Longitudinal changes in anthropometric and thyroid hormone homeostasis parameters during the 12-month weight-loss intervention. During the weight-loss intervention (A and B), a significant decrease in serum T3 was observed (C). A trend toward a reduction in thyrotropin (TSH) and free T4 (fT4) was also observed (D and E). No significant difference was observed in the reverse T3 (rT3) serum concentration throughout the study. Repeated measures analysis of variance (ANOVA), data are reported as mean±SEM. Number of observations: time 0=47, 1.5=47, 3=47, 6=42, 9=34, 12=31.