The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women

<h3>Background</h3><p dir="ltr">The health benefits of soy are widely reported but there are queries on the effect of soy isoflavones on thyroid function and the underlying mechanism of action.</p><h3>Materials and Methods</h3><p dir="ltr"&g...

Full description

Saved in:
Bibliographic Details
Main Author: Thozhukat Sathyapalan (704787) (author)
Other Authors: Josef Köhrle (198859) (author), Eddy Rijntjes (83492) (author), Alan S. Rigby (7545887) (author), Soha R. Dargham (3613250) (author), Eric S. Kilpatrick (6684365) (author), Stephen L. Atkin (6684368) (author)
Published: 2018
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1864513525898018816
author Thozhukat Sathyapalan (704787)
author2 Josef Köhrle (198859)
Eddy Rijntjes (83492)
Alan S. Rigby (7545887)
Soha R. Dargham (3613250)
Eric S. Kilpatrick (6684365)
Stephen L. Atkin (6684368)
author2_role author
author
author
author
author
author
author_facet Thozhukat Sathyapalan (704787)
Josef Köhrle (198859)
Eddy Rijntjes (83492)
Alan S. Rigby (7545887)
Soha R. Dargham (3613250)
Eric S. Kilpatrick (6684365)
Stephen L. Atkin (6684368)
author_role author
dc.creator.none.fl_str_mv Thozhukat Sathyapalan (704787)
Josef Köhrle (198859)
Eddy Rijntjes (83492)
Alan S. Rigby (7545887)
Soha R. Dargham (3613250)
Eric S. Kilpatrick (6684365)
Stephen L. Atkin (6684368)
dc.date.none.fl_str_mv 2018-11-01T00:00:00Z
dc.identifier.none.fl_str_mv 10.3389/fendo.2018.00698
dc.relation.none.fl_str_mv https://figshare.com/articles/journal_contribution/The_Effect_of_High_Dose_Isoflavone_Supplementation_on_Serum_Reverse_T3_in_Euthyroid_Men_With_Type_2_Diabetes_and_Post-menopausal_Women/25331338
dc.rights.none.fl_str_mv CC BY 4.0
info:eu-repo/semantics/openAccess
dc.subject.none.fl_str_mv Biomedical and clinical sciences
Clinical sciences
soy
isoflavones
phytoestrogens
reverse tri-iodothyronine
tri-iodothyronine
thyroxine
TSH
dc.title.none.fl_str_mv The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
dc.type.none.fl_str_mv Text
Journal contribution
info:eu-repo/semantics/publishedVersion
text
contribution to journal
description <h3>Background</h3><p dir="ltr">The health benefits of soy are widely reported but there are queries on the effect of soy isoflavones on thyroid function and the underlying mechanism of action.</p><h3>Materials and Methods</h3><p dir="ltr"> We examined the effect of soy isoflavones on reverse tri-iodothyronine (or 3,3′,5′-tri-iodothyronine; rT<sub>3</sub>) in two studies comprising 400 patients: 200 men (study 1; 3 months) and 200 post-menopausal women (study 2; 6 months) who were randomized to consume 15 g soy protein with 66 mg of isoflavones (SPI) daily, or 15 g soy protein alone without isoflavones (SP) daily.</p><h3>Results</h3><p dir="ltr">SPI supplementation increased rT<sub>3</sub> serum concentration in both men 0.41 (0.12) vs. 0.45 (0.14) nmol/L and women 0.33 (0.12) vs. 0.37 (0.09) nmol/L at 3 months compared to SP that was not seen at 6 months. Thyroid stimulating hormone (TSH) serum concentrations increased while free thyroxine (fT<sub>4</sub>) concentrations decreased with 3 months of SPI compared to SP supplementation for both men and women. rT<sub>3</sub> correlated with TSH in both studies (<i>p</i> = 0.03) but not with either fT<sub>3</sub> or fT<sub>4</sub>. fT<sub>3</sub> levels did not differ between the SPI and SP preparations.</p><h3>Conclusion</h3><p dir="ltr">Soy isoflavones transiently increased rT3 levels within 3 months though reverted to baseline at 6 months. The mechanism for this would be either rT3 degrading deiodinase 1 and/or deiodinase 2 activities are transiently inhibited at 3 months, or inhibition of deiodinase 3, which generates rT3 from T4 is induced at 6 months. These changes were mirrored in the TSH concentrations, suggesting that short-term high dose isoflavone transiently impairs thyroid function in the first 3 months and may impact on general health during this period.</p><p dir="ltr"><b>ISRCTN Registry:</b> ISRCTN 90604927; ISRCTN34051237.</p><h2>Other Information</h2><p dir="ltr">Published in: Frontiers in Endocrinology<br>License: <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank">https://creativecommons.org/licenses/by/4.0/</a><br>See article on publisher's website: <a href="https://dx.doi.org/10.3389/fendo.2018.00698" target="_blank">https://dx.doi.org/10.3389/fendo.2018.00698</a></p>
