If you sell dietary supplements, structure/function claims are the main kind of benefit statement open to you without FDA approval. The line between one of these and a disease claim is narrow, and it runs through ordinary product copy. This guide explains the definition, the conditions and some examples. This is general information, not legal advice.
What a structure/function claim is
According to the FDA, a structure/function claim describes the role of a nutrient or dietary ingredient intended to affect the normal structure or function of the human body. It can also describe how the ingredient acts to maintain that structure or function.
The FDA gives these examples:
- ✅ "Calcium builds strong bones"
- ✅ "Fiber maintains bowel regularity"
- ✅ "Antioxidants maintain cell integrity"
Each one names a normal body function. None of them names a disease.
Where it becomes a disease claim
The FDA says only a drug can legally make a disease claim. A supplement that claims to diagnose, treat, cure or prevent a disease has crossed the line, whatever the rest of the page says. The regulation that separates the two is 21 CFR 101.93.
| Structure/function claim | Disease claim |
|---|---|
| Calcium builds strong bones | Treats osteoporosis |
| Fiber maintains bowel regularity | Relieves chronic constipation |
| Supports a healthy immune system | Prevents colds and flu |
A useful test: if the sentence names a condition a doctor would diagnose, or implies the product fixes one, treat it as a disease claim.
The conditions that come with it
The FDA does not pre-approve structure/function claims, but a supplement that uses one has three obligations.
- Substantiation: The manufacturer must have substantiation that the claim is truthful and not misleading
- Disclaimer: The label must state that the FDA has not evaluated the claim, and that the product is not intended to diagnose, treat, cure or prevent any disease
- Notification: The manufacturer must send the FDA the text of the claim no later than 30 days after marketing the supplement with the claim
Supplements versus conventional foods
The rules differ if your product is a conventional food instead of a supplement.
- Scope: For conventional foods, these claims focus on effects from nutritive value. For supplements, they may also cover non-nutritive effects
- Notification: The FDA does not require conventional food manufacturers to notify it of structure/function claims
- Disclaimer: Not required for conventional foods
Watch the whole page
A carefully worded claim can be undone by what sits around it. As a cautious practice, review the product name, images and featured testimonials along with the description, and treat the items below as red flags to check.
- ❌ A product name that includes a disease or condition
- ❌ A featured review saying the product cured something
- ❌ "Supports joint health" beside a paragraph about arthritis
- ✅ Benefit statements that stay with normal body function, backed by evidence you hold
Advertising is also covered by the FTC, which expects health claims to be supported by competent and reliable scientific evidence. See supplement claims under the FDA and FTC and cosmetic versus drug claims for more.
Doing this at scale
ContentGuard scans your product descriptions and classifies each claim as safe, risky or prohibited against the rule profile you choose, such as US Dietary Supplement. It cites the governing FDA or FTC rule, scores each page, and proposes a rewrite you can apply in one click. It is a screening tool, not a substitute for legal review. See ContentGuard.