What can you say about caffeine in your ads and on your site?

The library supports 2 wordings for caffeine; the strongest is “Temporarily helps promote alertness and wakefulness, and helps mental performance” (moderate, 100-1,000 mg a day). Avoid wording that names or implies a disease, a drug or a treatment, such as “A diuretic or water pill”.

Reviewed 14 October 2026

Not legal advice. This guide shows the wording that published evidence supports at a daily dose, from the sources linked below; it is not a ruling on any claim. Your own product, its form and dose, and your own evidence still need to match the wording you use.

Supported wordings

What you can say.

Moderate evidenceWording 1

Claims Facts

“Temporarily helps promote alertness and wakefulness, and helps mental performance.”

Daily dose	100-1,000 mg a day
Support	Health Canada lists it; FDA’s 2000 rule accepts alertness wording tied to occasional fatigue or drowsiness.
Dose details	Adults 18 and older: 100-200 mg per dose, at most 1,000 mg a day (energy shots 400 mg). Above 200 mg a day, wait 3-4 hours between doses.
Form	Caffeine
Source	Health Canada monograph: Caffeine

Moderate evidenceWording 2

Claims Facts

“Temporarily helps reduce fatigue and supports endurance and physical performance.”

Daily dose	100-1,000 mg a day
Support	Health Canada lists it, and ODS says caffeine might improve endurance, strength and power in athletes.
Dose details	As above. ODS: studies used about 2-6 mg per kg of body weight before exercise.
Form	Caffeine
Sources	Health Canada monograph: Caffeine NIH ODS fact sheet: Dietary Supplements for Exercise and Athletic Performance (health professional)

How strong the evidence is

Strong evidence: At least two listed sources support it independently at a comparable dose and form, and none disagrees.
Moderate evidence: One listed source supports it as an evidence-based use at that dose, and no listed source disagrees.
Limited evidence: The only support is traditional use, the sources disagree, or the source itself calls the evidence weak.

Wordings to avoid

What to leave out.

Claims Facts

Ingredient: Caffeine

Wording to avoid	Reason
“A diuretic or water pill”FDA’s 2000 rule (page 1026) lists ‘diuretic’ among class names that imply treating disease.	Drug
“Treats ADHD or narcolepsy”Names diseases.	Disease

Disease: names or implies a disease. Drug: names a drug or presents the product as one. Treatment: promises to treat, cure or prevent a condition.

Sources

Where this comes from.

All ingredient guides

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