Serum TSH concentration

availability_state

machinery_impairment Imported condition classification; unverified.

cross_nutrient

Selenoenzyme D2 activates an iodine-containing hormone for feedback; knockout is a machinery experiment.

evidence_locator

Results: TSH Suppression Studies and Figure 9; pages 2140–2141.

evidence_spans

[{"source_document": "artifacts/iodine-metabolism-sources/11731615.txt", "locator": "Primary article Results, Figures 7 and 9; Methods: Assays for Serum T4, T3 and TSH, page 2146", "start_char": 20490, "end_char": 22790}]

experimental_model

Dio2-null mice and wild-type littermates, including hormone challenge after hypothyroidism

exposure

Male mice made hypothyroid for four weeks with methimazole/perchlorate; PTU inhibited D1. Subcutaneous T4 3 micrograms/100 g body weight or T3 1.2 micrograms/100 g; serum collected five hours later.

limitations

Pharmacologic hormone challenge after thyroid synthesis blockade and D1 inhibition; not a human dosing rule or dietary selenium-deficiency experiment.

nutrient_topic

Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine

organism

Mus musculus

plain_language

T3 bypassed the missing local T4-activation step in this feedback experiment.

primary_references

[i-met-11731615] Targeted disruption of the type 2 selenodeiodinase gene (DIO2) results in a phenotype of pituitary resistance to T4. (2001). https://pubmed.ncbi.nlm.nih.gov/11731615/ DOI: 10.1210/mend.15.12.0740

tissue_or_cell_type

Pituitary feedback and serum TSH

trigger_kind

machinery_impairment Imported condition classification; unverified.

Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 1025–1038

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Dio2-null mice and wild-type littermates, including hormone challenge after hypothyroidism · source_derived_draft · unverified_draft

### i-met-dio2-t4-feedback T4 suppressed serum TSH in hypothyroid wild-type mice but not Dio2-null mice; administered T3 suppressed TSH in both genotypes. Condition category: machinery_impairment nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: T3 bypassed the missing local T4-activation step in this feedback experiment. organism: Mus musculus tissue_or_cell_type: Pituitary feedback and serum TSH experimental_model: Dio2-null mice and wild-type littermates, including hormone challenge after hypothyroidism limitations: Pharmacologic hormone challenge after thyroid synthesis blockade and D1 inhibition; not a human dosing rule or dietary selenium-deficiency experiment. exposure: Male mice made hypothyroid for four weeks with methimazole/perchlorate; PTU inhibited D1. Subcutaneous T4 3 micrograms/100 g body weight or T3 1.2 micrograms/100 g; serum collected five hours later. cross_nutrient: Selenoenzyme D2 activates an iodine-containing hormone for feedback; knockout is a machinery experiment. evidence_locator: Results: TSH Suppression Studies and Figure 9; pages 2140–2141. evidence_spans: [{"source_document": "artifacts/iodine-metabolism-sources/11731615.txt", "locator": "Primary article Results, Figures 7 and 9; Methods: Assays for Serum T4, T3 and TSH, page 2146", "start_char": 20490, "end_char": 22790}] [i-met-11731615] Targeted disruption of the type 2 selenodeiodinase gene (DIO2) results in a phenotype of pituitary resistance to T4. (2001). https://pubmed.ncbi.nlm.nih.gov/11731615/ DOI: 10.1210/mend.15.12.0740

cross_nutrient

false

evidence_location

Primary indexed abstract.

experimental_model

Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults

exposure

Twelve groups received 0–2000 micrograms/day supplemental iodine. Mean reported dietary and salt iodine contributions were 105 ± 25 and 258 ± 101 micrograms/day.

limitations

Short study with small dose groups. Total background iodine differs among participants; the approximately 800 micrograms/day total at the 400-microgram supplement is the authors’ estimate, not a universal safe/unsafe threshold. Exact chemical formulation not verified from abstract. Baseline participants were euthyroid; increased TSH alone does not identify the molecular inhibition step.

nutrient_topic

Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine

organism

Homo sapiens

plain_language

More iodine raised TSH in this short dose-ranging trial.

primary_references

[iod-clin-sang2012] Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial. (2012). https://pubmed.ncbi.nlm.nih.gov/22205314/ DOI: 10.3945/ajcn.111.028001

tissue_or_cell_type

Serum thyroid indices, ultrasound and urinary iodine

Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 1454–1466

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults · source_derived_draft · unverified_draft

### iod-clin-excess-tsh All iodide-supplemented groups had significant increases in TSH and median urinary iodine relative to placebo after four weeks (P<0.05). Condition category: normal nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: More iodine raised TSH in this short dose-ranging trial. organism: Homo sapiens tissue_or_cell_type: Serum thyroid indices, ultrasound and urinary iodine experimental_model: Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults limitations: Short study with small dose groups. Total background iodine differs among participants; the approximately 800 micrograms/day total at the 400-microgram supplement is the authors’ estimate, not a universal safe/unsafe threshold. Exact chemical formulation not verified from abstract. Baseline participants were euthyroid; increased TSH alone does not identify the molecular inhibition step. exposure: Twelve groups received 0–2000 micrograms/day supplemental iodine. Mean reported dietary and salt iodine contributions were 105 ± 25 and 258 ± 101 micrograms/day. cross_nutrient: false evidence_location: Primary indexed abstract. [iod-clin-sang2012] Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial. (2012). https://pubmed.ncbi.nlm.nih.gov/22205314/ DOI: 10.3945/ajcn.111.028001

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Vitamin A/iodine -> thyroid feedback.

experimental_model

404 children; factorial trial.

limitations

TSH-beta transcriptional suppression is an explanation, not a directly measured step in these children.

nutrient_topic

Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A

organism

Homo sapiens

plain_language

Vitamin A status affected how strongly the thyroid was being stimulated.

primary_references

[va-zimmermann2007-iodine] Vitamin A supplementation in iodine-deficient African children decreases thyrotropin stimulation of the thyroid and reduces the goiter rate (2007). https://pubmed.ncbi.nlm.nih.gov/17921382/ DOI: 10.1093/ajcn/86.4.1040

tissue_or_cell_type

Pituitary-thyroid axis

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1578–1588

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 404 children; factorial trial. · source_derived_draft · unverified_draft

### va-iodine-context-lowers-tsh Vitamin A without iodine supplementation lowered TSH in the iodine-deficient study setting. Condition category: nutrient_deficiency nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Vitamin A status affected how strongly the thyroid was being stimulated. organism: Homo sapiens tissue_or_cell_type: Pituitary-thyroid axis experimental_model: 404 children; factorial trial. limitations: TSH-beta transcriptional suppression is an explanation, not a directly measured step in these children. cross_nutrient: Vitamin A/iodine -> thyroid feedback. [va-zimmermann2007-iodine] Vitamin A supplementation in iodine-deficient African children decreases thyrotropin stimulation of the thyroid and reduces the goiter rate (2007). https://pubmed.ncbi.nlm.nih.gov/17921382/ DOI: 10.1093/ajcn/86.4.1040

evidence_span

{"source_cache": "artifacts/inositol-research/24224112.fulltext.txt", "locator": "Exact primary full-text span; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b9b55ed122a2f26149680eb0f4bfab9ea981927754bcbb40305d4697c5d32412", "start_char": 7984, "end_char": 8184, "text_sha256": "34e1c5b3fe451ea1278c2adfb27f4977a40d100b82946252ecad03a7879592dc"}

experimental_model

Double-blind randomized combination trial

exposure

Myo-inositol plus selenomethionine versus selenomethionine

limitations

Small combination trial without a myo-inositol-only arm. A significant within-group change versus a nonsignificant change in the other arm is not by itself a significant between-group difference or nutrient synergy.

nutrient_topic

Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)

organism

Homo sapiens

plain_language

A thyroid blood marker improved in the combined-treatment group, but these comparisons do not establish a statistical interaction between nutrients.

primary_references

[ino-p24224112] Combined treatment with Myo-inositol and selenium ensures euthyroidism in subclinical hypothyroidism patients with autoimmune thyroiditis. (2013). https://pubmed.ncbi.nlm.nih.gov/24224112/ DOI: 10.1155/2013/424163

tissue_or_cell_type

Women with autoimmune subclinical hypothyroidism

Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 1419–1430

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Double-blind randomized combination trial · source_derived_draft · unverified_draft

