World Thyroid Day2026 · Date · History
European Thyroid Association and sister thyroid associations
About World Thyroid Day
World Thyroid Day is marked on May 25 to support better understanding of thyroid health and thyroid-related conditions.
Thyroid patient organizations and professional societies including the European Thyroid Association contribute education and awareness across countries.
Why World Thyroid Day matters
The thyroid gland produces hormones important for bodily function, but symptoms and treatment vary widely between individuals and conditions.
Public awareness should steer people toward evidence-based clinical assessment rather than self-prescribing iodine, supplements or hormone medicines.
History of World Thyroid Day
Thyroid Federation International (TFI) describes its members deciding in September 2007 to create World Thyroid Day and choosing May 25; the first celebration was planned for 2008.
The European Thyroid Association identifies 2008 as the introduction year and says international sister associations have supported the day since 2010. TFI distinguishes its initiating discussions and awareness-week role from any claim that it formally operates one central worldwide event.
How the observance developed
This timeline uses documented milestones from reviewed sources. Missing stages are left out rather than guessed.
Thyroid Federation International members and European Thyroid Association collaborators
TFI identifies its 2007 members’ proposal; ETA confirms 2008 introduction.
First documented observance
TFI documents original first-year plan and ETA documents initial 2008 observance.
European Thyroid Association, sister thyroid associations and participating patient organizations
ETA 2026 May 25 announcement and TFI campaign history; no assertion of one central global organizing body.
What the evidence establishes
Confirmed institutional roles and milestones are shown first. Details that could not be established from the reviewed sources are listed separately below.
5 fields not established in reviewed sources
How to Observe World Thyroid Day
Share Thyroid Federation International or medical-association educational materials appropriate to a general audience.
Ask local professional health services for qualified information about testing and treatment rather than generalizing from online symptom lists.
Respect each person’s privacy; avoid claims that nutrition or a supplement will prevent or cure every thyroid disorder.
World Thyroid Day Facts
May 25 is the established annual World Thyroid Day date.
TFI members agreed on the observance in 2007, and the first edition was celebrated in 2008.
TFI says a request for UN inclusion was not accepted; the day must not be presented as a UN-created public holiday.
Topic and context
What this page does not assume
- Keep the source-defined country, community, organizer or institutional scope; do not silently broaden it.
- Do not treat the title alone as proof of government recognition or public-holiday status.
- Do not add a creator, founding story or origin claim unless the supporting evidence establishes it.
- Health Information Not Medical Advice.
Evidence & sources
Sources used across the guide are gathered here. Labels show how each source supports the page, and contextual references are kept separate from primary evidence.
European Thyroid Association — 2026 board statement and history (opens in a new tab)
European Thyroid Association — World Thyroid Day (opens in a new tab)
Organizer Dedicated Page
Thyroid Federation International — founding history, 2007 decision, 2008 first observance and UN-request limitation (opens in a new tab)
Understand it, compare it, then explore further
Start with the most common factual questions, then compare closely related observances and explore useful connections.
Frequently asked questions
When is World Thyroid Day?
25 May The documented recurrence rule is: 25 May.
Does World Thyroid Day fall on the same date every year?
Yes. It uses a fixed annual date unless stronger evidence changes the pattern.
Is World Thyroid Day an official public holiday?
The reviewed sources verify it within this scope: international thyroid-health awareness observance. That recognition does not by itself make it a statutory public holiday; the site only makes public-holiday claims when reliable evidence explicitly does so.
Who established or recognizes World Thyroid Day?
The documented basis is: European Thyroid Association and sister thyroid associations. Supporting evidence includes European Thyroid Association — World Thyroid Day. The site does not infer a separate creator or founder unless reviewed evidence establishes one.
Is World Thyroid Day international or country-specific?
The documented scope is international or global: international thyroid-health awareness observance. That does not mean every country treats the date as a public holiday or observes it in the same way.
How is this page verified?
The factual information is checked against reviewed sources, including the date pattern, scope and institutional history. This page was checked on 2026-10-09.
When is World Thyroid Day?
May 25 each year.
When did World Thyroid Day begin?
TFI describes a 2007 member decision and a first celebration in 2008; the European Thyroid Association confirms the 2008 introduction.
Is it a UN-designated international health day?
No. TFI reports that its historical attempt to obtain UN inclusion was not accepted.
Is World Thyroid Day the same as International Thyroid Awareness Week?
No. World Thyroid Day is May 25, while the wider awareness week includes additional activities and dates.
Other observances on May 25
These observances are also listed on May 25, 2027.
African Liberation Day (African Day)
The official Government of The Gambia holiday list names May 25 as African Liberation Day (African Day).
Día de la Revolución de Mayo
Argentina’s national government identifies May 25 as Día de la Revolución de Mayo y Primer Gobierno Patrio and treats it as an immovable national holiday.
Geek Pride Day
Spanish press coverage documents May 25 as Día del Orgullo Friki/Geek Pride Day and traces the organized Spanish observance to 2006.
Independence Day
Jordan’s Prime Ministry preserves the 25 May 1946 independence declaration, while the Foreign Ministry independently lists May 25 as Independence Day among current public holidays.
International Skin Pigmentation Day
Bella Aurora first-party pages document International Skin Pigmentation Day on 25 May 2021 and call the 2022 campaign the second year running, supporting a 2021 first edition; a later regis…
National Bath Bomb Day
National Day Archives records May 25 of each calendar year and identifies Desert Bath Company as the 2021 creator; current calendar coverage preserves the same date.