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Why the science on T3 and genomics is not settled

Nature Reviews Endocrinology (2025)Cite this article

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We thank Mary Saunders for sharing her story (Saunders, M. Liothyronine treatment for hypothyroidism — a patient’s view. Nat. Rev. Endocrinol. 21, 453–454 (2025))1 and raising awareness about the challenges faced by some patients with hypothyroidism. While we recognize and sympathize with her experiences, we disagree on two specific statements about the role of the British Thyroid Foundation (BTF) and the status of the science around triiodothyronine (T3) and genomics.

The BTF has been supporting people with thyroid disorders for almost 35 years. We know that too many individuals do not get the level of care, empathy and understanding they deserve. Their symptoms are sometimes misdiagnosed or dismissed as not being genuine. We provide patients, carers and the public with up-to-date, evidence-based information about thyroid disorders, facilitated by our partnership with the British Thyroid Association (BTA) and the British Association of Endocrine and Thyroid Surgeons (BAETS). We work closely with patients and carers to understand their priorities and feed these back to the relevant healthcare professionals. We are not funded by the BTA or BAETS, nor are we “the mouthpiece”1 for the BTA. We are, however, the voice of patients and families affected by all thyroid disorders, as illustrated by our Trustees’ broad range of backgrounds and interests.

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Authors and Affiliations

  1. Addenbrooke’s Hospital, Cambridge, UK

    Greta Lyons

  2. British Thyroid Foundation, Harrogate, UK

    Julia Priestley

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  1. Greta Lyons
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  2. Julia Priestley
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Correspondence to Julia Priestley.

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Competing interests

G.L. is a specialist thyroid research nurse at Addenbrooke’s Hospital in Cambridge, UK. She is also the Chair of Trustees for the British Thyroid Foundation. J.P. declares no competing interests.

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Lyons, G., Priestley, J. Why the science on T3 and genomics is not settled. Nat Rev Endocrinol (2025). https://doi.org/10.1038/s41574-025-01185-x

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