title: Thyroid hormone and obesity.
abstract: OBJECTIVE
  To review several of the most recent and most important clinical studies regarding the effects of thyroid treatments on weight change, associations between thyroid status and weight, and the effects of obesity and weight change on thyroid function.
  
  
  RESULTS
  Weight decreases following treatment for hypothyroidism. However, following levothyroxine treatment for overt hypothyroidism, weight loss appears to be modest and mediated primarily by loss of water weight rather than fat. There is conflicting evidence about the effects of thyroidectomy on weight. In large population studies, even among euthyroid individuals, serum thyroid-stimulating hormone is typically positively associated with body weight and BMI. Both serum thyroid-stimulating hormone and T3 are typically increased in obese compared with lean individuals, an effect likely mediated, at least in part, by leptin. Finally, there is no consistent evidence that thyroid hormone treatment induces weight loss in obese euthyroid individuals, but thyroid hormone analogues may eventually be useful for weight loss.
  
  
  CONCLUSIONS
  The interrelationships between body weight and thyroid status are complex.
authors.affiliation: Boston University School of Medicine, Boston, Massachusetts 02118, USA. elizabeth.pearce@bmc.org
authors.forename: Elizabeth N
authors.initials: EN
authors.lastname: Pearce
mesh_terms: D000273:Adipose Tissue; D015992:Body Mass Index; D001834:Body Water; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy / Q000378:metabolism*; D008297:Male; D009765:Obesity / Q000188:drug therapy / Q000378:metabolism*; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000378:metabolism* / Q000503:physiopathology; D013963:Thyroid Hormones / Q000008:administration & dosage*; D013965:Thyroidectomy / Q000009:adverse effects; D013974:Thyroxine / Q000008:administration & dosage* / Q000031:analogs & derivatives; D015431:Weight Loss
chemical_list: D013963:Thyroid Hormones; D013974:Thyroxine