Body Fatness and Markers of Thyroid Function among U.S. Men and Women
Open Access
- 12 April 2012
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 7 (4), e34979
- https://doi.org/10.1371/journal.pone.0034979
Abstract
We evaluated the association of central versus overall adiposity on levels of thyroid stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) among euthyroid subjects taken from a cross-sectional, representative sample of the adult non-institutionalized U.S. population. The National Health and Nutrition Examination Survey 2007–2008 included 1,623 men and 1,491 women who were 20 years and older, with no history of thyroid or liver disease, kidney failure, diabetes, or thyroid function-altering prescription medication use (based on self-report), and having TSH, fT3, and fT4 levels between 0.5–4.49 mIU/L, 2.5–3.9 pg/mL, and 0.6–1.6 ng/dL, respectively. Associations between body mass index (BMI) and waist circumference (measures of overall and central adiposity, respectively) and TSH, fT3, and fT4 levels were estimated using multivariable linear regression models stratified by sex and adjusted for age, race, smoking status, and alcohol intake. An increase in serum TSH levels was observed for every 1-quartile increase in BMI in euthyroid men (3.8% [95% CI 0.8%, 6.8%]) and euthyroid women (4.0% [95% CI 1.6%, 6.5%]). Similar, albeit slightly weaker, associations were observed with waist circumference. We also found increases in fT3 levels with every 1-quartile increase in BMI (1.0% in men and 1.3% in women) and waist circumference (1.2% in men and 1.2% in women). No associations were observed with fT4. Our results provide support that BMI and waist circumference are positively associated with levels of serum TSH and f T3 but not fT4 among euthyroid adults. Longitudinal studies are needed to define the temporality of these associations and their potential health implications.Keywords
This publication has 34 references indexed in Scilit:
- Iodine Status of the U.S. Population, National Health and Nutrition Examination Survey, 2005–2006 and 2007–2008Thyroid®, 2011
- Free T4 is negatively correlated with body mass index in euthyroid womenThe Korean Journal of Internal Medicine, 2008
- Relations of Thyroid Function to Body WeightCross-sectional and Longitudinal Observations in a Community-Based SampleArchives of Internal Medicine, 2008
- The Clinical Significance of Subclinical Thyroid DysfunctionEndocrine Reviews, 2007
- Influence of thyroid dysfunction on serum concentrations of adipocytokinesCytokine, 2007
- Obesity is associated with increased serum TSH level, independent of thyroid functionSwiss Medical Weekly, 2007
- Free triiodothyronine and thyroid stimulating hormone are directly associated with waist circumference, independently of insulin resistance, metabolic parameters and blood pressure in overweight and obese womenClinical Endocrinology, 2007
- Hyperthyrotropinemia in Obese Children Is Reversible after Weight Loss and Is Not Related to LipidsJournal of Clinical Endocrinology & Metabolism, 2006
- Lack of association between serum TSH or free T4 and body mass index in euthyroid subjectsClinical Endocrinology, 2006
- High Circulating Thyrotropin Levels in Obese Women Are Reduced after Body Weight Loss Induced by Caloric RestrictionJournal of Clinical Endocrinology & Metabolism, 2005