Can I say it?
Can I say “prevents cancer” in a supplement ad?
Usually no. 6 rules fired across 3 sample sentences, and the checker's own text explains why.
The short answer
Usually no. The checker blocks the bare phrase in this setting. The first rule it hits is CG-DIS-003. Its reason: Claiming to prevent a disease or condition is a disease claim.
Source the rule cites: 21 CFR 101.93(g); FDCA 201(g)(1); FTC Health Products Compliance Guidance
Checked as an ad promoting a supplement or wellness product. Context changes the result. The same samples hit these blocking rules: 4 in a drug or device ad, 5 in a supplement ad, 3 in a clinical service ad.
A clear result is not an all-clear. The checker flags wording for review and does not know your evidence, your state or your platform's review. Read the limitations.
Sample wording, run through the checker
These are sentences written to contain the phrase, not real claims. Each ran through the real engine and the shipped rule-set when this site was built.
This daily blend prevents cancer.
- BlockingCG-DIS-003Disease claims. Matched: “prevents”
- BlockingCG-RFA-001Disease claims. Matched: “prevents cancer”
- BlockingCG-TRE-001Disease claims. Matched: “prevents cancer”
- Warning
CG-PLT-013Platform policy. Matched: “prevents cancer”
Our superfood powder helps prevent heart disease.
- BlockingCG-DIS-003Disease claims. Matched: “prevent”
- BlockingCG-DIS-010Disease claims. Matched: “helps prevent heart disease”
- BlockingCG-DIS-019Disease claims. Matched: “prevent heart disease”
- BlockingCG-RFA-001Disease claims. Matched: “helps prevent heart disease”
- BlockingCG-TRE-001Disease claims. Matched: “prevent heart disease”
- Warning
CG-PLT-013Platform policy. Matched: “prevent heart disease”
Prevents cancer and keeps your cells young.
- BlockingCG-DIS-003Disease claims. Matched: “Prevents”
- BlockingCG-RFA-001Disease claims. Matched: “Prevents cancer”
- BlockingCG-TRE-001Disease claims. Matched: “Prevents cancer”
- Warning
CG-PLT-013Platform policy. Matched: “Prevents cancer”
What to say instead
This version came back with no rule fired:
This blend is a daily supplement made with fruit and vegetable extracts. Ask your doctor about screening that fits your age and history.
What the rules themselves suggest:
- CG-DIS-003 Say "supports" a healthy lifestyle, or cite the specific guidance (for example a screening recommendation) instead of promising prevention.
- CG-DIS-010 Describe what the product contains or what the service involves, and leave the disease out. For a service, say who delivers care and that individual results vary.
- CG-DIS-019 Remove disease slowing, prevention and recovery claims. Describe a supplement by its nutrients only, and a stem cell service only as an investigational study.
The rules behind this answer
Reason, source and citation for each rule that fired, in the checker's own words. Blocking rules come first.
CG-DIS-003 · Blocks approval · Citation checked against stored text
Claiming to prevent a disease or condition is a disease claim.
Source: 21 CFR 101.93(g); FDCA 201(g)(1); FTC Health Products Compliance Guidance
Safer wording: Say "supports" a healthy lifestyle, or cite the specific guidance (for example a screening recommendation) instead of promising prevention.
21 CFR 101.93(g) · Needs counsel review
CG-DIS-010 · Blocks approval · Citation checked against stored text
Saying a product or service helps, improves or relieves a named disease or condition is a disease claim. For a product it makes the product an unapproved drug, and for a service it needs support.
Source: 21 CFR 101.93(g); FDCA 201(g)(1); FTC Act section 5; FTC Health Products Compliance Guidance
Safer wording: Describe what the product contains or what the service involves, and leave the disease out. For a service, say who delivers care and that individual results vary.
21 CFR 101.93(g) · Needs counsel review
CG-DIS-019 · Blocks approval · Citation checked against stored text
Claims to slow, stop or prevent a serious disease, or to restore function after spinal cord injury, are disease claims that need drug approval and evidence.
