

A plaintiff asserting a products liability claim must plausibly allege both general causation (that the substance is capable of causing the observed harm) and specific causation (that it actually caused the plaintiff’s harm). Focusing on specific causation, the court heavily criticized the lengthy complaint for containing only nine specific allegations about the plaintiff: the “most substantive of which being that Plaintiff regularly ingested UPFs and was diagnosed with type 2 diabetes and non-alcoholic liver disease at the age of 16.”[4] The complaint contained no allegations regarding how often he consumed defendants’ products, in what quantities, over what time period, or how those consumption patterns related to the onset of his conditions. Because the plaintiff had failed to “plead more than a mere possibility of causation,” it did not pass muster under Rule 8.[5]

Although the court did not rule on general causation, it clearly recognized the hurdles plaintiff would face given the “reality that these diseases have a multitude of causes.”[6] As the court emphasized, type 2 diabetes and non-alcoholic fatty liver disease have numerous potential causes—including genetics, sedentary lifestyle, and diet generally—and attributing these conditions to specific defendants’ products without particularized factual allegations was implausible under Twombly.

The court also found that the complaint independently failed Rule 8’s notice requirement. The complaint named eleven defendants and pointed to more than 100 brands, placing thousands of products at issue, without attributing particular conduct or specific products to particular defendants. Such shotgun pleading makes it “impossible for each Defendant to determine what conduct, design, promotion, sale, or product Plaintiff is referring to.”[7]

Notwithstanding the pleading deficiencies, Judge Perez expressed sympathy for the public health concerns underlying the litigation, noting that the court was “deeply concerned about the practices used to create and market UPFs, and the deleterious effect UPFs have on children and the American diet.”[8]

Nor did she address the defendants’ remaining legal arguments, including whether the complaint compelled unsupported scientific speech in violation of the First Amendment, or whether the claims were preempted by federal food labeling laws. Nonetheless, the court’s heavy criticism of the complaint reflects a practical reality that personal injury plaintiffs will face significant challenges in pleading—and ultimately proving—causation.

The plaintiff subsequently filed a motion for leave to amend in late November 2025, which remains pending as of the date of this article. That proposed complaint, however, continues to suffer from significant deficiencies. For example, it relies on general literature linking UPFs generally to certain diseases without discussing any particular product, and fails to meaningfully contend with the allegation that plaintiff consumed UPFs from 180 different products (let alone the multitude of other environmental factors at play).

III. UPF Litigation Across the Country

Martinez was only the first salvo in the UPF litigation. In the first three months of 2026, the same firms in Martinez have filed copycat complaints across the country alleging harm from consumption of UPFs—signaling their intent to seek an MDL.[9] These personal injury cases target the same group of defendants and utilize the same tobacco-framework set forth in Martinez. And importantly, plaintiffs are learning: While they draw directly on the original Martinez narrative framework, they have mirrored the more detailed (albeit likely still deficient) product-specific, defendant-specific consumption allegations found in the proposed amended Martinez complaint in a clear attempt to overcome a motion to dismiss.

Take Lawton v. Kraft Heinz Co.[10] for example. Much like in Martinez, the plaintiff alleges that he regularly consumed UPFs, which led to his diagnosis of type 2 diabetes at age nine. And as with the proposed amended Martinez complaint, the plaintiff alleges which specific products he consumed and at what regularity. For example, the complaint alleges that the plaintiff regularly consumed Capri Sun approximately three times per week, Cool Whip approximately three times per month, Jell-O Pudding approximately three times per week, Velveeta approximately three times per year, and Stove Top approximately four times per year.

The complaint further alleges that plaintiff’s long-term, chronic, and regular exposure to these specific products—beginning as early as 2011 and continuing until his 2019 diagnosis—caused chronic metabolic dysfunction, a chronic inflammatory state, and increased insulin resistance that substantially contributed to his type 2 diabetes. The complaint alleges there are “no plausible alternative explanations” for J.L.’s injuries, and expressly argues that, had he not regularly consumed UPFs manufactured by the defendants over many years, he would not have been diagnosed at age nine.

This level of product-level specificity now appearing in UPF complaints is likely a direct and deliberate response to the fatal defect Judge Perez identified in Martinez. Whether it is sufficient is yet to be seen as these cases are still in their infancy: In both Lawton v. Kraft Heinz and Muthusami v. Kraft Heinz, courts adopted coordinated briefing schedules permitting defendants to file omnibus motions to dismiss, but to date no motions have been ruled on.[11]

IV. People v. Kraft Heinz: The Government Action in California

On December 2, 2025, San Francisco City Attorney David Chiu filed suit in San Francisco Superior Court against the same eleven food manufacturers. The case—People v. Kraft Heinz Co.—was filed on behalf of the People of the State of California and subsequently removed to the Northern District of California in January 2026.[12] On April 23, 2026, Judge Jon Tigar granted the City’s motion to remand, returning the case to San Francisco Superior Court.

