title: Changes in lifestyle improve body composition, thyroid function, and structure in obese children.
abstract: BACKGROUND
  Alterations in thyroid function and structure have been reported in obesity. Function reverses to normal after weight loss, but nothing is known about structure.
  
  
  OBJECTIVE
  To evaluate the effect of weight loss on thyroid function and structure in obese children.
  
  
  METHODS
  The study was conducted in 72 overweight and obese children. Measurement of free T(3) (fT(3)), free T4 (fT(4)), TSH, antithyroid- antibodies and a thyroid ultrasound was performed at the beginning (phase 1) and after a period of 1.8±1.0 yr of lifestyle intervention (phase 2).
  
  
  RESULTS
  Height SD score (SDS), body mass index SDS, total fat mass did not change from phase 1 to phase 2. Percentage of fat free mass decreased significantly (p<0.05). Waist/height ratio decreased (0.6±0.1 vs 0.5±0.1; p<0.05) as well as waist/hip ratio (0.9±0.1 vs 0.8±0.1; p<0.05). In phase 1, TSH was 2.8±1.7 mU/l; in phase 2, it was 2.2±0.9 mU/l (p<0.05); 17.2% of children showed a TSH level above the normal range (3.6 mU/l) in phase 1, and 6.2% in phase 2 (p<0.05). fT(4) was 10.8±2.2 pg/ml in phase 1 and 10.7±1.9 pg/ml in phase 2. fT(3) was 4.4±1.3 pg/ml (phase 1) and 3.9±1.1 pg/ml (phase 2) (p<0.05). Thyroid volume was -0.5±0.8 SDS (phase 1) and -0.5±1 SDS (phase 2). A non-significant improvement in thyroid structure was observed.
  
  
  CONCLUSIONS
  In conclusion, healthier lifestyle improves body composition, thyroid function, and structure.
authors.affiliation: Department of Pediatrics, Regional Hospital of Bolzano, Bolzano, Italy. giorgio.radetti@asbz.it
authors.forename: G
authors.initials: G
authors.lastname: Radetti
authors.forename: S
authors.initials: S
authors.lastname: Longhi
authors.forename: M
authors.initials: M
authors.lastname: Baiocchi
authors.forename: W
authors.initials: W
authors.lastname: Cassar
authors.forename: F
authors.initials: F
authors.lastname: Buzi
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood; D001823:Body Composition; D002648:Child; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D009765:Obesity / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D050177:Overweight / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D015397:Program Evaluation; D013961:Thyroid Gland / Q000033:anatomy & histology* / Q000502:physiology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D016896:Treatment Outcome; D014284:Triiodothyronine / Q000097:blood; D061217:Weight Reduction Programs / Q000379:methods* / Q000458:organization & administration
chemical_list: D001323:Autoantibodies; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine