Research

Hormonal

Selenium deficiency impairs the thyroid's ability to handle high iodine loads, potentially causing damage, and selenium supplementation must follow iodine normalization to prevent hypothyroidism.

If you have both iodine and selenium deficiencies, fix iodine first. Adding selenium too early can worsen thyroid function.

GoodConditionalMEDIUM confidence
In regions of combined severe iodine and selenium deficiency, normalization of iodine supply is mandatory before initiation of selenium supplementation in order to prevent hypothyroidism.
Michael Zimmermann et al. · Thyroid · 2002

Why this rating

Based on animal models and specific human case reports/observations in Zaire.

Source

The Impact of Iron and Selenium Deficiencies on Iodine and Thyroid Metabolism: Biochemistry and Relevance to Public Health

Michael Zimmermann et al. · Thyroid · 2002

DOI 10.1089/105072502761016494

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DOI resolved against Crossref · corpus check 2026-06-10

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