97 377

Cited 0 times in

Effect of iodine restriction on short-term changes in thyroid function in patients with subclinical hypothyroidism

 Obin Kwon  ;  Dong Yeob Shin  ;  Eun Jig Lee 
 Journal of Nutrition and Health, Vol.55(2) : 250-262, 2022-04 
Journal Title
Journal of Nutrition and Health
Issue Date
subclinical hypothyroidism ; iodine ; thyroid gland
Elevated iodine intake is related to a higher prevalence of subclinical hypothyroidism (SCH). We investigated the short-term effect of dietary iodine restriction on thyroid function in patients with SCH with high iodine intakes.

The iodine levels in 64 SCH patients with serum TSH levels from 4.0 to 10.0 mIU/L and normal serum fT4 levels (n = 64) were assessed using 24-hour urine iodine test results and iodine intake levels calculated using a semi-quantitative food frequency questionnaire. Dietary iodine restriction was not recommended for patients with an iodine intake in the normal range (group A, n = 13), but seaweed restriction was recommended for patients with high iodine intakes (group B, n = 33). Thyroid functions and iodine levels were rechecked after three months. Another eighteen patients were prescribed thyroid hormone replacement therapy according to clinical criteria.

Median baseline iodine intake for the 64 patients was 290.61 μg/day, and median 24-hour urine iodine was 33.65 μmol/g of creatinine. The major source of dietary iodine was seaweed, which accounted for 72.2% of median baseline intake. Urine iodine and calculated iodine intake levels were positively correlated with serum TSH levels (p < 0.001 and p = 0.027, respectively), and calculated iodine intakes were significantly correlated with urine iodine levels (p = 0.001). In group B, iodine restriction significantly decreased urine iodine (p = 0.042) and TSH levels (p = 0.004), and conversion to euthyroid status was achieved in 16 of the 33 patients (48.5%).

Iodine intake and urine iodine levels are correlated with thyroid function in SCH patients, and dietary iodine restriction can aid functional thyroid recovery in patients with elevated iodine intakes.
Files in This Item:
T9992022816.pdf Download
Appears in Collections:
1. College of Medicine (의과대학) > Dept. of Internal Medicine (내과학교실) > 1. Journal Papers
Yonsei Authors
Shin, Dong Yeob(신동엽) ORCID logo https://orcid.org/0000-0003-1048-7978
Lee, Eun Jig(이은직) ORCID logo https://orcid.org/0000-0002-9876-8370
사서에게 알리기


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.