The same law firm that filed the Martinez case—Morgan & Morgan—are co-counsel, signaling a coordinated litigation campaign across multiple fronts.

The California complaint, which seeks both injunctive relief and civil penalties, asserts violations of California’s Unfair Competition Law, Business & Professions Code § 17,200, and the state’s public nuisance statute. As with the personal injury cases, the complaint draws analogies to tobacco litigation, alleging that defendants followed the “Big Tobacco Playbook,” engaging in deliberate actions to make UPFs addictive and target vulnerable populations.

Government actions like this are perhaps more dangerous than personal injury cases—though not immune from significant challenges. Unlike in personal injury cases, government plaintiffs acting under consumer protection or public nuisance theories generally need to demonstrate only general causation—that defendants’ conduct was capable of contributing to public harm. They generally do not have to prove that any particular consumer was deceived or suffered actual harm; only whether the deception is material and would deceive a reasonable consumer. This eliminates the central vulnerability that doomed the original Martinez complaint.

Moreover, government actors asserting consumer protection civil penalties do so in the hopes of obtaining huge awards: Such plaintiffs often allege that each individual purchase is its own penalty, each subject to a statutory penalty of thousands of dollars.

That said, government cases like this are not without burden. As with personal injury cases, government actors will have to contend with the amorphous nature of UPFs and the relative scientific uncertainty. Such claims will likewise face federal preemption headwinds as well as strong First Amendment arguments against any theory that would compel disclosure of nutritional characterizations.

V. The Regulatory Landscape: Why Definition Will Define the Litigation

The UPF litigation is unfolding against a backdrop of evolving regulatory action. Both FDA Commissioner Marty Makary and HHS Secretary Robert F. Kennedy Jr. have raised concerns about the potential link between UPFs and chronic diseases. FDA, for example, stated that the United States “faces a growing epidemic of preventable diet-related chronic diseases” and that researchers “have found links between the consumption of [UPFs] and a range of negative health outcomes.”[13]

On July 25, 2025, FDA, HHS, and USDA jointly published a Request for Information (RFI) seeking public input on a uniform definition of ultra-processed foods.[14] The RFI explicitly acknowledged that “there is no single, universally accepted definition of UPFs” and that classification systems vary significantly. Although no definition has come out of that process yet, the comment period closed in October 2025 and Kennedy had previously indicated that a definition would be issued in April 2026 with “front-of package food labeling” to follow.[15]

The RFI process bears close monitoring. The definitional question that was central to defendants’ motion to dismiss in Martinez will eventually have a federal answer, and that answer could reshape the litigation landscape in critical ways. For example, a formal definition could act as a bright line standard for litigation defining which specific products are (and are not) subject to potential liability. Conversely, to the extent FDA steps in to regulate UPFs and the corresponding product labels, doing so could serve as a preemption shield against state tort claims requiring additional or different disclosures or designs.

The Impact

Despite the speed and coordination with which the UPF litigation wave is building, defendants have substantial grounds to defeat it—both in individual personal injury actions and in the more formidable government cases.

On the personal injury side, causation is not merely a pleading problem. The prevailing scientific literature on UPFs, while generating epidemiological associations at a population-level, do not establish causation at the individual level. As the court in Martinez recognized in granting dismissal of the original complaint, the alleged “diseases have a multitude of causes” and confounding factors,[16] including genetics, socioeconomic status, overall dietary patterns, physical activity, and other lifestyle factors. Even if a plaintiff could surpass that hurdle, given the prevalence of UPF as currently defined, it will be difficult if not impossible for plaintiffs to link an injury to any particular defendant. Plaintiffs who consume a dozen different defendants’ products daily cannot reliably attribute a complex, multifactorial metabolic condition to any one product, any one defendant, or even UPF consumption as a whole. Individually tried, these cases are unlikely to withstand summary judgment on causation in any jurisdiction that applies a rigorous Daubert standard to expert testimony on specific causation.

The prospects for aggregation through multidistrict litigation (MDL) or class action do not materially improve plaintiffs’ position, and may in fact sharpen the defense. Although there is no MDL yet, it would appear that the plaintiffs’ bar is positioning itself for one by filing cases across the country. If the plaintiffs’ bar is successful in consolidating these cases, defendants should vigorously push for a schedule that requires early resolution of the key causation questions.