Source: FDCA 201(g)(1); 21 CFR 101.93(g); FDA consumer alerts on stem cell and dietary supplement disease claims; FTC Act section 5
Safer wording: Remove disease slowing, prevention and recovery claims. Describe a supplement by its nutrients only, and a stem cell service only as an investigational study.
21 CFR 101.93(g) · Needs counsel review
CG-RFA-001 · Blocks approval · Citation checked against stored text
Saying a product cures, treats, prevents, relieves or fights a named disease or condition makes it an unapproved drug claim, and the FDA cites this wording in warning letters.
Source: FDCA 201(g)(1); 21 CFR 101.93(g); FTC Health Products Compliance Guidance
Safer wording: Remove the disease claim. Describe only a lawful structure or function benefit and keep the disclaimer.
21 CFR 101.93(g) · Needs counsel review
CG-TRE-001 · Blocks approval · Citation checked against stored text
Saying a product kills tumors, reverses dementia, replaces sunscreen, controls blood sugar, or treats autism or other named diseases is an unapproved disease claim that supplements, devices and clinics cannot make without FDA clearance and substantiation.
Source: FDCA section 201(g) and 201(h); DSHEA 21 USC 343(r)(6) and 21 CFR 101.93(g) (disease claims on supplements); FTC Act section 5; FTC Health Products Compliance Guidance
Safer wording: Remove any statement that the product treats, cures, prevents, reverses or protects against a named disease. Describe only what an approved label or competent scientific evidence supports.
21 CFR 101.93(g) · Needs counsel review
CG-PLT-013 · Warns · Citation checked against stored text
Pinterest does not allow claims regarding the prevention or cure of disease, and Google does not allow non-approved products marketed as safe or effective for preventing, curing or treating a particular disease. Meta bars claims to cure, heal or eliminate incurable diseases (diabetes, herpes, thyroid conditions, psoriasis, cancer, autism, Alzheimer's, Parkinson's, HIV and others), even from health professionals. Reddit, Amazon, Outbrain, Nextdoor, Apple and Taboola bar implying that a product or supplement diagnoses, prevents or cures disease.
Source: Pinterest Advertising Guidelines (healthcare products and services); Google Ads Healthcare and medicines policy (unapproved substances); Meta Advertising Standards, Unrealistic outcomes; Meta Advertising Standards, Health and wellness; Reddit Ads Healthcare Products and Services policy; Amazon Ads Claims and substantiation policy; Outbrain Advertising Guidelines; Nextdoor Ads Policy; Apple Advertising Services policies; Taboola Health Supplement Advertising Guidelines
Safer wording: Say what the service does ("screening", "education", "treatment plans reviewed by a clinician") and leave out prevent, cure and reverse.
Meta Advertising Standards, Unrealistic outcomes, Meta Advertising Standards, Health and wellness, Taboola Health Supplement Advertising Guidelines, Outbrain Advertising Guidelines, Nextdoor Ads Policy, Apple Advertising Services policies, Reddit Ads Healthcare Products and Services policy, Amazon Ads Claims and substantiation policy, Google Ads Healthcare and medicines policy, Pinterest Advertising Guidelines
Background: Disease claim in the glossary.
Questions
Which rule covers prevention claims?
Rule CG-DIS-003. It cites 21 CFR 101.93(g). The rule's reason: Claiming to prevent a disease or condition is a disease claim.
What should I write instead?
The rule's own suggestion for rule CG-DIS-003: Say "supports" a healthy lifestyle, or cite the specific guidance (for example a screening recommendation) instead of promising prevention.
Does the answer change for a drug, a supplement or a service?
Context changes the result. The same samples hit these blocking rules: 4 in a drug or device ad, 5 in a supplement ad, 3 in a clinical service ad. Pick the type that matches what you promote when you run the checker.
Next step
Check your own wording
Paste your copy into the free checker. Every flag names its rule and its source.