### ino-thyroid-combination TSH fell from baseline in the myo-inositol-plus-selenomethionine arm, while no TSH change was reported in the selenomethionine-only arm; the reported TSH P value was a within-group comparison. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: A thyroid blood marker improved in the combined-treatment group, but these comparisons do not establish a statistical interaction between nutrients. organism: Homo sapiens tissue_or_cell_type: Women with autoimmune subclinical hypothyroidism experimental_model: Double-blind randomized combination trial limitations: Small combination trial without a myo-inositol-only arm. A significant within-group change versus a nonsignificant change in the other arm is not by itself a significant between-group difference or nutrient synergy. exposure: Myo-inositol plus selenomethionine versus selenomethionine evidence_span: {"source_cache": "artifacts/inositol-research/24224112.fulltext.txt", "locator": "Exact primary full-text span; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b9b55ed122a2f26149680eb0f4bfab9ea981927754bcbb40305d4697c5d32412", "start_char": 7984, "end_char": 8184, "text_sha256": "34e1c5b3fe451ea1278c2adfb27f4977a40d100b82946252ecad03a7879592dc"} [ino-p24224112] Combined treatment with Myo-inositol and selenium ensures euthyroidism in subclinical hypothyroidism patients with autoimmune thyroiditis. (2013). https://pubmed.ncbi.nlm.nih.gov/24224112/ DOI: 10.1155/2013/424163

cross_nutrient

false

evidence_location

Primary indexed abstract.

experimental_model

Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults

exposure

Twelve groups received 0–2000 micrograms/day supplemental iodine. Mean reported dietary and salt iodine contributions were 105 ± 25 and 258 ± 101 micrograms/day.

limitations

Short study with small dose groups. Total background iodine differs among participants; the approximately 800 micrograms/day total at the 400-microgram supplement is the authors’ estimate, not a universal safe/unsafe threshold. Exact chemical formulation not verified from abstract. These percentages are reported study-group findings, not an individual risk calculator. The authors estimated about 800 micrograms/day total intake in the 400-microgram supplement group; adding two overall mean background values is not a group-specific intake measurement.

nutrient_topic

Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine

organism

Homo sapiens

plain_language

Higher iodine exposure produced abnormal thyroid-function classifications in some participants.

primary_references

[iod-clin-sang2012] Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial. (2012). https://pubmed.ncbi.nlm.nih.gov/22205314/ DOI: 10.3945/ajcn.111.028001

tissue_or_cell_type

Serum thyroid indices, ultrasound and urinary iodine

Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 1468–1480

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults · source_derived_draft · unverified_draft

### iod-clin-excess-subclinical Subclinical hypothyroidism occurred in 5% of the 400-microgram/day supplement group and 15–47% of the 500–2000-microgram/day groups. Condition category: normal nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: Higher iodine exposure produced abnormal thyroid-function classifications in some participants. organism: Homo sapiens tissue_or_cell_type: Serum thyroid indices, ultrasound and urinary iodine experimental_model: Four-week randomized double-blind placebo-controlled dose trial in 256 euthyroid Chinese adults limitations: Short study with small dose groups. Total background iodine differs among participants; the approximately 800 micrograms/day total at the 400-microgram supplement is the authors’ estimate, not a universal safe/unsafe threshold. Exact chemical formulation not verified from abstract. These percentages are reported study-group findings, not an individual risk calculator. The authors estimated about 800 micrograms/day total intake in the 400-microgram supplement group; adding two overall mean background values is not a group-specific intake measurement. exposure: Twelve groups received 0–2000 micrograms/day supplemental iodine. Mean reported dietary and salt iodine contributions were 105 ± 25 and 258 ± 101 micrograms/day. cross_nutrient: false evidence_location: Primary indexed abstract. [iod-clin-sang2012] Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial. (2012). https://pubmed.ncbi.nlm.nih.gov/22205314/ DOI: 10.3945/ajcn.111.028001

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

false

evidence_location

Primary PDF Methods, trial profile, Results and Table2, pp.197–209.

experimental_model

Double-blind randomized trial in Morocco;241 mother–infant pairs enrolled, 239 randomized after two age exclusions

exposure

Term infants ≤ 8 weeks; indirect arm 121 pairs: mother 400 mg iodine as oral iodized poppyseed oil, infant placebo; direct arm 118 pairs: infant about 100 mg iodine from half a 200 mg oil capsule, mother placebo; follow-up 3, 6, 9 months.

limitations

Both arms received active iodine somewhere in the pair; there was no wholly untreated arm. Breastfeeding and baseline deficiency contextualize the result; measured iodine status is not a child cognitive outcome. Actual infant study dose was about 100 mg, not the 200 mg guideline discussed elsewhere in the paper. No serious adverse events were reported; this does not establish safety for other infant doses, preparations or settings.

nutrient_topic

Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine

organism

Homo sapiens

plain_language

A categorical thyroid outcome improved even though average hormone comparisons were not significant.