On the class action front, a putative class of UPF consumers—alleging personal injury or consumer fraud—would face nearly insuperable obstacles under Rule 23(b)(3). The causation inquiry in any individual UPF injury case is inherently plaintiff-specific: which advertisements was plaintiff exposed to, which products did this person consume, in what quantities, over what period, against what genetic and lifestyle background, to name just a few. Such questions cannot be resolved on a class-wide basis.

Government cases present a more serious challenge—but not an insurmountable one. Although these consumer protection plaintiffs need not prove individual reliance or specific causation for each affected consumer, they will face significant scientific hurdles as with personal injury cases.

Taken together, these defenses—causation science, class certification obstacles, federal preemption, and First Amendment protection—provide a robust architecture for contesting UPF litigation at every stage, and defendants and their counsel should be developing each of them in parallel.

Conclusion

The UPF litigation wave is not a hypothetical. The Martinez dismissal provides a real-time demonstration of the pleading standards plaintiffs must meet and the arguments defendants have available. But additional complaints, filed just months later and directly designed to correct the deficiencies of the original complaint in Martinez, show that plaintiffs’ counsel are reacting quickly—and in a coordinated fashion. The City of San Francisco action, meanwhile, presents a fundamentally different legal threat that the Martinez dismissal does not address.

The dismissal is no doubt correct, but is not the end of the story. Companies should closely track developments across the cases and whether they survive early motions to dismiss or jurisdictional challenges.

        Note: As of the date of publication, the plaintiff in Martinez v. Kraft Heinz has filed a motion for leave to amend his complaint, which remains pending before Judge Perez in the Eastern District of Pennsylvania. The San Francisco action, People v. Kraft Heinz, was remanded on April 23, 2026, but is still at its earliest procedural stages. A case management conference is currently set for July 1, 2026. Lawton v. Kraft Heinz was filed on February 12, 2026 in the Southern District of Mississippi. Defendants filed a motion to dismiss as well as a motion to stay proceedings pending resolution of the MTD on May 1; both motions remain pending.

 

* Anand Agneshwar co-chairs Arnold & Porter’s Product Liability Litigation practice group. He represents pharmaceutical and consumer product companies as national, strategic, trial, and appellate counsel in product liability and related litigation. Jocelyn Wiesner is Counsel in Arnold & Porter’s Product Liability Litigation practice group. She has extensive experience litigating pharmaceutical and medical device product liability actions, as well as consumer protection actions brought by state attorneys general.

[1]   90 Fed. Reg. 35,305 (July 25, 2025).

[2]   No. 2:25-cv-00377 (E.D. Pa.).

[3]   Compl. at 7.

[4]   Op. at 1.

[5]   Id. at 4.

[6]   Op. at 4.

[7]   Op. at 6.

[8]   Op. at 2.

[9]   See, e.g., Lawton v. Kraft Heinz Co., No. 1:26-cv-44 (S.D. Miss.); Ford v. Kraft Heinz Co., No. 3:26-cv-00077 (E.D. Ark. Mar. 5, 2026); Jenkins v. Kraft Heinz Co., No. 2:26-cv-00115 (E.D. La.) (voluntarily dismissed without prejudice on March 30, 2026); Muthusami v. Kraft Heinz Co., No. 6:26-cv-00113 (M.D. Fla.); Sanford v. Kraft Heinz Co., No. 7:26-cv-01430 (S.D.N.Y.).

[10] No. 1:26-cv-44 (S.D. Miss.).

[11] Defendants filed a motion to dismiss in Lawton on May 1. The court set the deadline to file a motion in Muthusami for June 17, 2026. Those motions may provide the next meaningful judicial guidance regarding whether plaintiffs’ more product-specific allegations are sufficient to overcome the causation and notice deficiencies identified in Martinez.

[12] People v. Kraft Heinz Co., No. 4:26-v-00183 (N.D. Cal.).

[13] See Ultra-Processed Foods, U.S. Food & Drug Admin. (Sept. 18, 2025), https://www.fda.gov/food/nutrition-food-labeling-and-critical-foods/ultra-processed-foods.

[14] Docket No. FDA-2025-N-1793; 90 Fed. Reg. 35,305.

[15] Notably, some states have begun moving ahead of federal regulators. California enacted legislation in October 2025 establishing a statutory definition of certain “ultra-processed foods of concern” in the school-food context, creating one of the first state-law frameworks directed specifically at UPFs. While the statute is limited in scope, plaintiffs and regulators may seek to invoke such state-level definitions in future litigation as evidence of emerging regulatory consensus.

[16] Op. at 4.