eu_rights_str_mv openAccess
id Manara2_4ddbc103e5527348758cdc108e869717
identifier_str_mv 10.3389/fendo.2018.00698
network_acronym_str Manara2
network_name_str Manara2
oai_identifier_str oai:figshare.com:article/25331338
publishDate 2018
repository.mail.fl_str_mv
repository.name.fl_str_mv
repository_id_str
rights_invalid_str_mv CC BY 4.0
spelling The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal WomenThozhukat Sathyapalan (704787)Josef Köhrle (198859)Eddy Rijntjes (83492)Alan S. Rigby (7545887)Soha R. Dargham (3613250)Eric S. Kilpatrick (6684365)Stephen L. Atkin (6684368)Biomedical and clinical sciencesClinical sciencessoyisoflavonesphytoestrogensreverse tri-iodothyroninetri-iodothyroninethyroxineTSH<h3>Background</h3><p dir="ltr">The health benefits of soy are widely reported but there are queries on the effect of soy isoflavones on thyroid function and the underlying mechanism of action.</p><h3>Materials and Methods</h3><p dir="ltr"> We examined the effect of soy isoflavones on reverse tri-iodothyronine (or 3,3′,5′-tri-iodothyronine; rT<sub>3</sub>) in two studies comprising 400 patients: 200 men (study 1; 3 months) and 200 post-menopausal women (study 2; 6 months) who were randomized to consume 15 g soy protein with 66 mg of isoflavones (SPI) daily, or 15 g soy protein alone without isoflavones (SP) daily.</p><h3>Results</h3><p dir="ltr">SPI supplementation increased rT<sub>3</sub> serum concentration in both men 0.41 (0.12) vs. 0.45 (0.14) nmol/L and women 0.33 (0.12) vs. 0.37 (0.09) nmol/L at 3 months compared to SP that was not seen at 6 months. Thyroid stimulating hormone (TSH) serum concentrations increased while free thyroxine (fT<sub>4</sub>) concentrations decreased with 3 months of SPI compared to SP supplementation for both men and women. rT<sub>3</sub> correlated with TSH in both studies (<i>p</i> = 0.03) but not with either fT<sub>3</sub> or fT<sub>4</sub>. fT<sub>3</sub> levels did not differ between the SPI and SP preparations.</p><h3>Conclusion</h3><p dir="ltr">Soy isoflavones transiently increased rT3 levels within 3 months though reverted to baseline at 6 months. The mechanism for this would be either rT3 degrading deiodinase 1 and/or deiodinase 2 activities are transiently inhibited at 3 months, or inhibition of deiodinase 3, which generates rT3 from T4 is induced at 6 months. These changes were mirrored in the TSH concentrations, suggesting that short-term high dose isoflavone transiently impairs thyroid function in the first 3 months and may impact on general health during this period.</p><p dir="ltr"><b>ISRCTN Registry:</b> ISRCTN 90604927; ISRCTN34051237.</p><h2>Other Information</h2><p dir="ltr">Published in: Frontiers in Endocrinology<br>License: <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank">https://creativecommons.org/licenses/by/4.0/</a><br>See article on publisher's website: <a href="https://dx.doi.org/10.3389/fendo.2018.00698" target="_blank">https://dx.doi.org/10.3389/fendo.2018.00698</a></p>2018-11-01T00:00:00ZTextJournal contributioninfo:eu-repo/semantics/publishedVersiontextcontribution to journal10.3389/fendo.2018.00698https://figshare.com/articles/journal_contribution/The_Effect_of_High_Dose_Isoflavone_Supplementation_on_Serum_Reverse_T3_in_Euthyroid_Men_With_Type_2_Diabetes_and_Post-menopausal_Women/25331338CC BY 4.0info:eu-repo/semantics/openAccessoai:figshare.com:article/253313382018-11-01T00:00:00Z
spellingShingle The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
Thozhukat Sathyapalan (704787)
Biomedical and clinical sciences
Clinical sciences
soy
isoflavones
phytoestrogens
reverse tri-iodothyronine
tri-iodothyronine
thyroxine
TSH
status_str publishedVersion
title The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
title_full The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
title_fullStr The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
title_full_unstemmed The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
title_short The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
title_sort The Effect of High Dose Isoflavone Supplementation on Serum Reverse T3 in Euthyroid Men With Type 2 Diabetes and Post-menopausal Women
topic Biomedical and clinical sciences
Clinical sciences
soy
isoflavones
phytoestrogens
reverse tri-iodothyronine
tri-iodothyronine
thyroxine
TSH