primary_references

[iod-clin-bouhouch2014] Direct iodine supplementation of infants versus supplementation of their breastfeeding mothers: a double-blind, randomised, placebo-controlled trial. (2014). https://pubmed.ncbi.nlm.nih.gov/24622750/ DOI: 10.1016/s2213-8587(13)70155-4

tissue_or_cell_type

Breast milk, infant urine and thyroid function

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 1566–1578

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Double-blind randomized trial in Morocco;241 mother–infant pairs enrolled, 239 randomized after two age exclusions · source_derived_draft · unverified_draft

### iod-clin-lactation-hypofunction Infant thyroid hypofunction classifications were less frequent with indirect maternal supplementation (P=0.023), although infant TSH and T4 concentrations did not differ significantly between groups over time (P=0.597 and 0.184). Condition category: nutrient_deficiency nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: A categorical thyroid outcome improved even though average hormone comparisons were not significant. organism: Homo sapiens tissue_or_cell_type: Breast milk, infant urine and thyroid function experimental_model: Double-blind randomized trial in Morocco;241 mother–infant pairs enrolled, 239 randomized after two age exclusions limitations: Both arms received active iodine somewhere in the pair; there was no wholly untreated arm. Breastfeeding and baseline deficiency contextualize the result; measured iodine status is not a child cognitive outcome. Actual infant study dose was about 100 mg, not the 200 mg guideline discussed elsewhere in the paper. No serious adverse events were reported; this does not establish safety for other infant doses, preparations or settings. exposure: Term infants ≤ 8 weeks; indirect arm 121 pairs: mother 400 mg iodine as oral iodized poppyseed oil, infant placebo; direct arm 118 pairs: infant about 100 mg iodine from half a 200 mg oil capsule, mother placebo; follow-up 3, 6, 9 months. cross_nutrient: false evidence_location: Primary PDF Methods, trial profile, Results and Table2, pp.197–209. [iod-clin-bouhouch2014] Direct iodine supplementation of infants versus supplementation of their breastfeeding mothers: a double-blind, randomised, placebo-controlled trial. (2014). https://pubmed.ncbi.nlm.nih.gov/24622750/ DOI: 10.1016/s2213-8587(13)70155-4

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

true

evidence_location

Primary indexed abstract.

experimental_model

Placebo-controlled selenium intervention in 52 schoolchildren from a region of severe iodine and selenium deficiency in northern Zaire

exposure

Selenium 50 micrograms/day as selenomethionine or placebo for two months; no concurrent iodine-repletion regimen reported in the abstract.

limitations

The abstract reports before/after changes in the selenium group; do not mistake these for adjusted between-group estimates. DIO1 restoration was a proposed explanation, not directly measured. Hormone changes do not themselves establish symptomatic deterioration or a universal order for supplement treatment.

nutrient_topic

Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine

organism

Homo sapiens

plain_language

The hormone pattern changed unevenly; T3 and TSH did not simply rise with selenium.

primary_references

[iod-clin-contempre1992] Effect of selenium supplementation on thyroid hormone metabolism in an iodine and selenium deficient population. (1992). https://pubmed.ncbi.nlm.nih.gov/1424183/ DOI: 10.1111/j.1365-2265.1992.tb02268.x

tissue_or_cell_type

Serum thyroid-hormone concentrations

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 1286–1298

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Placebo-controlled selenium intervention in 52 schoolchildren from a region of severe iodine and selenium deficiency in northern Zaire · source_derived_draft · unverified_draft

### iod-clin-selenium-rt3 Mean reverse T3 fell from 124 ± 115 to 90 ± 72 pmol/L after selenium treatment (P<0.05), while serum T3 and TSH did not change significantly. Condition category: nutrient_deficiency nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: The hormone pattern changed unevenly; T3 and TSH did not simply rise with selenium. organism: Homo sapiens tissue_or_cell_type: Serum thyroid-hormone concentrations experimental_model: Placebo-controlled selenium intervention in 52 schoolchildren from a region of severe iodine and selenium deficiency in northern Zaire limitations: The abstract reports before/after changes in the selenium group; do not mistake these for adjusted between-group estimates. DIO1 restoration was a proposed explanation, not directly measured. Hormone changes do not themselves establish symptomatic deterioration or a universal order for supplement treatment. exposure: Selenium 50 micrograms/day as selenomethionine or placebo for two months; no concurrent iodine-repletion regimen reported in the abstract. cross_nutrient: true evidence_location: Primary indexed abstract. [iod-clin-contempre1992] Effect of selenium supplementation on thyroid hormone metabolism in an iodine and selenium deficient population. (1992). https://pubmed.ncbi.nlm.nih.gov/1424183/ DOI: 10.1111/j.1365-2265.1992.tb02268.x