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

The library supports 8 wordings for vitamin C; the strongest is “Provides an antioxidant that helps protect cells against damage from free radicals” (strong, 6-2,000 mg a day). Avoid wording that names or implies a disease, a drug or a treatment, such as “Prevents, cures or shortens colds and flu”.

Also called: Ascorbic acid, L-ascorbic acid

Reviewed 15 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.

Strong evidenceWording 1

Claims Facts

“Provides an antioxidant that helps protect cells against damage from free radicals.”

Daily dose	6-2,000 mg a day
Support	Health Canada lists antioxidant wording, and the EU authorizes protection of cells from oxidative stress after EFSA review.
Dose details	Health Canada: 6-2,000 mg a day for adults 19 and older (6-1,800 mg at 14 to 18). EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). ODS upper limit: 2,000 mg a day for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Sources	Health Canada monograph: Multi-Vitamin/Mineral Supplements Commission Regulation (EU) No 432/2012, list of permitted health claims

Strong evidenceWording 2

Claims Facts

“Helps form collagen for healthy bones, cartilage, teeth and gums.”

Daily dose	6-2,000 mg a day
Support	Health Canada lists collagen formation for bones, cartilage, teeth and gums, and the EU authorizes normal collagen formation for the same tissues after EFSA review.
Dose details	Health Canada: 6-2,000 mg a day for adults 19 and older (6-1,800 mg at 14 to 18). EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). ODS upper limit: 2,000 mg a day for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Sources	Health Canada monograph: Multi-Vitamin/Mineral Supplements Commission Regulation (EU) No 432/2012, list of permitted health claims

Strong evidenceWording 3

Claims Facts

“Supports normal immune function.”

Daily dose	6-2,000 mg a day
Support	Listed by Health Canada and authorized in the EU after EFSA review.
Dose details	Health Canada: 6-2,000 mg a day for adults 19 and older (6-1,800 mg at 14 to 18). EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). ODS upper limit: 2,000 mg a day for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Sources	Health Canada monograph: Multi-Vitamin/Mineral Supplements Commission Regulation (EU) No 432/2012, list of permitted health claims

Strong evidenceWording 4

Claims Facts

“Supports normal function of the nervous system.”

Daily dose	6-2,000 mg a day
Support	Listed by Health Canada and authorized in the EU after EFSA review.
Dose details	Health Canada: 6-2,000 mg a day for adults 19 and older (6-1,800 mg at 14 to 18). EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). ODS upper limit: 2,000 mg a day for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Sources	Health Canada monograph: Multi-Vitamin/Mineral Supplements Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 5

Claims Facts

“Helps the body absorb iron.”

Daily dose	12-2,000 mg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). 2,000 mg a day is the ODS upper limit for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 6

Claims Facts

“Helps reduce tiredness and fatigue.”

Daily dose	12-2,000 mg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). 2,000 mg a day is the ODS upper limit for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 7

Claims Facts

“Plays a part in normal energy metabolism.”

Daily dose	12-2,000 mg a day
Support	Authorized in the EU after EFSA review; Health Canada lists only a role in the body’s ability to metabolize nutrients.
Dose details	EU: at least 12 mg, 15% of the 80 mg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). 2,000 mg a day is the ODS upper limit for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 8

Claims Facts

“Helps maintain normal immune function during and after intense physical exercise.”

Daily dose	200-2,000 mg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: the product must give 200 mg a day, and the consumer must be told the effect comes from 200 mg a day on top of the recommended daily intake. 2,000 mg a day is the ODS upper limit for adults.
Form	Ascorbic acid or a listed ascorbate, counted as vitamin C
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

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: Vitamin C

Wording to avoid	Reason
“Prevents, cures or shortens colds and flu”Names infectious diseases; the supported wording is normal immune function.	Disease
“Boosts immunity to fight infections”Implies an effect on infections; the supported wording is normal immune function.	Disease
“Fights or prevents cancer”Names a disease. FDA’s qualified claims on antioxidant vitamins and cancer come with disclaimers saying the evidence is limited or highly uncertain (see fda_health_claims).	Disease
“Heals wounds”Promises to heal damage to the body. Health Canada’s wound-healing use is a Canada only note.	Treatment

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

Check the claims on your own site. Free.

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