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

The library supports 5 wordings for iodine; the strongest is “Supports normal thyroid function” (strong, 22.5-800 µg a day). Avoid wording that names or implies a disease, a drug or a treatment, such as “Treats hypothyroidism, goiter or other thyroid disease”.

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

“Supports normal thyroid function.”

Daily dose	22.5-800 µg a day
Support	Listed by Health Canada and authorized in the EU after EFSA review.
Dose details	Adults 19 and older. Health Canada: 14-800 µg a day. EU: at least 22.5 µg, 15% of the 150 µg EU reference value (Regulation (EU) No 1169/2011, Annex XIII); its wording is normal production of thyroid hormones and normal thyroid function. ODS upper limit: 1,100 µg.
Form	Iodine from a salt on Health Canada’s list (such as potassium iodide), counted as iodine
Sources	Health Canada monograph: Multi-Vitamin/Mineral Supplements Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 2

Claims Facts

“Supports normal cognitive function.”

Daily dose	at least 22.5 µg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 22.5 µg, 15% of the 150 µg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). Health Canada does not list this use; its monograph allows at most 800 µg a day for adults. ODS upper limit: 1,100 µg.
Form	Iodine from a salt on Health Canada’s list (such as potassium iodide), counted as iodine
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 3

Claims Facts

“Supports normal energy-yielding metabolism.”

Daily dose	at least 22.5 µg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 22.5 µg, 15% of the 150 µg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). Health Canada does not list this use; its monograph allows at most 800 µg a day for adults. ODS upper limit: 1,100 µg.
Form	Iodine from a salt on Health Canada’s list (such as potassium iodide), counted as iodine
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 4

Claims Facts

“Supports normal function of the nervous system.”

Daily dose	at least 22.5 µg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 22.5 µg, 15% of the 150 µg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). Health Canada does not list this use; its monograph allows at most 800 µg a day for adults. ODS upper limit: 1,100 µg.
Form	Iodine from a salt on Health Canada’s list (such as potassium iodide), counted as iodine
Source	Commission Regulation (EU) No 432/2012, list of permitted health claims

Moderate evidenceWording 5

Claims Facts

“Helps maintain normal skin.”

Daily dose	at least 22.5 µg a day
Support	Authorized in the EU after EFSA review; Health Canada does not list it.
Dose details	EU: at least 22.5 µg, 15% of the 150 µg EU reference value (Regulation (EU) No 1169/2011, Annex XIII). Health Canada does not list this use; its monograph allows at most 800 µg a day for adults. ODS upper limit: 1,100 µg.
Form	Iodine from a salt on Health Canada’s list (such as potassium iodide), counted as iodine
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: Iodine

Wording to avoid	Reason
“Treats hypothyroidism, goiter or other thyroid disease”Names diseases.	Disease
“Fixes a slow or sluggish thyroid”Implies hypothyroidism, a disease.	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

Check the claims on your own site. Free.

Vera, Merchient’s AI employee, reads your site and emails you the riskiest line, why, a safer rewrite and how many more like it she found. Reply, and you get the free first report.

Get your free scan Book a 20-minute call

Or write to hello@merchient.com