March 30, 2026

When Science Moves Faster Than FDA Labeling Rules: Litigation Risk Intensifies

4 min

A Methodology Dispute Disguised as a Labeling Case

The gap between FDA's labeling rules and modern nutrition science is no longer theoretical-it is becoming a focal point for litigation. A recently filed class action against David Protein illustrates this trend, alleging that protein bars labeled as containing 150 calories actually contain significantly more-reportedly between 263 and 275 calories-with fat levels also exceeding declared values. But beyond the headline allegations, the case turns on a more fundamental question: how calories should be calculated in the first place.

At the center of the dispute is a methodological divide. Plaintiffs rely on traditional approaches, including Atwater factors and AOAC analytical protocols, while the company points to the metabolic behavior of esterified propoxylated glycerol (EPG), a fat substitute that is largely undigested and therefore contributes fewer metabolically available calories. FDA regulations under 21 C.F.R. Section 101.9 contemplate ingredient-specific caloric values in certain circumstances, placing this dispute squarely within a regulatory, not purely factual, framework. The distinction between gross caloric content and metabolically available energy is where the legal risk increasingly sits.

Regulatory Flexibility Is Not a Safe Harbor

This case reflects a broader reality: companies may face litigation exposure even where they rely on scientifically supportable and FDA-recognized methodologies. A key source of confusion and risk is the distinction between declaration tolerances and methodological choice. FDA's tolerance provisions allow for limited variation between declared and actual nutrient values to account for manufacturing and testing variability, functioning as a post-declaration compliance standard. By contrast, methodological choice refers to the selection of an FDA-permitted approach to calculating nutrient content-such as Atwater factors, bomb calorimetry, or ingredient-specific values-and is a pre-declaration decision.

In practice, these concepts are often conflated. Here, reliance on an ingredient-specific caloric value appears to produce a materially lower declared value than traditional methods would suggest. Whether that approach is sufficiently supported and documented is precisely the type of issue now being tested in litigation. Importantly, neither tolerances nor methodological flexibility operate as safe harbors. They are intended to address scientific uncertainty, not to enable systematic optimization of label declarations. Patterns that appear outcome-driven-such as repeated reliance on methodologies that consistently produce lower declared values-are likely to draw scrutiny from plaintiffs, FDA, and the FTC.

Expanding Risk for Nutrient Content Claims

Litigation risk is also expanding beyond how nutrients are measured to how they are described. Plaintiffs are increasingly targeting alleged violations of FDA's nutrient content claim regulations, including statements regarding calories, fat, and added sugars, as well as "free," "low," and "no added" claims. A key takeaway is that a statement may be factually accurate but still actionable if it does not satisfy FDA's regulatory conditions for use.

For example, "no added sugars" claims may be used only where specified criteria are met and may be prohibited where products exceed disqualifying nutrient thresholds. This issue is particularly acute in the infant and toddler nutrition category, where FDA has taken the position that such claims may be inherently misleading, even as emerging research suggests early exposure to added sugars may have long-term metabolic effects. This tension reflects a broader dynamic: in some contexts, the regulatory framework may limit communication of information aligned with current science.

Litigation as a Substitute for Regulatory Clarity

These cases increasingly place courts in the position of resolving disputes grounded in scientific and regulatory judgment, including competing methodologies and the metabolic impact of novel ingredients. Plaintiffs' firms are leveraging state consumer protection laws and FDA standards to bring claims that function, in effect, as private enforcement of labeling requirements, particularly where agency guidance has not kept pace with innovation.

Defendants retain important tools, including preemption under the Nutrition Labeling and Education Act (NLEA) and the primary jurisdiction doctrine, under which courts may defer to FDA on technical issues. While not dispositive, these defenses remain central to litigation strategy.

What This Means for Industry

The David Protein litigation reflects a broader shift in labeling risk. Exposure is no longer limited to whether a statement is accurate but increasingly turns on whether it fits within FDA's regulatory framework and whether the underlying methodology can be defended as reasonable, consistent, and well supported. As nutrition science continues to evolve more rapidly than FDA guidance, that gap is likely to widen, and the associated litigation risk is likely to increase.

In this environment, companies should take a disciplined approach to labeling and claims substantiation. In particular:

  • Document methodological decisions to ensure nutrient calculations are supported, consistent, and defensible
  • Stress-test label outcomes under traditional and alternative analytical frameworks
  • Reevaluate claims strategy, including "absence" claims such as "no added sugars," for compliance with FDA authorization requirements
  • Focus on higher-risk categories, including novel ingredients, reduced-calorie formulations, and products intended for infants and young children

Scientific accuracy remains necessary. It is no longer sufficient.

Venable's Food and Drug Law team is tracking the issue closely and can provide you with updates. Please contact the authors with any questions.