Structure/Function Claims Under DSHEA:
What’s Allowed, What’s Not, and Why It Matters
Structure/function claims are among the most misunderstood areas of dietary supplement regulation. Many companies believe that avoiding disease claims automatically makes their marketing compliant. In reality, the scientific evidence behind the claim — not simply the wording — often determines whether that claim can withstand regulatory scrutiny. The risk is not hypothetical: it appears in FDA warning letters, FTC enforcement actions, retailer compliance holds, and class-action litigation.
← Back to InsightsStructure/function claims describe how a nutrient or ingredient affects normal body structure or function, and DSHEA permits their use without pre-market FDA approval — but not without competent and reliable scientific evidence. Misunderstanding this distinction is one of the most common and costly regulatory mistakes supplement companies make. Before any claim appears on a label or in marketing, brands should verify that the supporting evidence is product-specific, well-documented, and scientifically defensible.
Here’s the Problem
The Dietary Supplement Health and Education Act of 1994 — DSHEA — created a regulatory framework that permits supplement companies to make structure/function claims without seeking FDA pre-approval. This is genuinely significant commercial freedom. It is also widely misread as freedom from scientific obligation. It is not.
A structure/function claim describes how an ingredient affects the normal structure or function of the body. “Supports immune health,” “promotes digestive balance,” and “helps maintain healthy joints” are all structure/function claims. They are permitted under DSHEA, but only when supported by competent and reliable scientific evidence — a standard that the FDA, the FTC, and increasingly, retail partners and opposing litigation experts apply with real scrutiny.
The common error is not using a prohibited claim type. It is using a permissible claim type with insufficient or mismatched evidence. A company may craft wording that avoids disease language entirely and still face serious regulatory exposure because the science behind the claim does not hold up.
Why It Matters
The consequences of weak or mismatched substantiation extend well beyond regulatory compliance:
- FDA warning letters can require immediate label changes, product recall, or public disclosure
- FTC enforcement targets advertising and digital marketing — not just labels — applying the same substantiation standard
- Major retail partners conduct independent scientific reviews before accepting supplement products
- Amazon has its own compliance processes that can result in listing suppression or removal
- Class-action litigation routinely challenges supplement claims where substantiation is weak or generic
- Investor and acquirer due diligence consistently surfaces unsubstantiated or poorly documented claims
- Reputational damage from public enforcement or litigation is difficult to reverse
Each of these risks is substantially reduced when substantiation is built correctly before launch — and substantially increased when it is assembled reactively under pressure.
“Two claims can use identical wording and carry dramatically different levels of regulatory risk — because the science behind them is entirely different.”
A Real Example: Same Words, Different Risk
Two supplement products both carry the claim “supports immune health.” The wording is identical. The regulatory exposure is not.
The first product contains an ingredient with multiple well-designed human clinical trials demonstrating immune-related outcomes at the dose used in the formulation. The second cites studies conducted on a different ingredient, at a higher dose, in a clinical population rather than healthy adults. Both products use a compliant claim structure. Only one has defensible substantiation. The distinction — invisible from the label — is what determines regulatory and litigation risk in the event of scrutiny.
Wording alone does not determine compliance. Evidence must match the ingredient, the dose, the delivery format, and the intended consumer population. Generic category evidence — studies that support the ingredient class rather than the specific ingredient in the product — is one of the most common and most vulnerable forms of substantiation.
What Regulators Actually Look For
Whether it is an FDA review, an FTC inquiry, a retailer compliance assessment, or opposing expert analysis in litigation, the scrutiny follows the same logic:
| Question | Why it matters |
|---|---|
| Is the wording a structure/function claim? | Disease claims are prohibited under DSHEA — structure/function claims are permitted but require notification and substantiation |
| What scientific evidence supports it? | Competent and reliable evidence requires well-designed studies — anecdotal, in vitro, or animal data alone is generally insufficient |
| Does the evidence match the ingredient? | Evidence generated for a different ingredient — even a closely related one — does not substantiate a claim for the ingredient actually in the product |
| Does the evidence match the dose? | A study demonstrating an effect at 1,000 mg does not substantiate a claim for a product delivering 250 mg |
| Does the evidence match the intended population? | Clinical trial data from patient populations may not transfer to healthy adult consumers making everyday purchasing decisions |
| Is the claim proportionate to the evidence? | Overstating what a study demonstrates is an independent evidentiary failure — one that opposing experts are specifically trained to identify |
What to Do
- Clearly define every intended claim before it appears on any label, website, retailer page, or marketing asset
- Map each claim to product-specific scientific evidence — not category evidence or borrowed studies from related ingredients
- Verify that the ingredient identity, dose, delivery format, and intended population in the supporting studies match the actual product
- Identify evidentiary gaps before launch, not after a warning letter or retailer compliance hold forces a response
- Build and maintain a documented substantiation file that can be produced quickly in the event of regulatory, retailer, or legal scrutiny
- Review claims periodically as the scientific evidence base evolves and as the product formulation or positioning changes
The supplement companies that navigate the regulatory environment most successfully treat scientific substantiation as a business strategy — not a compliance checkbox. Strong evidence, properly documented and matched to the specific product, is a commercial asset that protects market access, retailer relationships, and brand credibility over time.
- Dietary Supplement Health and Education Act of 1994 (DSHEA). Pub. L. No. 103-417, 108 Stat. 4325.
- U.S. Food & Drug Administration. Guidance for Industry: Substantiation for Dietary Supplement Claims Made Under Section 403(r)(6) of the Federal Food, Drug, and Cosmetic Act. FDA, 2008.
- U.S. Food & Drug Administration. Dietary Supplements: Structure/Function Claims. FDA, 2023.
- Federal Trade Commission. Health Products Compliance Guidance. FTC, 2022.
Five things this article establishes
- 1 Structure/function claims do not require FDA pre-approval under DSHEA — but they still require competent and reliable scientific evidence to be legally defensible.
- 2 Claim wording alone does not determine compliance; the quality and specificity of the supporting evidence is what distinguishes a defensible claim from a vulnerable one.
- 3 Product-specific evidence — matched to the actual ingredient, dose, delivery format, and consumer population — is far stronger than generic category evidence.
- 4 Weak substantiation increases exposure to FDA warning letters, FTC enforcement, retailer delisting, class-action litigation, and investor due diligence findings.
- 5 Building a documented substantiation file before launch is significantly less costly than assembling one reactively after regulatory, retailer, or legal scrutiny arrives.
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