[Changes in various indices of thyroid function in obese adults during diet therapy]

Modifications in thyroid function caused by changes in diet have been reported in the literature though the results are often conflicting. The present study was conducted on 48 obese adults divided into two groups: the first over 60% and the second under 60% above their ideal weight. A control group of healthy subjects of normal weight and comparable age was also studied. The observation lasted 9 weeks during which a low calorie diet providing about 1250 kCal was administered. Mean basal levels of FT3, TT3, FT4 and TSH revealed no significant differences between the obese subjects and the control group. Mean TT4 was significantly higher in the obese and mean T3U significantly lower. During low calorie diet treatment the obese subjects produced no significant variations in the above parameters, apart from a significant increase in T3U. The study revealed no evidence of the low T3 syndrome that has long been reported in the literature.