What is a structure/function claim on a supplement?

A structure/function claim describes how a nutrient or dietary ingredient is intended to affect the normal structure or function of the human body. Examples include “calcium builds strong bones,” “fiber maintains bowel regularity,” and “supports the immune system.” On a dietary supplement, this kind of claim is not FDA preapproval of the claim or product.

Quick read: Treat a structure/function claim as a statement to investigate, not proof of a result. Find the ingredient tied to the words, check the amount per serving, and look for evidence on the same ingredient, form, amount, outcome, and population. The required FDA disclaimer means the claim was not evaluated by FDA before use; it does not verify effectiveness, safety, or legal compliance.

Understand what the claim describes

FDA says a structure/function claim may do either of these things:

describe the role of a nutrient or dietary ingredient intended to affect normal body structure or function; or
describe the documented mechanism by which the ingredient acts to maintain that structure or function.

FDA gives examples such as:

“calcium builds strong bones”;
“fiber maintains bowel regularity”; and
“antioxidants maintain cell integrity.”

The wording focuses on normal structure or function rather than diagnosing, mitigating, treating, curing, or preventing a disease. Phrases such as “supports,” “maintains,” and “promotes” often appear, but no single verb automatically determines the claim category. FDA says wording and context both matter.

A claim can also concern general well-being from consuming a dietary ingredient. These general-well-being claims follow the same key supplement-label requirements discussed below.

Separate structure/function, health, and nutrient claims

FDA recognizes several claim categories that answer different questions:

Claim type	What it describes	Example shape
Structure/function claim	An ingredient’s intended effect on normal body structure or function	“Calcium builds strong bones”
Health claim	A relationship between a food substance and reduced risk of a disease or health-related condition	“Adequate calcium may reduce the risk of osteoporosis”
Nutrient content claim	The amount or level of a nutrient in the product	“High calcium” or “low sodium”
Disease claim	A product’s intended effect on diagnosing, mitigating, treating, curing, or preventing disease	“Treats osteoporosis”

Health claims and qualified health claims have their own FDA authorization or enforcement-discretion pathways. Nutrient content claims must meet defined criteria when they characterize a nutrient as high, low, reduced, or similar.

A lawful structure/function claim is not a shortcut around those systems. It cannot explicitly or implicitly turn into a disease claim merely by using softer language.

Read the required FDA disclaimer accurately

A dietary supplement label carrying a structure/function claim, general-well-being claim, or certain nutrient-deficiency claims must include this standard disclaimer:

“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 disclaimer tells you that FDA did not evaluate the claim before it was used and that the supplement is not presented as a disease treatment. It does not mean:

FDA approved the claim;
FDA approved the supplement;
FDA verified the supporting studies;
the claim is effective for everyone;
the product has no safety risks or interactions; or
the rest of the marketing can contradict the disclaimer.

FDA says dietary supplements and their labeling generally are not approved before sale. The firm—not FDA—has the initial responsibility for ensuring the supplement and claim comply with the law.

Know what the manufacturer must do

For a dietary supplement structure/function claim, the company must have substantiation that the statement is truthful and not misleading. It must notify FDA with the claim text and other required information no later than 30 days after first marketing the supplement with the claim.

That is a notification, not an application for claim approval. FDA says the three claim types covered by this notification process are:

structure/function claims;
general-well-being claims; and
certain classical nutrient-deficiency disease claims that also disclose how common the deficiency is in the United States.

The claim must use the standard disclaimer prominently and cannot claim to diagnose, mitigate, treat, cure, or prevent a specific disease or class of diseases.

Seeing the disclaimer does not prove that the company submitted its notification on time or that the evidence is adequate. It identifies the regulatory framework the label is invoking.

Check the whole marketing context for disease meaning

A phrase can imply a disease claim without naming a disease directly. FDA and FTC both look beyond one sentence to the message created by the surrounding context.

Watch for combinations such as:

a product name that contains a disease name or a word such as “cure”;
images showing a diseased organ, medical procedure, prescription symbol, or before-and-after recovery;
references to characteristic signs or symptoms strongly associated with a disease;
a claim that the supplement replaces a drug or has fewer side effects than a treatment;
a claim that the supplement improves the effect of a named drug or therapy;
scientific-paper titles used to imply treatment of a disease; or
testimonials describing treatment, prevention, or cure.

FDA’s compliance guide explains that “supports the immune system” can describe normal function, while wording such as “supports the body’s ability to resist infection” focuses the claim on disease prevention. Context can change what reasonable readers understand.

FTC gives a similar example: “maintains joint health and mobility” can imply arthritis treatment when paired with a disease-suggestive product name and before-and-after images. Read the net message, not only the safest sentence on the page.

Do not let the disclaimer erase a contradictory claim

FTC says the supplement-label disclaimer does not cure deceptive advertising. A prominent disclaimer cannot cancel an explicit or implied disease claim elsewhere.

