What counts as a structure/function claim

Under Section 403(r)(6) of the Federal Food, Drug, and Cosmetic Act, a structure/function claim is a statement that "describes the role of a nutrient or dietary ingredient intended to affect the structure or function in humans," or that "characterizes the documented mechanism by which a nutrient or dietary ingredient acts to maintain such structure or function." Classic examples include "calcium builds strong bones" and "fiber maintains bowel regularity" (FDA).

The same notification requirement also covers two related claim types: general well-being claims (statements describing general well-being from consuming a nutrient or ingredient) and classical nutrient deficiency disease claims (a statement about a benefit related to a recognized nutrient deficiency disease, paired with a disclosure of that disease's prevalence in the US).

This is a dietary-supplement-specific obligation. Conventional food manufacturers can make structure/function claims without notifying FDA at all — the notification and disclaimer requirements exist because DSHEA (the Dietary Supplement Health and Education Act of 1994) created special rules specifically for supplements.

The required disclaimer

Any structure/function, general well-being, or nutrient deficiency claim on a supplement label must be accompanied by this exact standard disclaimer, prominently displayed in boldface type:

Required label language

"This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease."

The claim also can't cross the line into diagnosing, mitigating, treating, curing, or preventing a specific disease — the moment it does, it becomes a disease claim (which requires drug-level approval, not a supplement notification) rather than a structure/function claim (FDA).

The 30-day FDA notification rule

Before you can rely on a structure/function claim, two things have to be true: you need substantiation that the statement is truthful and not misleading, and you need to submit a notification to FDA with the text of the claim no later than 30 days after first marketing the product with that claim. This is a notification, not a pre-approval — FDA doesn't review and approve the claim in advance, but the notification has to be filed on time regardless.

FDA's preferred channel is the electronic Centralized Online Submission Module (COSM), which replaced the older FURLS system in 2019. Written/paper submissions are still accepted but are the slower path. Submissions can also be reused: the same COSM account carries forward for future notifications, and you can list multiple brand variations, package sizes, or flavors of the same formula under a single notification rather than filing separately for each SKU variant.

What has to be in the notification

A complete Section 403(r)(6) notification requires:

Notifications that get a response are posted publicly on regulations.gov, typically 60-90 days after processing — so a competitor's structure/function claims (and the courtesy letters FDA sends about them) are a matter of public record you can look up before launching a similar claim yourself (FDA).

What "substantiation" actually means to the FTC

Filing the FDA notification is a labeling formality — it is not proof your claim is defensible. That burden sits with the FTC's advertising substantiation standard, which the agency has distilled to two principles: advertising must be truthful and not misleading, and before running an ad, you must already have adequate substantiation for every objective claim it makes, express or implied (FTC Health Products Compliance Guidance).

The FTC evaluates substantiation on a sliding scale, not a checklist. Its published factors include:

FactorWhat it means in practice
Amount and type of evidenceMore specific, quantified claims ("reduces X by 30%") need stronger evidence than general ones
Quality of the evidenceRandomized, controlled, human clinical trials carry far more weight than in vitro, animal, or anecdotal data
Totality of the evidenceFTC weighs the full body of research, not just the studies favorable to the claim
Relevance to the specific claimA study has to test the actual product, dose, and population the claim is made about — not a related ingredient or a different formulation

One detail that catches brands off guard: referencing DSHEA notification procedures in your marketing can itself become a violation. FTC guidance flags language implying that FDA "has authorized" or "reviewed and found effective" a claim because of a notification filing — that's misleading, since the notification process doesn't involve FDA evaluating or approving the claim's substance.

Common mistakes that draw scrutiny

Pre-launch checklist

Track every claim against its evidence — in one place.

The Claims Substantiation Tracker is a 23-column workbook plus a 7-page practitioner's guide for logging every marketing and structure/function claim alongside the clinical support behind it, graded against the FTC's evidence hierarchy and FDA's 403(r)(6) rules.

See the tracker — $29

This guide is educational and reflects FDA and FTC published guidance as of July 2026. It is not legal or regulatory advice, and does not replace review by qualified regulatory counsel for your specific products and claims.