For example, an ad cannot claim that a supplement treats diabetes and then rely on “not intended to diagnose, treat, cure, or prevent any disease” to make the treatment claim acceptable. Those statements contradict each other.

The distinction also depends on where the claim appears. FDA generally leads on supplement labeling, while FTC generally leads on advertising. Websites, social posts, influencer content, packaging, testimonials, and images can all contribute to the marketing message. A compliant-looking bottle does not make every advertisement accurate.

Check the evidence against the exact claim

FDA requires the firm to substantiate that its structure/function claim is truthful and not misleading. FTC says health-related marketing generally needs competent and reliable scientific evidence.

Use these questions to inspect the support:

Which ingredient is supposed to produce the effect? A multi-ingredient product can make that hard to identify.
Is the studied ingredient the same form? A different extract, strain, salt, or preparation may not behave the same way.
Does the studied amount match the amount per serving? A study on a different amount does not automatically support the label.
Was the finished product studied, or only one ingredient? Other ingredients and combinations can change relevance.
Does the outcome match the wording? A laboratory marker is not automatically proof of a meaningful consumer result.
Does the population match the audience? Evidence from a narrow group may not support a claim for everyone.
What does the full body of evidence show? One favorable study should not hide stronger or conflicting results.

Testimonials and customer surveys are not substitutes for controlled evidence. “Clinically tested” also does not tell you whether a study found the claimed result, used the marketed product, or was designed well.

The third-party testing guide explains why a quality seal cannot establish that a health claim works.

Connect the words to the Supplement Facts panel

A claim on the front should lead back to the quantitative label.

Check:

the ingredient associated with the claim;
amount per serving;
how many capsules, gummies, scoops, or other units make one serving;
ingredient form or source;
proprietary blends that hide individual amounts;
other ingredients; and
warnings, directions, and company contact information.

A phrase such as “supports focus” does not tell you which ingredient is responsible or how much is present. If the ingredient amount is hidden inside a proprietary blend, it may be difficult to connect the formula with research.

The supplement-label guide provides a panel-by-panel reading order. The serving-size guide explains how to convert a declared amount to one capsule, scoop, packet, or container.

Distinguish supplement claims from conventional-food claims

Structure/function claims can also appear on conventional foods, but the special supplement notification and disclaimer rules do not apply in the same way.

FDA says conventional-food structure/function claims focus on effects derived from nutritive value. Conventional-food manufacturers do not have to notify FDA about these claims, and the supplement disclaimer is not required on conventional foods.

Do not infer that a conventional food is a supplement because it uses “supports” language. Check the product identity and the label system it actually uses.

Avoid common claim-reading mistakes

Keep these boundaries clear:

Structure/function does not mean FDA-approved. These supplement claims are not preapproved.
The disclaimer is not a quality seal. It describes a legal boundary; it does not verify evidence.
“Supports” is not automatically safe wording. Context can imply treatment or prevention.
Notification is not authorization. A firm reports the claim after marketing begins; FDA does not approve it through that notice.
Evidence must match the marketed claim. Ingredient, form, amount, outcome, population, and finished formula matter.
A disclaimer cannot contradict the ad. Disease claims do not disappear because small print says otherwise.
Testimonials do not prove causation. Individual experiences can be genuine without establishing a product effect.
Label and advertising oversight differ. FDA and FTC have related but distinct roles.

This guide explains U.S. supplement-claim categories and a way to read marketing language. It does not determine whether a supplement is effective, diagnose a condition, or recommend using a product instead of medical care.

Structure/function claim FAQ

What is an example of a structure/function claim?

FDA gives examples such as “calcium builds strong bones,” “fiber maintains bowel regularity,” and “antioxidants maintain cell integrity.” These describe intended effects on normal body structure or function rather than treatment or prevention of a disease.

Are structure/function claims approved by FDA?

No. FDA does not preapprove these dietary supplement claims. The company must have substantiation, use the required disclaimer, and notify FDA no later than 30 days after first marketing the supplement with the claim.

What does “This statement has not been evaluated by the FDA” mean?

It means FDA did not evaluate the structure/function or related claim before it was used. It does not mean FDA approved the supplement, verified the evidence, or determined that the product is effective or safe for everyone.

What is the difference between a structure/function claim and a health claim?

A structure/function claim describes an intended effect on normal body structure or function. A health claim describes a relationship between a food substance and reduced risk of a disease or health-related condition and follows a separate FDA pathway.

Can a supplement claim to treat a disease if it includes the FDA disclaimer?

No. A dietary supplement structure/function claim cannot explicitly or implicitly claim to diagnose, mitigate, treat, cure, or prevent disease. FTC also says the disclaimer cannot cure an otherwise deceptive disease-treatment advertisement.